The Role of Physical Techniques on the Preparation of Photoanodes for Dye Sensitized Solar Cells

Review ArticleThe Role of Physical Techniques on the Preparation ofPhotoanodes for Dye Sensitized Solar Cells

Shideh Ahmadi1 Nilofar Asim2 M A Alghoul2 F Y Hammadi2 Kasra Saeedfar34

N A Ludin2 Saleem H Zaidi2 and K Sopian2

1 NOVITAS School of Electrical and Electronic Engineering Nanyang Technological University Singapore 6397982 Solar Energy Research Institute Universiti Kebangsaan Malaysia 43600 Bangi Selangor Malaysia3 School of Chemical Science amp Food Technology Faculty of Science and Technology Universiti Kebangsaan Malaysia43600 Bangi Selangor Malaysia

4Department of Chemistry Faculty of Science K N Toosi University of Technology Tehran 15875-4416 Iran

Correspondence should be addressed to Nilofar Asim asimnilofargmailcom and M A Alghoul dralghoulgmailcom

Received 14 August 2013 Revised 3 December 2013 Accepted 17 December 2013 Published 9 February 2014

Academic Editor Mahmoud M El-Nahass

Copyright copy 2014 Shideh Ahmadi et alThis is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Dye sensitized solar cells (DSSCs) have attracted numerous research especially in the context of enhancing their efficiency anddurability due to the low-cost and environmentally friendly nature of photovoltaic (PV) technology The materials in DSSCs arevital towards the realization of these goals since many of the important components are influenced by their respective preparationand deposition methods This review aims to detail the research and development aspects of the different physical methods withthe purpose of evaluating their prospects and corresponding limitations The diversity of consideration and criteria includes thinfilm applications material characteristics and process technology that need to be taken into account when selecting a specificdeposition method Choosing a deposition method is not as simple as it seems and is rendered quite complicated due to variousfactors Usually a researcher will evaluate techniques based on factors such as the different preparations and deposition technologywith materialsrsquo and substratesrsquo type specified applications costs and efficiencies

1 Introduction

Dye sensitized solar cells (DSSCs) in the form of novelphotovoltaic (PV) technology have widely huge potential forlow-cost and environmentally friendly solar cells comparedto their more traditional counterparts DSSCs are favoreddue to properties such as low weight flexibility transparencyvaried colors and superior performance in darker conditionsand have attracted considerable private sector investmentand government funding DSSC is considered as a promisingresearch topic due to the dependence of its power conversionefficiency on its materials However the materials [1] aloneare not enough to guarantee a stable efficient and low-cost dye sensitized solar cell [2ndash4] as its properties areintertwined with the preparation and deposition methodIt has been prepared via various deposition technologiesand these technologies are being intensely researched and

developed due to their unique advantages over others Thepurpose of this review highlights the different preparationsand deposition methods that have been utilized in DSSCapplications in order to emphasize their advantages anddisadvantages which will allow a researcher to select andoptimize a given method Moreover other parameters suchas sensitization and curing procedure play a significantrole in DSSCrsquos performance which must be taken intoaccount as well [5 6] There are two major categories inthe preparation and deposition methods including chemicaland physical methods We analyzed the chemical methodsin our previous paper [7] and this review will attempt todiscuss the physical applied methods in the preparationof DSSC Meanwhile the combination of both physicaland chemical reactions is being considered in the prepara-tion of DSSCs however this review is limited to physicalpreparations

Hindawi Publishing CorporationInternational Journal of PhotoenergyVolume 2014 Article ID 198734 19 pageshttpdxdoiorg1011552014198734

2 International Journal of Photoenergy

2 Physical Methods

Physical methods utilize physical phenomenon to prepareand deposit the materials Physical methods are furthercategorized according to their medium or precursors suchas gas or liquid We tried to categorize these methods byconsidering this concept although it does overlap from timeto time

21 Liquid Phase Precursors

211 Spin Coating Uniform thin films on flat substratesare deposited via the spin coating method which encom-passes products such as thin and ultrathin polymer filmsProcedures on spin coating include deposition spinupspinoff and evaporation (Figure 1) The overloaded solutionis deposited onto the substrate rotated at high speeds andfinally the solution coats the substrate via centrifugal forceThe desired thickness is obtained by continuous rotationThe solvent being volatile simultaneously evaporates Thefilmrsquos thickness is dependent on the solutionrsquos concentrationsolvent and spin speeds [8] The thin film is deposited by thehigh angular spin speedThe thickness of the films is less than10 nm which is useful in microfabrication and photolithog-raphy which requires the thickness of the photoresist to becirca 1 micrometer The film thickness is explained as follows[9]

ℎ = (1 minus120588119860

1205881198600

) sdot (3120578 sdot 119898

212058811986001205962)

(13)

(1)

where ℎ is thickness 120588119860is density of volatile liquid 120578 is

solution viscosity m is evaporation rate and 120596 is angularspeed For the experimental results ℎ = 119860120596minus119861 can be usedwhere119860 and119861 are constant parameters and119861 = 04 and 07 inmost casesThe desired thickness uniformfilm simple setupand low power consumption are some of the advantages ofthis method However its dependence of the substratersquos sizeof the spin coating process the lack of material sufficiencyhigh cost and its requirement for a flat substrate are some ofits known disadvantages [10] As can be seen in Table 1 thelist of materials could be used via the spin coating method inDSSC application

212 Dip Coating Dip coating results in a uniform thin filmof liquid deposition upon the substrate for small slabs andcylinders (Figure 2)The thickness of the film depends on theviscous force capillary (surface tension) force and gravityThe flow conditions of the liquid bath and gas overheadplay an important role in both thicknesses and uniformitiesThicker films resulted fromusing volatile solutes and combin-ing rapid sufficient drying via basic liquid flow The growththeoretical prediction and control of the process representsome of the challenges faced when utilizing this method Ifthe withdrawal speed is chosen in a way that the sheer ratesremain with the Newtonian regime the thickness deposition

Air flow

Radial liquid

Liquid film

Evaporation

Angular velocity

Radial liquid

Disk

flowflow

Figure 1 Spin coating procedure [11]

can be calculated by the Landau-Levich equation as follows[14]

ℎ = 094 sdot(120578 sdot V)23

12057416

LV (120588 sdot 119892)12 (2)

where h is coating thickness 120578 is viscosity V is dragging speed120574LV is liquid-vapor surface tension 120588 is density and 119892 is thegravity constant

The dip coating process is divided into five steps [15] (1)Immersion the substrate is immersed in the coating materialsolution at a consistent speed for a moment and (2) startupthe substrate is subsequently pulled up which precipitates theformation of a thin layer to formon the substrate Pullingup isperformed at a steady speed to eliminate any potential jitters(3) Deposition the thickness of the coating is controlled bythe pull speed as a thicker coating will form if the pull (with-drawal) speed is increased If a thinner layer is required then(4) drainage the excess liquid is drained and (5) evaporationany remaining solution on the coating is evaporated usingvolatile solvents such as alcohols This step is continuouslyrepeated The dip coating method is rather common whilethe spin coating method that was previously discussed ismore suitable for industrial purposes [16] The dip coatingmethod is used in DSSC applications such as Poly(N-vinyl-2-pyrrolidone)-capped platinum nanoclusters deposited onindium tin oxide glass (efficiency 284) [17] and meso-porousTiO

2films deposited on an F-doped tin oxidewith dye

(ruthenium complex bis-tetrabutylammoniumcis-dithiocya-nato-N1198731015840-bis-221015840-bipyridine-4-carboxylic acid 41015840-carbox-ylate ruthenium(II)) (efficiency 1080) [18]

213 Doctor Blade Printing (Knife to Edge) Roll to RollCeramic capacitors are the first recorded tape-castingmachines that were made by Glen Howatt [19] and this mar-velous invention is soon followed by the doctor blade or tapecastingmethodThemultilayer ceramic capacitors (MLCCs)low temperature cofired ceramics (LTCCs) lithium batteriesfuel cells oxygen separators and thermistors are some of thedevices that are manufactured by the tape casting methodThe application of thismethod vis-a-vis thin films is relativelyrecent which found its niche in nanotechnological advances

International Journal of Photoenergy 3

Table 1 List of materials was prepared via spin coating method for fabrication DSSC using some research results

Materials Efficiency120578 () Reference

Poly-3-phenylhydrazone thiophene (PPHT)ZnOPPHTDyeZnO 055 [64]PEDOTPSS film on FTO glass substrate 637 [65]ZnO nanowires 520 [66]Pt electrodes 718 [67]714-Bis[2-[tris(1-methylethyl)silyl]ethynyl]dibenzo[bdef ] chrysene (TIPS-DBC) layers on SWNTFTO mdash [68]MWCNT on FTO 494 [69]TiO2 nanoparticlesnanofibers bilayer film 475 [70]Nanocarbon composite with hierarchical porous structure 650 [71]Camphorsulfonic acid doped polyaniline (PANICSA) film 267 [72]Mesoporous TiO2 692 [73]Al2O3 and SiO2 nanoparticles on ZnO nanowire and nanoparticles 240 [74 75]PEDOTPSS (transparent thin films) mdash [76]TiO2NiO composite particles 327 [77]Thin film of ZnO on FTO (2Ml) 670 [78]ZnO compact film 776 [79]TiO2 film mdash [80]A polystyrene (PS) film of microporous or island-like structure 458 [81]GraphenePEDOT-PSS 450 [82]Thin films of poly(34-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOTPSS) 034 [83]Carbon-modified TiO2 electrode 560 [84]TiO2PEDOT 093 [85]SnO2 colloidal suspension (18 nm) mdash [86]Oleic acid graphite (OLA-G) films on FTO glass 077 [87]Spiro-OMeTAD (221015840771015840-tetrakis-(NN-di-p-methoxyphenylamine)-991015840-spirobifluorene) 302 [88]

Texture analyzer

Substrate

Solution

(a) (b)

(c)

Figure 2 Scheme of dip coating process (a) immersion (b) wetting and (c) withdrawal [12]


(a)

Solution deposition

Colloidal solution

Glass substrate

Solution spreading

Blade

Film drying1

of NCs

2 3

(b)

Figure 3 (a) A photograph of doctor blading (ErichsenCoatmaster 509MC-I) [11] and (b) First step the colloidal solution is deposited ontoglass substrate second step the blade spreads the solution over the substrate third step the obtained film is dried [13]

in ceramic body armor optical films medical films used asdrug delivery systems and microporous membranes

The well-defined thickness of films fabricated using thedoctor blade technique is detailed in Figure 3 This methodaptly named tape casting knife coating or knife-over-edgecoating due to transfer to reel-to reel coating (R2R) is alsoviable to be used to make films for polymer solar cells [20]The stages of this technique are summarized as themovementof a substrate at a constant speed under a blade with a specificheight and contact angle The function of this blade is tospread the paste onto the surface homogeneously and get afixed thick filmWe can also conduct the process by placing afixed amount of paste over the substrate to be deposited andthen unrollis using a glass rod is moved on the spacer onboth sides to determine the thickness of the film

This method is economical and it minimizes the lossof particles by around 5 compared to its spin coatingcounterpart As a result of this only a small amount ofstartingmaterials is sufficient for this method [11]The coatedthickness is around 10ndash500120583m using a sharp blade at a fixeddistance from the substratersquos surface The wet thickness ofthe film depends on the surface tension and the viscosityof the coating solution In practical terms this technique isanalogous to spin coating due to the enhanced initial lossof coating solution and the extended time that is requiredto determine the best coating parameters However it isconsidered as one of the most straightforward and low-costprocess for semi-conductor paste deposition and one of thesimplest printing methods available for modern electronics

This method is suitable for mass production of elec-troceramic thick films as it requires less starting materialscompared to the spin coating method Despite its benefitsthere are some areas where it is lacking such as its slowevaporation or its tendency to aggregate or crystallize athigh solutionpaste concentration The large effective areaof the photovoltaic devices is based upon the compatibilitybetween the accepters and donors For example the bestcombination between fullerene as an acceptor and polymer(paraphenylenevinylene PPV) as a donor material is viablefor the doctor blade method without any loss of efficiency[21] This process could be performed manually in thelaboratory (Table 2) The researchers have built simple andquick samples of nanostructure semiconductor films and thismethod also allows science hobbyist to construct homemadesolar cells

