cross section sem

7232019 Cross Section SEM

httpslidepdfcomreaderfullcross-section-sem 19

Hindawi Publishing CorporationInternational Journal o Photoenergy Volume 983090983088983089983091 Article ID 983090983096983088983090983093983091 983096 pageshttpdxdoiorg983089983088983089983089983093983093983090983088983089983091983090983096983088983090983093983091

Research ArticleDye-Sensitized Solar Cells with Anatase TiO2

Nanorods Prepared by Hydrothermal Method

Ming-Jer Jeng1 Yi-Lun Wung1 Liann-Be Chang1 and Lee Chow 2

983089 Department of Electronic Engineering and Green echnology Research Center Chang-Gung University aoyuan 983091983091983091 aiwan983090 Department of Physics University of Central Florida Orlando FL 983091983090983096983089983094 USA

Correspondence should be addressed to Ming-Jer Jeng mjjengmailcguedutw

Received 983090983097 June 983090983088983089983091 