214 Screen Printing The screen printing process is two-dimensional print layer patterning devised in the 20th cen-tury which was determined to have numerous industrialapplications First the porous printing plate is fabricatedusing a woven mesh of synthetic fabric threads or metalwire which is duly mixed with stencil as a masking materialThe process is detailed in Figure 4 The woven mesh isattached to a rigid aluminum or steel framework which has arectangular plane in a majority of the applications Howeverthe cylinder screen is also considered to be attached andsealed at both ends The semirigid planar surface createstension in the opposite direction of the mesh similar to


Table 2 The summarized materials are used by doctor baldingmethod for DSSC application


Blends of polymer and fullerene mdash [21]Porous carbonSnO2TiO2nanocomposite films 615 [89]

Sn doped ZnO nanostructures 182 [90]ZnO photoelectrodes 107 [91]ITO-PEN 424 [92]ZnO porous film 464 [93]TiO2 layer 810 [94]Carbon counter electrode (CE) 646 [95]Porous carbon counter electrodes 610 [96]TiO2 film was coated on aTi-isopropoxide-treatedstainless steel-based substrate

830 [97]

Cauliflower-like TiO2 rough spheres 736 [98]Porous ZnO photoelectrode 450 [99]Mesoporous TiO2 film 580 [100]FTO glass 910 [25]ZnO and TiO2 160 [101]Mesoporous TiO2 electrodes 050 [102]Pure anatase TiO2 nanocrystallites 565 [103]

TiO2 porous film

310 (glasssubstrate)490 (plasticsubstrate)

[104]

TiO2 on FTO glass 518 [105]

TiO2 photoanodes FTO glass 721 (front side)485 (back side) [106]

the tensions generated via the interaction between syntheticpolyester monofilaments or stainless steel This stretchedprinting screen achieves three discrete purposes (1) the fluidcoatingmeters under pressure (2) providing a surface for theshearing of the coating material viscous columns to transferto the substrate and (3) providing support for the imagingelements (the stencil) This method eliminates any loss of thecoating solution and produces a large wet thick film with ahigh viscosity

The screen printing method uses thick film printingproducing films that are around 10ndash15 microns Exampleof application of this method includes the DSSC electrodewith TiO

2as thick film deposited on a conductive glass

(FTOITO) This method is widespread in the electronicindustries to manufacturing DSSC in producing miniatureand robust electronic circuits in a cost-effective mannermassive and automated well-defined and with highly repro-ducible structures First the thick film screen printing ink orpaste is pressed onto the substrate by a mechanical squeegeetransferring the patterns [22] This method consists of a sol-vent (organic or inorganic salt) and a binder (TiO

2particles)

The role of the solvent provides an ink homogeneousmixturefor printing purposes The screen includes woven mesh of

stainless steel nylon or polyester mounted under tensionon a metal frame During printing the substrate is held at adistance from one side of the screen and the ink is depositedon the screen from the opposite side while a squeegeetraverses the screen under pressure Second the solvent willbe dried at 120∘Cwhich automatically guarantees the stabilityof the printed films and substrates The nonvolatile portionof the solvent evaporates under high temperature The mostpopular screen printable ink recipe contains ethanol for itssolvent terpineol for its dispersant ethyl cellulose for itsthickener and Triton X-100 for its surfactant [23] The watersolvent causes cracks to form on the film so organic solventsare used The long stability and superior morphology ofTiO2are important in dye adsorption which utilize terpineol

component and ethyl cellulose respectively The loadingnanoparticles on screening print are important because theyaffect the TiO

2structure although they reduce the efficiency

of DSSC if the dispersion is incomplete The low currentoutput and the decline in the efficiency of the solar cell aredue to the agglomeration of nanoparticles The thickness ofthe coated film is superior compared to the other methodssuch as offset lithography gravure flexography xerographyor ink-jet printing caused by the flow of coating materialbeing under pressure into and through this mesh or matrixvia coating on the substrate The high efficiency for DSSCis around 91 for porous TiO

2[24] and carbon black [25]

The ZnO nanoparticle shows an efficiency of 150 [26]whereas ZnO nanoparticles with two indoline dyes codedD149 and D205 observe higher efficiencies at 495 (D149)and 534 (D205) respectively [27] The ITO-PEN [28] andPt deposited on ITOpolyethylene naphthalate (ITOPEN)[29] have efficiencies of 541 and 720 respectively

215 Electrohydrodynamic Deposition (Electrospray Deposi-tion ESD) The liquid-phase process is a new method forfabricating thin films that are thinner than 10 120583m in MEMS(Microelectromechanical Systems) and NEMS (Nanoelec-tromechanical Systems) (Figure 5) The electrospray formsdroplets from the sample solution such as nanoparticles andthese droplets will be deposited on various substrates Theuniform solid film is formed by evaporating or heating thesolvent on the surface via sintering The thin films could beformed by a precursor compound which decomposes at hightemperatures or converts to another substance via chemicalreactions with other compounds that are simultaneouslysprayed or delivered during its gaseous phase [30] Thismethod could be used in physical and chemical reactions thatare taken into account in the physical aspect in this reviewThe metal nitrates or acetates dissolve in water methanoland ethanol and these mixtures are electrosprayed as pre-cursors for a metal-oxide layer production The advantageof this method is the usage of the less soluble materials[31] the ability to control charge droplet the lack of solventevaporation effects and the ability to form multilayered thinfilms The significant advantage of ESD is the multilayeredthin film growth being superior compared to spin coatingdip coating and screen printing since the bottom organiclayer solvent during the top layer growth cannot be avoided


MovementOpen area filled

Screen with

Ink

Squeegee

Printed ink

Frame

with ink

emulsion

Substrate

Figure 4 Schematic of screen printing [11]

HV

Particle suspension

Capillary

Substrate

Electrospray

(a)

HV

Particle precursor

Capillary

Substrate

Electrospray

Heating element

(b)

Figure 5 Schematic of electrospray deposition (a) from solution and (b) from precursor [30]

[32] The nanocrystalline TiO2electrodes [33] porous TiO

2

films [34] and terpyridine-coordinated dye [33] had theefficiencies of 597 510 and 248 respectively Thespray dye molecules onto TiO

2surfaces used this method

to develop molecular dye sensitized solar cells [31] Highconductivity (electrical resistivity of 2 times 10minus4Ω cm) and hightransmission of 78 in the visible range were observed in Tinoxide films [35]

3 Gas Phase Precursors

31 Physical Vapor Deposition (PVD) Thin film depositionvia PVD is regarded as a vacuum coating technology and isclassified into two techniques evaporation and sputteringThe material could be coated in an energetic and entropicenvironment since the particles will escape from the surfaceThe solid layer that is formed on the surface is due to thecooling of the particles once they lose their energy whenimmobilizedThe particles are capable ofmoving in a straightpath because the system is kept in vacuum and the filmsare coated by physical means that are commonly directionalrather than conformal in nature Examples of PVD method

prepared nanostructures in DSSCs are mesoporous TiO2

nanocolumnar films [36] (3mm-linear efficiency (240)3mmndash500 nm efficiency (220) 3mmndash100 nm efficiency(230) 5mmndash500 nm efficiency (250) and 6 120583m refer-ence P25 electrode efficiency (210)) ZnO nanostructuresdeposited on glass ITO substrate (efficiencies (010ndash050)for nanowires nanowire sheets branched Au and branchedZn [37]) TiO

2(nanotubes) deposition enhance dye loading

to up to 4720 and changing the efficiency to 628 forDSSC [38] and TiO

2electrodes deposited at different angles

(500 nm thickness efficiency (060ndash104) with modi-fied angle (60∘ndash85∘) and 3 120583m thickness efficiency (278)[39])

311 Evaporation Generally thin films are deposited byevaporation The source material is evaporated in a vacuumwhich allows the vapor particles to travel directly to thesubstrate as a target and condense into a solid state

Thermal Evaporation Thermal evaporation is a simple andeconomical method in fabricating thick films and microfilms(Figure 6) The source materials are melted or sublimatedvia electrical heating converting it into a gaseous phase


Table 3 Thermal evaporation method used for DSSC application

Materials Efficiency120578 ()

Reference

ZnO nanocombs onto FTO substrate 068 [107]

ZnOSb fiber on FTO mdash [108]ZnO with different thickness of NiO thinfilms 1-09 [109]

Arrays of ZnO nanowires 034ndash085 [110]

Mesoporous TiO2 mdash [111]

ZnO films onto FTO 156 [112]

ZnO nanofibers 088 [113]

Ag nanowires 270 [114]

Pt thin film on FTO 270 [115]

Vaporized material

Substrate

Deposition of thin film

Source material

Evaporator

Vacuum chamber

Heater

Figure 6 Schematic of thermal evaporation [40]

The vapor particles will then achieve a certain velocity in thechamber and will attempt to condense on the substrate Thesubstrates are located close to the source materials The highvacuum condition in the vacuum chamber will act to preventthe particles from scattering and minimize the residual gasimpurities The temperature is kept between 1000sim2000∘CThere are some disadvantages including poor adhesionbecause of low affinity with substrate surface and the need touse an adhesive layer due to evaporated temperature metaland low melting point materials are suitable and refractorymaterials and multicomponent alloys cannot be used con-tamination problems and poor step coverage (rendering pat-ternmaking impossible)Thefilm coatedwithout contamina-tion is made bymaterials that have amuch higher vapor pres-sure than the heating element The temperature and vaporpressure affect high deposition rates (up to 100 120583mmin)Surface damage is low because the vapor particle energy is

Substrate

Radiation heating

Crystal thickness monitor

Electron gun High vacuum chamber

Evaporant

Water cooled crucible containing materials

Figure 7 Schematic of electron-beam evaporation process [41]

around 10sim100meV The applications of DSSC are listed inTable 3

ElectronBeamEvaporation (EBE)Electron beamevaporationused high-speed electrons to bombard the source materialsDuring this process (Figure 7) the kinetic energy will be con-verted into thermal energy which increases the temperatureof the source An electron gun creates the electron beamThemagnetic field bends at an angle of 270∘ and the electronpath bombards the position The crucible acts as an anodeand is cooled by cooling water to prevent contaminationConsequently a pure thin film is formed Quite a numberof materials could be formed using this method such asdielectric oxide refractory metals and metal oxide (Table 3)This method allows the easy control of the melting materialswhich makes its deposition rate easily controlled as well(1 nmmin to 1 120583mmin) using multiple guns and sourcesThese advantages enhance the uniform thickness and createa multilayer deposition by changing the crucible and makingmultiple target film possible The surface however couldeasily be damaged by the decomposition or ionization ofthe target However the enormous electrical energy and X-ray that is consumed in this method put it at a distinctdisadvantage The EBE used in DSSC application is shown inTable 4

312 Sputtering The sputtering method was discovered in1852 as a means to monitor metals deposit at the cathodesof a cold cathode glow discharge This method was usedto coat mirror fabrics and phonograph wax masters Weanalyzed two kinds of sputtering including DC magnetronsputtering and radio frequency (RF) magnetron sputter-ing DC magnetron sputtering could increase depositionrates with minimal damage to the substrate while the RFmagnetron sputtering plays an important role in allowingdirect deposition of insulators The high quality depositionmaterials such as metal alloy and simple organic compoundcoatings were deposited using the sputtering method which


Table 4 List ofmaterials by using EBEmethod inDSSC application


Ti electrode coated on TiO2 layer 251 [116]TiO2 films 400 [117]TiO2 between the conductive transparentelectrode and the porous TiO2-basedphotoelectrode

701 [118]

Composite electrolyte (mixture ofheteropoly acids (HPA) and polyethyleneoxide (PEO))

340 [119]

TiO2 film 664 [120]Porous films of titanium oxide 410 [121]Nanoporous films (TiO2-6120583m) 610 [122]Nanocolumnar titanium oxide films(4 120583m) mdash [123]

Hollow atom dynamicsAuger decay and

X-ray emission

Sputtered atomsions

Hollow atom

Electrons

Incoming ionq+

Figure 8 Schematic of the processes that follow ion impact duringsputtering [42]

precipitates the preference of this method over other PVDmethods such as EBE and thermal evaporation (Table 5)Sputtering is considered a momentum transfer procedureAs the particles collide with a surface the procedure isdependent upon the incident particle energy the incidenceangle the surface atoms binding energy and the collidingparticles mass (Figure 8) The ions are regarded as theincident particles in sputtering which are accelerated by anapplied electrical potentialThey will be reflected or absorbedby the surface when the kinetic energy is less than 5 eV Thesurface will be damaged as the kinetic energy is higher thanthe surface atom binding energy when the atoms are placedinto new lattice positions

Sputtering occurs from the surface when the kineticenergy is above a certain threshold (10 to 30 eV) The sput-tered atoms and ions deposit the thin film onto the substrateA low-pressure process of the glow discharge type will usuallycause energetic ion bombardment The basic diode processis revealed in Figure 9 The vacuum chamber (argon 10ndash3 to10ndash1 torr) is supplied with a cathode as its target the coatingmaterial source and an anode as substrate for coatingDuringthe sputtering process the heat generated in the target isconnected to a water-cooled metal (copper) backing platewith a solder or conductive epoxy which cools the targetAn electrical potential is applied between the cathode andanode Grounded shields avoid discharges from forming in

Substrates

Target

Crookrsquosdark space

Glowdischarge

Figure 9 Schematic of a diode sputtering assembly [43]

Plasma region

Gas in

Vacu

um ch

ambe

r

High vacuum pump

Low vacuum pump

Sample holder

Power supply

Sample

MagnetronTarget

DC RF

(minus)

(+)

Gas in

Figure 10 Graphic of DC and RF sputtering [44]

undesirable areasThe sputter yield is dependent on the targetmaterial for example silver has high yield The deposition oflarge amounts of materials including compounds and mix-tures the inducement of better step coverage and uniformityand good adhesion with low substrate temperature are someof the advantages of this process but the risk of substratedamage due to ionic bombardment is omnipresent The listof materials used in DSSC application is shown in Table 4

DC Magnetron Sputtering DC magnetron sputtering is oneof the simpler and older sputter depositions methods It ismade up of two parallel electrodes 4ndash8 cm apart a cathode(target) and an anode (substrate) (Figure 10)The typical DC


Table 5 DSSC application by using sputtering method


ITO-PEN 810 [94]TiO2 nanowiresnanoparticles hybrid membrane 250ndash270 [124]ZnO nanostructured films gt458 [125]Nanofibrous ZnO layers 170 [126]ZnO compact layer 781 [127]Pt counter electrodes on micropatterned ITO substrates 536 [128]TiO2 blocking-layer coated CdS-sensitized 052 [129]PAMAM-like dendrons on SWCNT mdash [130]TiO2 microspheres with tunable sizes 678 [131]Pt-counter electrode (Pt-CE) 754 [132]Pt layer 511 [133]Carbon films 500 [134]Thin Pt electrode on transparent conductive oxide (TCO) substrate 600 [135]Composite poly(33-diethyl-34-dihydro-2H-thieno-[34-b][14]-dioxepine) and platinum (PProDOT-Et2Pt) film 668 [136]Ultra-thin Pt films on indium tin oxide (ITO) substrates 790 [137]ITO-x-SWCNT and ITO-x-SWCNT-N3 electrodes mdash [138]TiO2 nanoparticles with natural dye extracted from pomegranate leaves and mulberry fruits 055ndash072 [139]ZnO films of polyethylene glycol (PEG) 183 [140]PtTi bilayers 437 [141]CdS-sensitized TiO2 photoelectrode 104 [142]Different TiO2 passivating layers 285 [143]ZnO nanorod 032 [144]Ti doped ITiO films 380 [145]FTOnano-TiO2 440 [146]FTO glass 1118 [147]ITO-PEN film coated Pt layer 524 [148]Carbon electrode 389 [149]Polymerized poly(34-ethylenedioxythiophene) on conductive glass 450 [150]

potential that is applied is 1000ndash3000V the vacuum pump is10minus3 Pa and pressures are about 0075 to 012 torr Ions will beaccelerated in the plasma to the cathode then the target willbe bombarded and the sputtering energy is transferred fromthe target to the substratersquos surface This method should beused for conductive materials and is unsuitable for dielectricmaterial targets (Table 6) The good adhesion very lowlevels of contamination film properties control of pressurebias and temperature are some of the advantages of DCsputtering whereas some of its significant disadvantagesinclude plasma electrons bombarding the substrate andproducing heat high working gas pressure low depositionrate and targets being limited to electrical conductors Theperformance of this system can be improved by cathodesystems

Radio Frequency (RF)Magnetron Sputtering Insulatingmate-rials are suitable as materials in RF sputtering which areinduced by a positive charge on the target surface (Table 7)The negative bias voltage is produced on the target when

the AC potential with high frequency is applied mostlydue to the mobility difference between electrons and ionsThe positive ions bombard the target leading to sputtering(Figure 10) The deposition rate of RF sputtering mirrorsDC sputtering where the target will be positive for a shorttime when the mass electron approaches the mass of ionsTherefore the negative bias instigated sputtering on aninsulating target Practical applications utilized a frequencyof around 1356MHz and for industrial purposes utilizeda radio frequency designed by the Federal CommunicationsCommission RF sputtering deposits insulators with the sameequipment and at lower pressures (5 to 15 times 10minus3 torr)as well as conductors and semiconductors The blockageof the RF radiation by electromagnetic shielding is oneof the major disadvantages of RF sputtering Additionallyresonant RF network requires complex equipment such asthe power supplies and matching networks Overall RFsputtering demonstrates lower deposition rates compared toDC sputtering but its damage to a substrate is significantlylower than that of its DC counterpart


Table 6 The list of materials used via DC magnetron sputtering inDSSC application


ZnO film 182 [151]Pt metal grid 403 [152]Compact TiO2 deposited ontofluorine-doped tin oxide (FTO) 612 [153]

PtTiN thin film on PEN substrate 196 [154]TiO2 nanotube arrays 438 [155]Nickel oxide (NiOx) mdash [156]TiO2NiO electrodes 416 [157]TiO2 nanorod arrays 478 [158]Anatase TiO2 thin films mdash [159]Al-doped ZnO (AZO) films 061 [160]Thin TiO2 (anatase) films mdash [161]TiO2 films on SnO2F coated glasssubstrates 078 [162]

Al2O3-coated TiO2 electrode 591 [163]

Table 7 Materials in DSSC by RF magnetron sputtering methods


Reference

Aluminum-doped zinc oxide (AZO) thinfilms on glass substrates 291ndash413 [164]

Porous TiO2 films on FTO electrode 460 [165]

Compact ZnO interlayer 400 [166]

TiO2 covered FTO electrode mdash [167]

ZnOAl thin film 210 [168]Titanium-doped indium-tin-oxide(TiITO) and indium-tin-oxide (ITO) 375 [169]

Indium tin oxide (ITO) mdash [170]Aluminum oxynitride (AlOxNy) films onpolyethylene naphthalate (PEN)substrates

500 [171]

Triple-layered ITOATOTiO2 629 [172]

Pt counter electrode 360 [173]

Columnar-structured rutile TiO2 film 240 [174]

313 Pulsed Laser Deposition (PLD) The thin film depo-sition method used high power laser beams (108Wcmminus2)as a means of evaporation in ultra high vacuum chambersor gases such as oxygen (Figure 11) The laser is capableof evaporating the target source of heat or inducing photodissociation Then the materials will be converted to plasmaatomsmolecules and chunks and are duly deposited onto thesubstrate The film will not be damaged due to the absenceof the accumulating of electric charge The energy beam isregarded as a laser beam which does not scatter for longdistanceThe target source decreases the contamination to thelowest level This method is uncommon in the industry due

to lasers being rather expensiveThe advantage of thismethodis its alacrity and simplicity that it maintains stoichiometrythat it is crystalline its well-defined final structures itshigh complexity and mixtures materials its good adhesionand its compatibility with oxygen and other reactive gasesAll these properties could be controlled by laser intensitysubstrate temperature buffer gas pressure and incidentangle of the coating plume Particulates composition andthickness being dependent on the deposition are some ofthe disadvantages of this process Despite these considerableadvantages PLD is regarded as being too slow for industrialapplications due to three main factors such as the plasmaforwarding directly to the substrate being nonuniformdepositing in a relatively small area (sim1 cm2) and requiringnovel materials for the purpose of the optimization of depo-sition parameters The novel PLD method called GlancingAngle Pulsed Laser Deposition (GAPLD) [49] is used toprepare porous nanostructure thin filmsThis process has thestrength ability to control the shape of nanostructure suchas porous nanocolumnar film nanorod arrays with differentshapes nanospring arrays and multilayer nanostructuresIn this method the substrate is placed above the vaporsource at an oblique angle The composite TiO

2electrodes

show an efficiency of 380 [45] whereas the indium-tinoxide nanowires on glass have an efficiency of 015 [50]The optical properties of ITO and TiO

2single and double

layer thin films developed the functional materials for DSSCapplications [51] and the large surface area is imperative vis-a-vis dye-sensitized solar cells (DSSCs) applications [52]

314 Cathodic Arc Deposition (Arc-PVD) The arc-PVD isone of the ion beam deposition using electrical arc whichproduces the blasts ions from the cathode (Figure 12) Thehigh power density produced by the arc has a high levelof ionization (30ndash100) multiply charged ions neutral par-ticles clusters and macroparticles (droplets) The reactivegas is used throughout the evaporation procedure anddissociation ionization and excitation could occur duringthe interactionwith the ion flux which results in a compoundfilm being deposited Metallic ceramic and composite filmscould be prepared with this method The advantage of thisprocess is its compatibility with industry good adhesionof the product stoichiometry compounds low temperaturemultilayer coating compact film uniform film and lowvoltage The inability to coat complex geometries and theutilization of liquid droplets and metal macroparticles aresome of the disadvantages of this method [53] Arc-PVDmethod is one the methods for fabrication DSSC such asITOCrDLC (n-type)Pt (efficiency of 330) [54] TiO

2-

nanotube array (efficiency of 188) [55] and nanocrystallinetitania films (efficiency of 090) [56]

315Thermal Spraying (NoHighVacuum) Thermal sprayingis one of the coating methods that applies heat by electrical(plasma or arc) and chemical (combustion flame) means tomelt the materials with high temperature and spray particlesat high speeds on the surface (Figure 13) The liquid materialwill almost immediately form a film Thermal spraying


Outletaerosol filter

Homogenizer

UV transparentwindow

Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas

Excimer laser(248nm)

TiO2 nanoparticle suspension

Figure 11 Schematic of pulsed laser deposition [45]

Pumpingsystem

Specimen

Trigger

Holder

Trigger

Arc source Arc source

Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply

Figure 12 Graphic of arc-PVD [46]

included plasma spraying detonation spraying wire arcspraying flame spraying velocity oxy-fuel coating spraying(HVOF) warm spraying and cold spraying The thicknessof the deposited films usually ranges from 20120583m to severalmm which is indicative of a high deposition rate in alarge area relative to other chemical and physical vapordeposition methods Quite a number of materials are viablefor this process such as metals alloys ceramics plasticsand composites This process is considered rather efficient

in the context of DSSCs comparable to the doctor bladingmethod [57] The wide range of materials and substratesdrying process occurring in the spraying step the formationof the film at low temperatures and its rather quick pro-cessing method are some of the advantages of this methodMeanwhile some of its disadvantages are the difficulty incontrolling the thickness and its relatively low adhesion ontothe substrate There are some examples in DSSC applicationsuch as nanocrystalline TiO

2(efficiency of 240) [58]


Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2

Figure 13 Schematic of thermal spraying [47]

Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)

Filters for dust oil and humidity

Air compressorFlow meter

Powder feeders

X-Y stage

Valve

Figure 14 Schematic of NPDS [48]

TiO2films on ITO-PET substrates (efficiency of 280) [59]

and nanoporous microstructure of TiO2(efficiency of 710)

[57]

316 Nanoparticle Deposition System (NPDS) NPDS is anovel method that is used to deposit ceramic and metallicpowders on substrates at room temperature by sprayingparticles under low temperature and low vacuums andaccelerate particles to subsonic speeds (Figure 14) [48 60] Anovelmethodwas applied for the deposition of TiO

2powders

using Nanoparticle Deposition System (NPDS) for a dye-sensitized solar cell (DSSC) This method could overcomecertain limitations in the aerosol deposition method (ADM)

and cold gas dynamic spray method (CGDS) The ceramicpowder deposited on the substrate by ADM in vacuumcondition and metallic powder deposition requires a highpressure of carrier gas using the CGDS method The ADMmethod could not be used for metallic powder due to itslow particle velocity [61] This method could cover a widerange of materials using the supersonicsubsonic nozzle andlow-vacuum deposition conditions [60] Some advantagesfor this novel process are its viability at room temperaturesusceptibility to a variety of materials high deposition ratesand green fabrication without wet chemicals and binders[62] NPDS is used to fabricate DSSC for instance TiO

2

powders on indium tin oxide (ITO) coated polyethyleneterephthalate (PET) substrates (efficiency of 094) [63]


semiconducting TiO2powder on indium tin oxide (ITO)-

coated glass (efficiency of 124) [60] and crystalline TiO2

powders (efficiency of 280) [48]

4 Conclusions and Outlook

Taking into account the discussion at this point one can con-clude that the choice of method depends on parameters thatare regarded as important by the researchers For example iffilm adhesion forms the primary theme of the research thenthe thermal spraying and PVD-thermal evaporationmethodsare unsuitable If a substratewith a complex shape is subjectedto coating then the spin coating PVD-thermal evaporationandArc-PVDdonotmeet the proper criteria In addition thelimitations of precursorrsquos choice in PVD-thermal evaporationand DCMagnetron sputtering are rather obvious

The deposition methods are dependent on a variety ofconsideration and numerous criteria including thin filmapplicationsmaterial characteristics andprocess technologyThe best deposition lacks a clear guideline and has to takeinto account the limitations and advantages of differentpreparations and deposition technology in the context of thematerialsrsquo and substratesrsquo type specified application cost andrequested efficiency which could assist the researcher(s) inselecting a more appropriate procedure for their respectiveresearch

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgments

The authors would like to thank the UKMDLP-2013-015and GGPM-2012-027 Research Funds for providing financialsupport to this study

References

[1] N Asim K Sopian S Ahmadi et al ldquoA review on the roleof materials science in solar cellsrdquo Renewable and SustainableEnergy Reviews vol 16 pp 5834ndash5847 2012

[2] L Wang X Fang and Z Zhang ldquoDesign methods for largescale dye-sensitized solar modules and the progress of stabilityresearchrdquoRenewable and Sustainable EnergyReviews vol 14 no9 pp 3178ndash3184 2010

[3] Y-D Zhang X-M Huang D-M Li Y-H Luo and Q-BMeng ldquoHow to improve the performance of Dye-SensitizedSolar Cell modules by light collectionrdquo Solar Energy Materialsand Solar Cells vol 98 pp 417ndash423 2012

[4] Y-D Zhang X-M Huang Y-Y Yang et al ldquoHow to improvethe performance of dye-sensitized solar modules by ldquobackleadsrdquordquo Solar Energy Materials and Solar Cells vol 102 pp 109ndash113 2012

[5] F Bella R Bongiovanni R S Kumar M A Kulandainathanand A M Stephan ldquoLight cured networks containing metal

organic frameworks as efficient and durable polymer elec-trolytes for Dye-Sensitized Solar Cellsrdquo Journal of MaterialsChemistry A vol 1 pp 9033ndash9036 2013

[6] D Pugliese F Bella V Cauda et al ldquoA chemometric approachfor the sensitization procedure of ZnO flowerlike microstruc-tures for Dye-Sensitized Solar Cellsrdquo ACS Applied Materials ampInterfaces vol 5 pp 11288ndash11295 2013

[7] N Asim S AhmadiM A Alghoul F Y Hammadi K Saeedfarand K Sopian ldquoResearch and development aspects on chemicalpreparation techniques of photoanodes for dye Sensitized solarcellsrdquo Journal International Journal of Photoenergy vol 2014Article ID 518156 2014

[8] D B Hall P Underhill and J M Torkelson ldquoSpin coatingof thin and ultrathin polymer filmsrdquo Polymer Engineering andScience vol 38 no 12 pp 2039ndash2045 1998

[9] Pn Equipment Spin coater 2011[10] G A Luurtsema Spin Coating for Rectangular Substrates

Department of Electrical Engineering and Computer SciencesUniversity of California Berkeley Calif USA 1997

[11] F C Krebs ldquoFabrication and processing of polymer solar cellsa review of printing and coating techniquesrdquo Solar EnergyMaterials and Solar Cells vol 93 no 4 pp 394ndash412 2009

[12] P Yimsiri and M R MacKley ldquoSpin and dip coating oflight-emitting polymer solutions matching experiment withmodellingrdquo Chemical Engineering Science vol 61 no 11 pp3496ndash3505 2006

[13] K Antoine de F Angela F V Jerome P Adam and R PeterldquoColloidal CuInSe 2 nanocrystals thin films of low surfaceroughnessrdquo Advances in Natural Sciences Nanoscience andNanotechnology vol 4 Article ID 015004 2013

[14] LD Landau andBG Levich ldquoDragging of a liquid by amovingplaterdquo Acta Physicochim URSS vol 17 pp 42ndash54 1942

[15] M N Rahaman Ceramic Processing CRCTaylor amp FrancisBoca Raton Fla USA 2007

[16] L E Scriven ldquoPhysics and applications of DIP coating and spincoatingrdquoMRS Proceedings vol 121 p 717 1988

[17] T C Wei C C Wan and Y Y Wang ldquoPoly (N -vinyl-2-pyrrolidone)-capped platinum nanoclusters on indium-tinoxide glass as counterelectrode for Dye-Sensitized Solar CellsrdquoApplied Physics Letters vol 88 no 10 Article ID 103122 2006

[18] S Ito P Liska P Comte et al ldquoControl of dark current inphotoelectrochemical (TiO

2Iminus-I3) and Dye-Sensitized Solar

Cellsrdquo Chemical Communications no 34 pp 4351ndash4353 2005[19] C Industray Advanced Forming Advances in Tape Casting

Technology 2004[20] R Mens P Adriaensens L Lutsen et al ldquoNMR study of

the nanomorphology in thin films of polymer blends used inorganic PV devices MDMO-PPVPCBMrdquo Journal of PolymerScience A vol 46 no 1 pp 138ndash145 2008

[21] F Padinger C J Brabec T Fromherz J C Hummelen andN S Sariciftci ldquoFabrication of large area photovoltaic devicescontaining various blends of polymer and fullerene derivativesby using the doctor blade techniquerdquo Opto-Electronics Reviewvol 8 no 4 pp 280ndash283 2000

[22] C L Yu ldquoTitanium dioxide thick film printing paste for dyesensitized solar cellrdquo inMaterial Science and Engineering pp 1ndash75 Case Western Reserve University 2011

[23] S Ito P Chen P Comte et al ldquoFabrication of screen-printing pastes from TiO

2powders for dye-sensitised solar

cellsrdquo Progress in Photovoltaics Research and Applications vol15 no 7 pp 603ndash612 2007


[24] S Ito T N Murakami P Comte et al ldquoFabrication of thin filmdye sensitized solar cells with solar to electric power conversionefficiency over 10rdquoThin Solid Films vol 516 no 14 pp 4613ndash4619 2008

[25] T N Murakami S Ito Q Wang et al ldquoHighly efficientDye-Sensitized Solar Cells based on carbon black counterelectrodesrdquo Journal of the Electrochemical Society vol 153 no12 pp A2255ndashA2261 2006

[26] K KWong ANg X Y Chen et al ldquoEffect of ZnOnanoparticleproperties on Dye-Sensitized Solar Cell performancerdquo ACSApplied Materials and Interfaces vol 4 no 3 pp 1254ndash12612012

[27] H-M Cheng and W-F Hsieh ldquoElectron transfer properties oforganicDye-Sensitized Solar Cells based on indoline sensitizerswithZnOnanoparticlesrdquoNanotechnology vol 21 no 48 ArticleID 485202 2010

[28] L Chen W Tan J Zhang X Zhou X Zhang and Y LinldquoFabrication of high performance Pt counter electrodes onconductive plastic substrate for flexible Dye-Sensitized SolarCellsrdquo Electrochimica Acta vol 55 no 11 pp 3721ndash3726 2010

[29] S Ito N-L C Ha G Rothenberger et al ldquoHigh-efficiency(72) flexible Dye-Sensitized Solar Cells with Ti-metal sub-strate for nanocrystalline-TiO

2photoanoderdquo Chemical Com-

munications no 38 pp 4004ndash4006 2006[30] A Jaworek and A T Sobczyk ldquoElectrospraying route to nan-

otechnology an overviewrdquo Journal of Electrostatics vol 66 no3-4 pp 197ndash219 2008

[31] J C Swarbrick J B Taylor and J N OrsquoShea ldquoElectrospraydeposition in vacuumrdquo Applied Surface Science vol 252 no 15pp 5622ndash5626 2006

[32] S K Shah Application of Electrospray Deposition for Efficientand Stable Organic Photovoltaic Devices School of AdvanceStudies University of Camerino 2012

[33] X Li Y Zhang Z Zhang et al ldquoElectrospraying tuned photoan-ode structures for Dye-Sensitized Solar Cells with enhancedenergy conversion efficiencyrdquo Journal of Power Sources vol 196no 3 pp 1639ndash1644 2011

[34] G C Vougioukalakis T Stergiopoulos G Kantonis et alldquoTerpyridine- and 26-dipyrazinylpyridine-coordinated ruthe-nium(II) complexes synthesis characterization and applicationin TiO

2-based Dye-Sensitized Solar Cellsrdquo Journal of Photo-

chemistry and Photobiology A vol 214 no 1 pp 22ndash32 2010[35] R Chandrasekhar and K L Choy ldquoElectrostatic spray assisted

vapour deposition of fluorine doped tin oxiderdquo Journal ofCrystal Growth vol 231 no 1-2 pp 215ndash221 2001

[36] L Gonzalez-Garcıa J Idıgoras A R Gonzalez-Elipe A Bar-ranco and J A Anta ldquoCharge collection properties of Dye-Sensitized Solar Cells based on 1-dimensional TiO

2porous

nanostructures and ionic-liquid electrolytesrdquo Journal of Photo-chemistry and Photobiology A vol 241 pp 58ndash66 2012

[37] G Jimenez-Cadena E Comini M Ferroni A Vomiero andG Sberveglieri ldquoSynthesis of different ZnO nanostructures bymodified PVD process and potential use for Dye-SensitizedSolar CellsrdquoMaterials Chemistry and Physics vol 124 no 1 pp694ndash698 2010

[38] S Wang J Zhang S Chen et al ldquoConversion enhancementof flexible Dye-Sensitized Solar Cells based on TiO

2nanotube

arrays with TiO2nanoparticles by electrophoretic depositionrdquo

Electrochimica Acta vol 56 no 17 pp 6184ndash6188 2011[39] L Gonzalez-Garcıa I Gonzalez-Valls M Lira-Cantu A Bar-

ranco and A R Gonzalez-Elipe ldquoAligned TiO2nanocolumnar

layers prepared by PVD-GLAD for transparent dye sensitizedsolar cellsrdquo Energy and Environmental Science vol 4 no 9 pp3426ndash3435 2011

[40] M C Sharma B Tripathi S Kumar S Srivastava and Y KVijay ldquoLow cost CuInSe2 thin films production by stackedelemental layers process for large area fabrication of solar cellapplicationrdquoMaterials Chemistry and Physics vol 131 no 3 pp600ndash604 2012

[41] N S Xu and S E Huq ldquoNovel cold cathode materials andapplicationsrdquo Materials Science and Engineering R vol 48 no2-5 2005

[42] I P Jain and G Agarwal ldquoIon beam induced surface andinterface engineeringrdquo Surface Science Reports vol 66 no 3-4pp 77ndash172 2011

[43] A Barron ldquoApplying metallization by sputteringrdquo 2010httpcnxorgcontentm3380013

[44] HWender P Migowski A F Feil S R Teixeira and J DupontldquoSputtering deposition of nanoparticles onto liquid substratesrecent advances and future trendsrdquo Coordination ChemistryReviews vol 257 no 17-18 pp 2468ndash2248 2013

[45] H Pan S H Ko N Misra and C P Grigoropoulos ldquoLaserannealed composite titanium dioxide electrodes for Dye-Sensitized Solar Cells on glass and plasticsrdquo Applied PhysicsLetters vol 94 no 7 Article ID 071117 2009

[46] W-Y Ho M-H Chan K-S Yao C-L Chang D-Y Wangand C-H Hsu ldquoCharacteristics of chromium-doped titaniumoxide coatings synthesized by cathodic arc depositionrdquo ThinSolid Films vol 516 no 23 pp 8530ndash8536 2008

[47] T Zhang Y Bao and D T Gawne ldquoProcess model of plasmaenamellingrdquo Journal of the European Ceramic Society vol 23no 7 pp 1019ndash1026 2003

[48] Y-H Kim M-S Kim K-S Kim S-H Ahn and C S LeeldquoDeposition of TiO

2layers for Dye-Sensitized Solar Cells using

nano-particle deposition systemrdquo Current Applied Physics vol11 no 1 pp S122ndashS126 2011

[49] K Robbie and M J Brett ldquoSculptured thin films and glancingangle deposition growth mechanics and applicationsrdquo Journalof Vacuum Science and Technology A vol 15 no 3 pp 1460ndash1465 1997

[50] E Joanni R Savu M de Sousa Goes et al ldquoDye-SensitizedSolar Cell architecture based on indium-tin oxide nanowirescoated with titanium dioxiderdquo Scripta Materialia vol 57 no 3pp 277ndash280 2007

[51] F Fotsa-Ngaffo A P Caricato and F Romano ldquoOptical prop-erties of ITOTiO

2single and double layer thin films deposited

by RPLADrdquo Applied Surface Science vol 255 no 24 pp 9684ndash9687 2009

[52] F F Ngaffo A P Caricato M Fernandez M Martino and FRomano ldquoStructural properties of single and multilayer ITOand TiO

2films deposited by reactive pulsed laser ablation

deposition techniquerdquo Applied Surface Science vol 253 no 15pp 6508ndash6511 2007

[53] P A Lindfors W M Mularie and G K Wehner ldquoCathodic arcdeposition technologyrdquo Surface and Coatings Technology vol29 no 4 pp 275ndash290 1986

[54] S-F Wang K K Rao T C K Yang and H-P WangldquoInvestigation of nitrogen doped diamond like carbon films ascounter electrodes in dye sensitized solar cellsrdquo Journal of Alloysand Compounds vol 509 no 5 pp 1969ndash1974 2011

[55] C-H Chen K-C Chen and J-L He ldquoTransparent conductingoxide glass grownwith TiO

2-nanotube array for Dye-Sensitized


Solar CellrdquoCurrent Applied Physics vol 10 no 2 pp S176ndashS1792010

[56] X Cheng P Zeng S Hu T Kuang G Xie and F Gao ldquoPrepa-ration and characterization of TiO

2photoelectrode codoped

with aluminum and boron and its application inDye-SensitizedSolar Cellrdquo Rare Metals vol 25 no 6 pp 190ndash194 2006

[57] S-Q Fan C-J Li C-X Li G-J Liu G-J Yang and L-ZZhang ldquoPreliminary study of performance of Dye-SensitizedSolar Cell of nano-TiO

2coating deposited by vacuum cold

sprayingrdquo Materials Transactions vol 47 no 7 pp 1703ndash17092006

[58] S Q Fan C J Li G J Yang L Z Zhang J C Gao and Y XXi ldquoFabrication of nano-TiO

2coating for Dye-Sensitized Solar

Cell by vacuum cold spraying at room temperaturerdquo Journal ofThermal Spray Technology vol 16 pp 893ndash897 2007

[59] J Halme J Saarinen and P Lund ldquoSpray deposition andcompression of TiO

2nanoparticle films for Dye-Sensitized

Solar Cells on plastic substratesrdquo Solar Energy Materials andSolar Cells vol 90 no 7-8 pp 887ndash899 2006

[60] M-S Kim D-M Chun J-O Choi et al ldquoRoom temperaturedeposition of TiO

2using nano particle deposition system

(NPDS) Application to Dye-Sensitized Solar Cell (DSSC)rdquoInternational Journal of Precision Engineering and Manufactur-ing vol 12 no 4 pp 749ndash752 2011

[61] J Akedo ldquoAerosol deposition of ceramic thick films at roomtemperature densification mechanism of ceramic layersrdquo Jour-nal of the AmericanCeramic Society vol 89 no 6 pp 1834ndash18392006

[62] D M Chun M H Kim J C Lee and S H Ahn ldquoTiO2coating

on metal and polymer substrates by nano-particle depositionsystem (NPDS)rdquoCIRP AnnalsmdashManufacturing Technology vol57 no 1 pp 551ndash554 2008

[63] M S Kim D M Chun J O Choi et al ldquoDry-spray deposi-tion of TiO

2for a Flexible Dye-Sensitized Solar Cell (DSSC)

Using a Nanoparticle Deposition System (NPDS)rdquo Journal ofNanoscience and Nanotechnology vol 12 pp 3384ndash3388 2012

[64] P Suresh P Balaraju S K SharmaM S Roy andGD SharmaldquoPhotovoltaic devices based on PPHT ZnO and dye-sensitizedPPHT ZnO thin filmsrdquo Solar Energy Materials and Solar Cellsvol 92 no 8 pp 900ndash908 2008

[65] C S Chou C S Chou Y T Kuo and C P Wang ldquoPreparationof a working electrode with a conducting PEDOTPSS filmand its applications in a Dye-Sensitized Solar Cellrdquo AdvancedPowder Technology vol 24 pp 336ndash343 2013

[66] M McCune W Zhang and Y Deng ldquoHigh efficiency Dye-Sensitized Solar Cells based on three-dimensional multilayeredZnO nanowire arrays with ldquoCaterpillar-likeldquo structurerdquo NanoLetters vol 12 pp 3656ndash3662 2012

[67] S-Y Hsu C-H Tsai C-Y Lu et al ldquoNanoporous platinumcounter electrodes by glancing angle deposition for Dye-Sensitized Solar Cellsrdquo Organic Electronics vol 13 no 5 pp856ndash863 2012

[68] L J Larsen D D Tune P Kemppinen K N WinzenbergS E Watkins and J G Shapter ldquoIncreased performanceof single walled carbon nanotube photovoltaic cells throughthe addition of dibenzo[bdef]chrysene derivativerdquo Journal ofPhotochemistry and Photobiology A vol 235 pp 72ndash76 2012

[69] B Munkhbayar S Hwang J Kim et al ldquoPhotovoltaic perfor-mance of Dye-Sensitized Solar Cells with various MWCNTcounter electrode structures produced by different coatingmethodsrdquo Electrochimica Acta vol 80 pp 100ndash107 2012

[70] L Song P Du X Shao H Cao Q Hui and J Xiong ldquoEffects ofhydrochloric acid treatment of TiO

2nanoparticlesnanofibers

bilayer film on the photovoltaic properties of Dye-SensitizedSolar Cellsrdquo Materials Research Bulletin vol 48 pp 978ndash9822013

[71] W Zeng G Fang X Wang et al ldquoHierarchical porous nano-carbon composite effective fabrication and application in dyesensitized solar cellsrdquo Journal of Power Sources vol 229 pp 102ndash111 2013

[72] S H Park K H Shin J Y Kim et al ldquoThe applicationof camphorsulfonic acid doped polyaniline films prepared onTCO-free glass for counter electrode of bifacial Dye-SensitizedSolar Cellsrdquo Journal of Photochemistry and Photobiology A vol245 pp 1ndash8 2012

[73] J S Ni C Y Hung K Y Liu Y H Chang K C Ho andK F Lin ldquoEffects of tethering alkyl chains for amphiphilicruthenium complex dyes on their adsorption to titanium oxideand photovoltaic propertiesrdquo Journal of Colloid and InterfaceScience vol 386 pp 359ndash365 2012

[74] Z Qin Y Huang Q Liao Z Zhang X Zhang and Y ZhangldquoStability improvement of the ZnO nanowire array electrodemodified with Al

2O3and SiO

2for Dye-Sensitized Solar Cellsrdquo

Materials Letters vol 70 pp 177ndash180 2012[75] Z Qin Y Huang J Qi L Qu and Y Zhang ldquoImprovement

of the performance and stability of the ZnO nanoparticulatefilm electrode by surface modification for Dye-Sensitized SolarCellsrdquo Colloids and Surfaces A vol 386 no 1ndash3 pp 179ndash1842011

[76] C-C ChangM-T Jiang C-L Chang and C-L Lin ldquoPrepara-tion and characterization of poly(34-ethylenedioxythiophene)-poly(styrene sulfonate) composite thin films highly loaded withplatinum nanoparticlesrdquo Materials Chemistry and Physics vol127 no 3 pp 440ndash445 2011

[77] C-S Chou Y-J Lin R-Y Yang and K-H Liu ldquoPreparationof TiO

2NiO composite particles and their applications in Dye-

Sensitized Solar CellsrdquoAdvanced Powder Technology vol 22 no1 pp 31ndash42 2011

[78] Y Liu X Sun Q Tai et al ldquoEfficiency enhancement in Dye-Sensitized Solar Cells by interfacial modification of conductingglassmesoporous TiO

2using a novel ZnO compact blocking

filmrdquo Journal of Power Sources vol 196 no 1 pp 475ndash481 2011[79] Y Liu X Sun Q Tai et al ldquoInfluences on photovoltage

performance by interfacial modification of FTOmesoporousTiO2using ZnO andTiO

2as the compact filmrdquo Journal of Alloys

and Compounds vol 509 no 37 pp 9264ndash9270 2011[80] Y G Seo M A Kim H Lee and W Lee ldquoSolution processed

thin films of non-aggregated TiO2nanoparticles prepared by

mild solvothermal treatmentrdquo Solar Energy Materials and SolarCells vol 95 no 1 pp 332ndash335 2011

[81] C-M Chen H-S Shiu S-J Cherng and T-C Wei ldquoPrepara-tion of polymer film of micro-porous or island-like structureand its application in Dye-Sensitized Solar Cellrdquo Journal ofPower Sources vol 188 no 1 pp 319ndash322 2009

[82] W Hong Y Xu G Lu C Li and G Shi ldquoTransparentgraphenePEDOT-PSS composite films as counter electrodes ofDye-Sensitized Solar Cellsrdquo Electrochemistry Communicationsvol 10 no 10 pp 1555ndash1558 2008

[83] M Biancardo KWest and F C Krebs ldquoQuasi-solid-state Dye-Sensitized Solar Cells Pt and PEDOTPSS counter electrodesapplied to gel electrolyte assembliesrdquo Journal of Photochemistryand Photobiology A vol 187 no 2-3 pp 395ndash401 2007


[84] S H Kang J-Y Kim Y-K Kim and Y-E Sung ldquoEffects of theincorporation of carbon powder into nanostructured TiO

2film

for Dye-Sensitized Solar Cellrdquo Journal of Photochemistry andPhotobiology A vol 186 no 2-3 pp 234ndash241 2007

[85] N Fukuri Y Saito W Kubo et al ldquoPerformance improve-ment of solid-state Dye-Sensitized Solar Cells fabricated usingpoly(34-ethylenedioxythiophene) and amphiphilic sensitizingdyerdquo Journal of the Electrochemical Society vol 151 no 10 ppA1745ndashA1748 2004

[86] S Chappel and A Zaban ldquoNanoporous SnO2electrodes for

Dye-Sensitized Solar Cells improved cell performance by thesynthesis of 18 nm SnO

2colloidsrdquo Solar Energy Materials and

Solar Cells vol 71 no 2 pp 141ndash152 2002[87] J Liu Y Wang and D D Sun ldquoOleic acid-assisted exfoliated

few layer graphene films as counter electrode in Dye-SensitizedSolar Cellrdquo Journal of Alloys and Compounds vol 545 pp 99ndash104 2012

[88] I-K Ding J Melas-Kyriazi N-L Cevey-Ha et al ldquoDepositionof hole-transport materials in solid-state Dye-Sensitized SolarCells by doctor-bladingrdquo Organic Electronics vol 11 no 7 pp1217ndash1222 2010

[89] W Sun X Sun T Peng et al ldquoA low cost mesoporouscarbonSnO

2TiO2nanocomposite counter electrode for Dye-

Sensitized Solar Cellsrdquo Journal of Power Sources vol 201 pp402ndash407 2012

[90] S Ameen M S Akhtar H-K Seo Y S Kim and H SShin ldquoInfluence of Sn doping on ZnO nanostructures fromnanoparticles to spindle shape and their photoelectrochemicalproperties for dye sensitized solar cellsrdquo Chemical EngineeringJournal vol 187 pp 351ndash356 2012

[91] R Marczak F Werner R Ahmad V Lobaz D M Guldi andW Peukert ldquoDetailed investigations of ZnO photoelectrodespreparation for dye sensitized solar cellsrdquo Langmuir vol 27 no7 pp 3920ndash3929 2011

[92] K Miettunen M Toivola G Hashmi J Salpakari I Asgharand P Lund ldquoA carbon gel catalyst layer for the roll-to-rollproduction of dye solar cellsrdquo Carbon vol 49 no 2 pp 528ndash532 2011

[93] V M Guerin C Magne T Pauporte T Le Bahers and JRathousky ldquoElectrodeposited nanoporous versus nanopartic-ulate ZnO films of similar roughness for Dye-Sensitized SolarCell applicationsrdquo ACS Applied Materials and Interfaces vol 2no 12 pp 3677ndash3685 2010

[94] T Yamaguchi N Tobe D Matsumoto T Nagai and HArakawa ldquoHighly efficient plastic-substrate Dye-SensitizedSolar Cells with validated conversion efficiency of 76rdquo SolarEnergyMaterials and Solar Cells vol 94 no 5 pp 812ndash816 2010

[95] J Chen K Li Y Luo et al ldquoA flexible carbon counter electrodefor Dye-Sensitized Solar CellsrdquoCarbon vol 47 no 11 pp 2704ndash2708 2009

[96] K Li Y Luo Z YuMDengD Li andQMeng ldquoLow tempera-ture fabrication of efficient porous carbon counter electrode forDye-Sensitized Solar Cellsrdquo Electrochemistry Communicationsvol 11 no 7 pp 1346ndash1349 2009

[97] J H Park Y Jun H-G Yun S-Y Lee and M G KangldquoFabrication of an efficient Dye-Sensitized Solar Cell withstainless steel substraterdquo Journal of the Electrochemical Societyvol 155 no 7 pp F145ndashF149 2008

[98] L Yang Y Lin J Jia X Xiao X Li and X Zhou ldquoLightharvesting enhancement forDye-Sensitized SolarCells by novel

anode containing cauliflower-like TiO2spheresrdquo Journal of

Power Sources vol 182 no 1 pp 370ndash376 2008[99] X Liu Y Luo H Li et al ldquoRoom temperature fabrication of

porous ZnO photoelectrodes for flexible Dye-Sensitized SolarCellsrdquo Chemical Communications no 27 pp 2847ndash2849 2007

[100] T Miyasaka M Ikegami and Y Kijitori ldquoPhotovoltaic per-formance of plastic dye-sensitized electrodes prepared by low-temperature binder-free coating of mesoscopic titaniardquo Journalof the Electrochemical Society vol 154 no 5 pp A455ndashA4612007

[101] M Quintana T Edvinsson A Hagfeldt and G BoschlooldquoComparison of dye-sensitized ZnO and TiO

2solar cells

studies of charge transport and carrier lifetimerdquo Journal ofPhysical Chemistry C vol 111 no 2 pp 1035ndash1041 2007

[102] R Senadeera N Fukuri Y Saito T Kitamura Y Wada and SYanagida ldquoVolatile solvent-free solid-state polymer-sensitizedTiO2solar cells with poly(34-ethylenedioxythiophene) as a

hole-transporting mediumrdquo Chemical Communications no 17pp 2259ndash2261 2005

[103] Y Saito S Kambe T Kitamura Y Wada and S YanagidaldquoMorphology control of mesoporous TiO

2nanocrystalline

films for performance of Dye-Sensitized Solar Cellsrdquo SolarEnergy Materials and Solar Cells vol 83 no 1 pp 1ndash13 2004

[104] H Lindstrom A Holmberg E Magnusson L Malmqvistand A Hagfeldt ldquoA new method to make dye-sensitizednanocrystalline solar cells at room temperaturerdquo Journal ofPhotochemistry and Photobiology A vol 145 no 1-2 pp 107ndash1122001

[105] F Bella J R Nair and C Gerbaldi ldquoTowards green efficientand durable quasi-solid Dye-Sensitized Solar Cells integratedwith a cellulose-based gel-polymer electrolyte optimized by achemometric DoE approachrdquo RSC Advances vol 3 pp 15993ndash16001 2013

[106] Y Gong C Li X Huang et al ldquoSimple method for manufac-turing Pt counter electrodes on conductive plastic substrates forDye-Sensitized Solar CellsrdquoACS AppliedMaterials amp Interfacesvol 5 pp 795ndash800 2013

[107] A Umar ldquoGrowth of comb-like ZnO nanostructures for Dye-Sensitized Solar Cells applicationsrdquo Nanoscale Research Lettersvol 4 no 9 pp 1004ndash1008 2009

[108] L Guo Synthesis of zinc oxide fiber and its application in dyesensitized solar cells [MS thesis] Miami University OxfordOhio USA 2010

[109] S Futemvong A Pengpad N Hongsith DWongratanaphisanA Gardchareon and S Choopun ldquoEffect of nickel oxidethin films on photoconversion efficiency in zinc oxide Dye-Sensitized Solar Cellsrdquo Materials Science Forum vol 695 pp509ndash512 2011

[110] Y Wang Arrays of ZnO Nanowires for Photovoltaic DevicesDepartment of Physics and Materials Science City Universityof Hong Kong 2009

[111] C Y Neo and J Ouyang ldquoPrecise modification of the interfacebetween titanium dioxide and electrolyte of Dye-SensitizedSolar Cells with oxides deposited by thermal evaporation ofmetals and subsequent oxidationrdquo Journal of Power Sources vol196 no 23 pp 10538ndash10542 2011

[112] G J Fodjouong Y Feng M Sangare and X Huang ldquoSynthesisof ZnO nanostructure films by thermal evaporation approachand their application in Dye-Sensitized Solar Cellsrdquo MaterialsScience in Semiconductor Processing vol 16 pp 652ndash658 2013


[113] S Li X Zhang X Jiao and H Lin ldquoOne-step large-scalesynthesis of porous ZnO nanofibers and their application inDye-Sensitized Solar CellsrdquoMaterials Letters vol 65 no 19-20pp 2975ndash2978 2011

[114] B E Hardin W Gaynor I-K Ding S-B Rim P Peumansand M D McGehee ldquoLaminating solution-processed silvernanowiremesh electrodes onto solid-state Dye-Sensitized SolarCellsrdquo Organic Electronics vol 12 no 6 pp 875ndash879 2011

[115] F Bella E D Ozzello S Bianco and R Bongiovanni ldquoPhoto-polymerization of acrylicmethacrylic gelrsquopolymer electrolytemembranes for Dye-Sensitized Solar Cellsrdquo Chemical Engineer-ing Journal vol 225 pp 873ndash879 2013

[116] Y-G Kim C-H Shim D-H Kim H J Lee and H-JLee ldquoFabrication of transparent conductive oxide-less Dye-Sensitized Solar Cells consisting of Ti electrodes by electron-beam evaporation processrdquoThin Solid Films vol 520 no 6 pp2257ndash2260 2012

[117] H-B Kim D-W Park J-P Jeun S-H Oh Y-C Nho and P-HKang ldquoEffects of electron beam irradiation on the photoelectro-chemical properties of TiO

2film for DSSCsrdquo Radiation Physics

and Chemistry vol 81 pp 954ndash957 2012[118] M Manca F Malara L Martiradonna et al ldquoCharge recombi-

nation reduction in Dye-Sensitized Solar Cells by means of anelectron beam-deposited TiO

2buffer layer between conductive

glass and photoelectroderdquoThin Solid Films vol 518 no 23 pp7147ndash7151 2010

[119] M Shaheer Akhtar D-J Choi S-K Lee andO-B Yang ldquoEffectof electron beam irradiation on the electrochemical propertiesof heteropolyacid-polyethylene oxide composite electrolyte forDye-Sensitized Solar Cellrdquo Current Applied Physics vol 10 no2 pp S161ndashS164 2010

[120] M K Parvez G M Yoo J H Kim M J Ko and S RKim ldquoComparative study of plasma and ion-beam treatment toreduce the oxygen vacancies in TiO

2and recombination reac-

tions in Dye-Sensitized Solar Cellsrdquo Chemical Physics Lettersvol 495 no 1ndash3 pp 69ndash72 2010

[121] G K Kiema M J Colgan andM J Brett ldquoDye sensitized solarcells incorporating obliquely deposited titanium oxide layersrdquoSolar Energy Materials and Solar Cells vol 85 no 3 pp 321ndash331 2005

[122] M-S Wong M-F Lee C-L Chen and C-H Huang ldquoVapordeposited sculptured nano-porous titania films by glancingangle deposition for efficiency enhancement in Dye-SensitizedSolar CellsrdquoThin Solid Films vol 519 no 5 pp 1717ndash1722 2010

[123] H-Y Yang M-F Lee C-H Huang Y-S Lo Y-J Chen andM-S Wong ldquoGlancing angle deposited titania films for Dye-Sensitized Solar CellsrdquoThin Solid Films vol 518 no 5 pp 1590ndash1594 2009

[124] B-L Chen H Hu Q-D Tai et al ldquoAn inverted fabricationmethod towards a flexible dye sensitized solar cell based on afree-standing TiO

2nanowires membranerdquo Electrochimica Acta

vol 59 pp 581ndash586 2012[125] R Gazia A Chiodoni S Bianco et al ldquoAn easy method for

the room-temperature growth of spongelike nanostructured Znfilms as initial step for the fabrication of nanostructured ZnOrdquoThin Solid Films vol 524 pp 107ndash112 2012

[126] O LupanVMGuerin LGhimpu IM Tiginyanu andT Pau-porte ldquoNanofibrous-like ZnO layers deposited by magnetronsputtering and their integration in Dye-Sensitized Solar CellsrdquoChemical Physics Letters vol 550 pp 125ndash129 2012

[127] H Seo M K Son S Park H J Kim and M Shiratani ldquoTheblocking effect of charge recombination by sputtered and acid-treated ZnO thin film in Dye-Sensitized Solar Cellsrdquo Journal ofPhotochemistry and Photobiology A vol 248 pp 50ndash54 2012

[128] B Yoo M K Lim and K-J Kim ldquoApplication of Pt sputter-deposited counter electrodes based on micro-patterned ITOglass to quasi-solid state Dye-Sensitized Solar Cellsrdquo CurrentApplied Physics vol 12 pp 1302ndash1306 2012

[129] J KimH Choi C Nahm et al ldquoThe effect of a blocking layer onthe photovoltaic performance in CdS quantum-dot-sensitizedsolar cellsrdquo Journal of Power Sources vol 196 no 23 pp 10526ndash10531 2011

[130] MA Bissett I Koper J SQuinton and JG Shapter ldquoDendrongrowth from vertically aligned single-walled carbon nanotubethin layer arrays for photovoltaic devicesrdquo Physical ChemistryChemical Physics vol 13 no 13 pp 6059ndash6064 2011

[131] W Chen Y Qiu K Yan and S Yang ldquoSurfactant directedself-assembly of size-tunable mesoporous titanium dioxidemicrospheres and their application in quasi-solid state Dye-Sensitized Solar Cellsrdquo Journal of Power Sources vol 196 no24 pp 10806ndash10816 2011

[132] L-Y Lin C-P Lee R V Rvittal and K-C Ho ldquoImprovingthe durability of Dye-Sensitized Solar Cells through backilluminationrdquo Journal of Power Sources vol 196 no 3 pp 1671ndash1676 2011

[133] K Miettunen I Asghar X Ruan J Halme T Saukkonen andP Lund ldquoStabilization of metal counter electrodes for dye solarcellsrdquo Journal of Electroanalytical Chemistry vol 653 no 1-2 pp93ndash99 2011

[134] Y S Park and H-K Kim ldquoThe effects of annealing temperatureon the characteristics of carbon counter electrodes for Dye-Sensitized Solar Cellsrdquo Current Applied Physics vol 11 no 4pp 989ndash994 2011

[135] C-C Yang H Q Zhang and Y R Zheng ldquoDSSC with a novelPt counter electrodes using pulsed electroplating techniquesrdquoCurrent Applied Physics vol 11 no 1 pp S147ndashS153 2011

[136] M-H Yeh C-P Lee L-Y Lin et al ldquoA composite poly(33-diethyl-34-dihydro-2H-thieno-[34-b][14]-dioxepine) and Ptfilm as a counter electrode catalyst in Dye-Sensitized SolarCellsrdquo Electrochimica Acta vol 56 no 17 pp 6157ndash6164 2011

[137] Y-L Lee C-L Chen L-W Chong C-H Chen Y-F Liuand C-F Chi ldquoA platinum counter electrode with high elec-trochemical activity and high transparency for Dye-SensitizedSolarCellsrdquoElectrochemistry Communications vol 12 no 11 pp1662ndash1665 2010

[138] D D Tune B S Flavel J S Quinton A V Ellis and J GShapter ldquoSingle walled carbon nanotube network electrodes fordye solar cellsrdquo Solar Energy Materials and Solar Cells vol 94no 10 pp 1665ndash1672 2010

[139] H Chang and Y-J Lo ldquoPomegranate leaves and mulberryfruit as natural sensitizers for Dye-Sensitized Solar Cellsrdquo SolarEnergy vol 84 no 10 pp 1833ndash1837 2010

[140] M F Hossain and T Takahashi ldquoMicrostructured ZnO pho-toelectrode grown on the sputter-deposited ZnO passivating-layer for improving the photovoltaic performancesrdquo MaterialsChemistry and Physics vol 124 no 2-3 pp 940ndash945 2010

[141] C-H Zhou Y Yang J Zhang et al ldquoEnhanced electrochemicalperformance of the counterelectrode of dye sensitized solar cellsby sandblastingrdquo Electrochimica Acta vol 54 no 23 pp 5320ndash5325 2009


[142] S Biswas M F Hossain and T Takahashi ldquoFabrication ofGratzel solar cell with TiO

2CdS bilayered photoelectroderdquo

Thin Solid Films vol 517 no 3 pp 1284ndash1288 2008[143] M FHossain S Biswas andTTakahashi ldquoThe effect of sputter-

deposited TiO2passivating layer on the performance of Dye-

Sensitized Solar Cells based on sol-gel derived photoelectroderdquoThin Solid Films vol 517 no 3 pp 1294ndash1300 2008

[144] H Gao G Fang M Wang et al ldquoThe effect of growthconditions on the properties of ZnO nanorod Dye-SensitizedSolarCellsrdquoMaterials Research Bulletin vol 43 no 12 pp 3345ndash3351 2008

[145] Y-M Sung and D-W Han ldquoTransparent conductive titanium-doped indium oxide films prepared by a magnetic null dis-charge sputter sourcerdquo Vacuum vol 83 no 1 pp 161ndash165 2008

[146] J Xia N Masaki K Jiang and S Yanagida ldquoDeposition ofa thin film of TiOx from a titanium metal target as novelblocking layers at conducting glassTiO

2interfaces in ionic

liquid mesoscopic TiO2Dye-Sensitized Solar Cellsrdquo Journal of

Physical Chemistry B vol 110 no 50 pp 25222ndash25228 2006[147] M K Nazeeruddin F De Angelis S Fantacci et al ldquoCom-

bined experimental and DFT-TDDFT computational study ofphotoelectrochemical cell ruthenium sensitizersrdquo Journal of theAmerican Chemical Society vol 127 no 48 pp 16835ndash168472005

[148] T Ma X Fang M Akiyama K Inoue H Noma and E AbeldquoProperties of several types of novel counter electrodes for Dye-Sensitized Solar Cellsrdquo Journal of Electroanalytical Chemistryvol 574 no 1 pp 77ndash83 2004

[149] K Imoto K Takahashi T Yamaguchi T Komura J-I Naka-mura and K Murata ldquoHigh-performance carbon counterelectrode forDye-Sensitized Solar Cellsrdquo Solar EnergyMaterialsand Solar Cells vol 79 no 4 pp 459ndash469 2003

[150] Y Saito T Kitamura Y Wada and S Yanagida ldquoApplication ofpoly(34-ethylenedioxythiophene) to counter electrode in Dye-Sensitized Solar Cellsrdquo Chemistry Letters no 10 pp 1060ndash10612002

[151] Y T Kim J Park and J Choi ldquoSputter-deposited ZnO thin filmsconsisting of nano-networks for binder-free Dye-SensitizedSolar Cellsrdquo Current Applied Physics vol 13 pp 381ndash385 2013

[152] M K Son H Seo S K Kim et al ldquoImproved long-term dura-bility of a parallel-type Dye-Sensitized Solar Cell module usinga platinum metal grid fabricated by direct current magnetronsputtering with heat treatmentrdquo Journal of Power Sources vol222 pp 333ndash339 2013

[153] H-J Kim J-D Jeon D Y Kim J-J Lee and S-Y KwakldquoImproved performance of Dye-Sensitized Solar Cells withcompact TiO

2blocking layer prepared using low-temperature

reactive ICP-assisted DC magnetron sputteringrdquo Journal ofIndustrial and Engineering Chemistry vol 18 pp 1807ndash18122012

[154] P Chen and W Y Wu ldquoThe use of sputter deposited TiN thinfilm as a surface conducting layer on the counter electrode offlexible plastic Dye-Sensitized Solar Cellsrdquo Surface and CoatingsTechnology vol 231 pp 140ndash143 2013

[155] H Wang H Li J Wang and J Wu ldquoHigh aspect-ratiotransparent highly ordered titanium dioxide nanotube arraysand their performance in dye sensitized solar cellsrdquo MaterialsLetters vol 80 pp 99ndash102 2012

[156] M Awais M Rahman J M Don MacElroy et al ldquoDepositionand characterization of NiOx coatings bymagnetron sputtering

for application in Dye-Sensitized Solar Cellsrdquo Surface andCoatings Technology vol 204 no 16-17 pp 2729ndash2736 2010

[157] L Li R Chen G Jing G Zhang F Wu and S ChenldquoImproved performance of TiO

2electrodes coated with NiO by

magnetron sputtering for Dye-Sensitized Solar Cellsrdquo AppliedSurface Science vol 256 no 14 pp 4533ndash4537 2010

[158] L Meng T Ren and C Li ldquoThe control of the diameter of thenanorods prepared by dc reactivemagnetron sputtering and theapplications for DSSCrdquo Applied Surface Science vol 256 no 11pp 3676ndash3682 2010

[159] V Senthilkumar M Jayachandran and C Sanjeeviraja ldquoPrepa-ration of anatase TiO

2thin films for Dye-Sensitized Solar Cells

by DC reactive magnetron sputtering techniquerdquo Thin SolidFilms vol 519 no 3 pp 991ndash994 2010

[160] S Sutthana N Hongsith and S Choopun ldquoAZOAgAZOmultilayer films prepared byDCmagnetron sputtering for Dye-Sensitized Solar Cell applicationrdquo Current Applied Physics vol10 no 3 pp 813ndash816 2010

[161] S MWaita B O Aduda J MMwabora G A Niklasson C GGranqvist and G Boschloo ldquoElectrochemical characterizationof TiO

2blocking layers prepared by reactive DC magnetron

sputteringrdquo Journal of Electroanalytical Chemistry vol 637 no1-2 pp 79ndash83 2009

[162] M F Hossain S Biswas T Takahashi Y Kubota and AFujishima ldquoInvestigation of sputter-deposited TiO

2thin film

for the fabrication of Dye-Sensitized Solar Cellsrdquo Thin SolidFilms vol 516 no 20 pp 7149ndash7154 2008

[163] S Wu H Han Q Tai et al ldquoImprovement in Dye-SensitizedSolar Cells employing TiO

2electrodes coated with Al

2O3by

reactive direct current magnetron sputteringrdquo Journal of PowerSources vol 182 no 1 pp 119ndash123 2008

[164] NHirahara BOnwona-Agyeman andMNakao ldquoPreparationof Al-doped ZnO thin films as transparent conductive substratein Dye-Sensitized Solar Cellrdquo Thin Solid Films vol 520 no 6pp 2123ndash2127 2012

[165] Y-S Jin K-H Kim W-J Kim K-U Jang and H-W ChoildquoThe effect of RF-sputtered TiO

2passivating layer on the per-

formance of dye sensitized solar cellsrdquo Ceramics Internationalvol 38 no 1 pp S505ndashS509 2012

[166] G Perez-Hernandez A Vega-Poot I Perez-Juarez et al ldquoEffectof a compact ZnO interlayer on the performance of ZnO-basedDye-Sensitized Solar Cellsrdquo Solar Energy Materials and SolarCells vol 100 pp 21ndash26 2012

[167] J-A Jeong and H-K Kim ldquoThickness effect of RF sputteredTiO2passivating layer on the performance of Dye-Sensitized

Solar Cellsrdquo Solar Energy Materials and Solar Cells vol 95 no1 pp 344ndash348 2011

[168] D-J Kwak J-H Kim B-W Park Y-M Sung M-W Park andY-B Choo ldquoGrowth of ZnOAl transparent conducting layer onpolymer substrate for flexible film typed Dye-Sensitized SolarCellrdquoCurrent Applied Physics vol 10 no 2 pp S282ndashS285 2010

[169] S-H PaengM-W Park andY-M Sung ldquoTransparent conduc-tive characteristics of TiITO films deposited by RF magnetronsputtering at low substrate temperaturerdquo Surface and CoatingsTechnology vol 205 supplement 1 pp S210ndashS215 2010

[170] H K Singh D C Agarwal P M Chavhan et al ldquoStudy ofswift heavy ion irradiation effect on indium tin oxide coatedelectrode for the Dye-Sensitized Solar Cell applicationrdquoNuclearInstruments and Methods in Physics Research B vol 268 no 19pp 3223ndash3226 2010


[171] L-T Huang M-C Lin M-L Chang R-R Wang and H-CLin ldquoThin film encapsulation of DSSCs on plastic substraterdquoThin Solid Films vol 517 no 14 pp 4207ndash4210 2009

[172] B Yoo K Kim S H Lee W M Kim and N-G ParkldquoITOATOTiO

2triple-layered transparent conducting sub-

strates for Dye-Sensitized Solar Cellsrdquo Solar Energy Materialsand Solar Cells vol 92 no 8 pp 873ndash877 2008

[173] J-Y Choi J-T Hong H Seo et al ldquoOptimal series-parallelconnectionmethod of Dye-Sensitized Solar Cell for Pt thin filmdeposition using a radio frequency sputter systemrdquo Thin SolidFilms vol 517 no 2 pp 963ndash966 2008

[174] S H Kang M-S Kang H-S Kim et al ldquoColumnar rutileTiO2based Dye-Sensitized Solar Cells by radio-frequency

magnetron sputteringrdquo Journal of Power Sources vol 184 no1 pp 331ndash335 2008

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal ofPhotoenergy


Carbohydrate Chemistry

International Journal of


Journal of

Chemistry


Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of


Chromatography Research International


Applied ChemistryJournal of



Theoretical ChemistryJournal of


Journal of

Spectroscopy

Analytical ChemistryInternational Journal of


Journal of


Quantum Chemistry


Organic Chemistry International

ElectrochemistryInternational Journal of



CatalystsJournal of


2 Physical Methods

Physical methods utilize physical phenomenon to prepareand deposit the materials Physical methods are furthercategorized according to their medium or precursors suchas gas or liquid We tried to categorize these methods byconsidering this concept although it does overlap from timeto time

21 Liquid Phase Precursors

211 Spin Coating Uniform thin films on flat substratesare deposited via the spin coating method which encom-passes products such as thin and ultrathin polymer filmsProcedures on spin coating include deposition spinupspinoff and evaporation (Figure 1) The overloaded solutionis deposited onto the substrate rotated at high speeds andfinally the solution coats the substrate via centrifugal forceThe desired thickness is obtained by continuous rotationThe solvent being volatile simultaneously evaporates Thefilmrsquos thickness is dependent on the solutionrsquos concentrationsolvent and spin speeds [8] The thin film is deposited by thehigh angular spin speedThe thickness of the films is less than10 nm which is useful in microfabrication and photolithog-raphy which requires the thickness of the photoresist to becirca 1 micrometer The film thickness is explained as follows[9]

ℎ = (1 minus120588119860

1205881198600

) sdot (3120578 sdot 119898

212058811986001205962)

(13)

(1)

where ℎ is thickness 120588119860is density of volatile liquid 120578 is

solution viscosity m is evaporation rate and 120596 is angularspeed For the experimental results ℎ = 119860120596minus119861 can be usedwhere119860 and119861 are constant parameters and119861 = 04 and 07 inmost casesThe desired thickness uniformfilm simple setupand low power consumption are some of the advantages ofthis method However its dependence of the substratersquos sizeof the spin coating process the lack of material sufficiencyhigh cost and its requirement for a flat substrate are some ofits known disadvantages [10] As can be seen in Table 1 thelist of materials could be used via the spin coating method inDSSC application

212 Dip Coating Dip coating results in a uniform thin filmof liquid deposition upon the substrate for small slabs andcylinders (Figure 2)The thickness of the film depends on theviscous force capillary (surface tension) force and gravityThe flow conditions of the liquid bath and gas overheadplay an important role in both thicknesses and uniformitiesThicker films resulted fromusing volatile solutes and combin-ing rapid sufficient drying via basic liquid flow The growththeoretical prediction and control of the process representsome of the challenges faced when utilizing this method Ifthe withdrawal speed is chosen in a way that the sheer ratesremain with the Newtonian regime the thickness deposition

Air flow

Radial liquid

Liquid film

Evaporation

Angular velocity

Radial liquid

Disk

flowflow

Figure 1 Spin coating procedure [11]

can be calculated by the Landau-Levich equation as follows[14]

ℎ = 094 sdot(120578 sdot V)23

12057416

LV (120588 sdot 119892)12 (2)

where h is coating thickness 120578 is viscosity V is dragging speed120574LV is liquid-vapor surface tension 120588 is density and 119892 is thegravity constant

The dip coating process is divided into five steps [15] (1)Immersion the substrate is immersed in the coating materialsolution at a consistent speed for a moment and (2) startupthe substrate is subsequently pulled up which precipitates theformation of a thin layer to formon the substrate Pullingup isperformed at a steady speed to eliminate any potential jitters(3) Deposition the thickness of the coating is controlled bythe pull speed as a thicker coating will form if the pull (with-drawal) speed is increased If a thinner layer is required then(4) drainage the excess liquid is drained and (5) evaporationany remaining solution on the coating is evaporated usingvolatile solvents such as alcohols This step is continuouslyrepeated The dip coating method is rather common whilethe spin coating method that was previously discussed ismore suitable for industrial purposes [16] The dip coatingmethod is used in DSSC applications such as Poly(N-vinyl-2-pyrrolidone)-capped platinum nanoclusters deposited onindium tin oxide glass (efficiency 284) [17] and meso-porousTiO

2films deposited on an F-doped tin oxidewith dye

(ruthenium complex bis-tetrabutylammoniumcis-dithiocya-nato-N1198731015840-bis-221015840-bipyridine-4-carboxylic acid 41015840-carbox-ylate ruthenium(II)) (efficiency 1080) [18]

213 Doctor Blade Printing (Knife to Edge) Roll to RollCeramic capacitors are the first recorded tape-castingmachines that were made by Glen Howatt [19] and this mar-velous invention is soon followed by the doctor blade or tapecastingmethodThemultilayer ceramic capacitors (MLCCs)low temperature cofired ceramics (LTCCs) lithium batteriesfuel cells oxygen separators and thermistors are some of thedevices that are manufactured by the tape casting methodThe application of thismethod vis-a-vis thin films is relativelyrecent which found its niche in nanotechnological advances





Texture analyzer

Substrate

Solution

(a) (b)

(c)



(a)

Solution deposition

Colloidal solution

Glass substrate

Solution spreading

Blade

Film drying1

of NCs

2 3

(b)












830 [97]


TiO2 porous film


[104]







2particles)











Screen with

Ink

Squeegee

Printed ink

Frame

with ink

emulsion

Substrate


HV

Particle suspension

Capillary

Substrate

Electrospray

(a)

HV

Particle precursor

Capillary

Substrate

Electrospray

Heating element

(b)



2

















Reference









Vaporized material

Substrate


Source material

Evaporator

Vacuum chamber

Heater



Substrate

Radiation heating



Evaporant










701 [118]


340 [119]



X-ray emission

Sputtered atomsions

Hollow atom

Electrons

Incoming ionq+




Substrates

Target


Glowdischarge


Plasma region

Gas in

Vacu

um ch

ambe

r

High vacuum pump

Low vacuum pump

Sample holder

Power supply

Sample

MagnetronTarget

DC RF

(minus)

(+)

Gas in



















Reference







500 [171]






2electrodes


2single and double



2-





Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





Texture analyzer

Substrate

Solution

(a) (b)

(c)



(a)

Solution deposition

Colloidal solution

Glass substrate

Solution spreading

Blade

Film drying1

of NCs

2 3

(b)












830 [97]


TiO2 porous film


[104]







2particles)











Screen with

Ink

Squeegee

Printed ink

Frame

with ink

emulsion

Substrate


HV

Particle suspension

Capillary

Substrate

Electrospray

(a)

HV

Particle precursor

Capillary

Substrate

Electrospray

Heating element

(b)



2

















Reference









Vaporized material

Substrate


Source material

Evaporator

Vacuum chamber

Heater



Substrate

Radiation heating



Evaporant










701 [118]


340 [119]



X-ray emission

Sputtered atomsions

Hollow atom

Electrons

Incoming ionq+




Substrates

Target


Glowdischarge


Plasma region

Gas in

Vacu

um ch

ambe

r

High vacuum pump

Low vacuum pump

Sample holder

Power supply

Sample

MagnetronTarget

DC RF

(minus)

(+)

Gas in



















Reference







500 [171]






2electrodes


2single and double



2-





Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


(a)

Solution deposition

Colloidal solution

Glass substrate

Solution spreading

Blade

Film drying1

of NCs

2 3

(b)












830 [97]


TiO2 porous film


[104]







2particles)











Screen with

Ink

Squeegee

Printed ink

Frame

with ink

emulsion

Substrate


HV

Particle suspension

Capillary

Substrate

Electrospray

(a)

HV

Particle precursor

Capillary

Substrate

Electrospray

Heating element

(b)



2

















Reference









Vaporized material

Substrate


Source material

Evaporator

Vacuum chamber

Heater



Substrate

Radiation heating



Evaporant










701 [118]


340 [119]



X-ray emission

Sputtered atomsions

Hollow atom

Electrons

Incoming ionq+




Substrates

Target


Glowdischarge


Plasma region

Gas in

Vacu

um ch

ambe

r

High vacuum pump

Low vacuum pump

Sample holder

Power supply

Sample

MagnetronTarget

DC RF

(minus)

(+)

Gas in



















Reference







500 [171]






2electrodes


2single and double



2-





Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of






830 [97]


TiO2 porous film


[104]







2particles)











Screen with

Ink

Squeegee

Printed ink

Frame

with ink

emulsion

Substrate


HV

Particle suspension

Capillary

Substrate

Electrospray

(a)

HV

Particle precursor

Capillary

Substrate

Electrospray

Heating element

(b)



2

















Reference









Vaporized material

Substrate


Source material

Evaporator

Vacuum chamber

Heater



Substrate

Radiation heating



Evaporant










701 [118]


340 [119]



X-ray emission

Sputtered atomsions

Hollow atom

Electrons

Incoming ionq+




Substrates

Target


Glowdischarge


Plasma region

Gas in

Vacu

um ch

ambe

r

High vacuum pump

Low vacuum pump

Sample holder

Power supply

Sample

MagnetronTarget

DC RF

(minus)

(+)

Gas in



















Reference







500 [171]






2electrodes


2single and double



2-





Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of



Screen with

Ink

Squeegee

Printed ink

Frame

with ink

emulsion

Substrate


HV

Particle suspension

Capillary

Substrate

Electrospray

(a)

HV

Particle precursor

Capillary

Substrate

Electrospray

Heating element

(b)



2

















Reference









Vaporized material

Substrate


Source material

Evaporator

Vacuum chamber

Heater



Substrate

Radiation heating



Evaporant










701 [118]


340 [119]



X-ray emission

Sputtered atomsions

Hollow atom

Electrons

Incoming ionq+




Substrates

Target


Glowdischarge


Plasma region

Gas in

Vacu

um ch

ambe

r

High vacuum pump

Low vacuum pump

Sample holder

Power supply

Sample

MagnetronTarget

DC RF

(minus)

(+)

Gas in



















Reference







500 [171]






2electrodes


2single and double



2-





Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of




Reference









Vaporized material

Substrate


Source material

Evaporator

Vacuum chamber

Heater



Substrate

Radiation heating



Evaporant










701 [118]


340 [119]



X-ray emission

Sputtered atomsions

Hollow atom

Electrons

Incoming ionq+




Substrates

Target


Glowdischarge


Plasma region

Gas in

Vacu

um ch

ambe

r

High vacuum pump

Low vacuum pump

Sample holder

Power supply

Sample

MagnetronTarget

DC RF

(minus)

(+)

Gas in



















Reference







500 [171]






2electrodes


2single and double



2-





Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





701 [118]


340 [119]



X-ray emission

Sputtered atomsions

Hollow atom

Electrons

Incoming ionq+




Substrates

Target


Glowdischarge


Plasma region

Gas in

Vacu

um ch

ambe

r

High vacuum pump

Low vacuum pump

Sample holder

Power supply

Sample

MagnetronTarget

DC RF

(minus)

(+)

Gas in



















Reference







500 [171]






2electrodes


2single and double



2-





Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of
















Reference







500 [171]






2electrodes


2single and double



2-





Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of



Homogenizer


Receivingsubstrate

Collision nebulizer

Flow meter

Carrier gas




Pumpingsystem

Specimen

Trigger

Holder

Trigger


Gas in (O2)

Power

(+)

(minus)

(+)

(minus)

Pulse power

supply

supply

Power supply






Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


Ar

Substrate

Deposit

Plasma

Powder 2

Powder 1

Plasma torch

+

minus

H2


Powderfilter

Vacuum pump

Vacuum chamber

Substrate

Nozzle

Controller(PMAC PC)



Powder feeders

X-Y stage

Valve




[57]


2powders



2











Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of










Acknowledgments


References















































2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of



















2porous




2nanotube
































































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





































2O3and SiO





















2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of



2film


























2solar cells





2nanocrystalline






















































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of












































































2thin film




2O3by





























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


















Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of

The Role of Physical Techniques on the Preparation of Photoanodes for Dye Sensitized Solar Cells

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Transcript of The Role of Physical Techniques on the Preparation of Photoanodes for Dye Sensitized Solar Cells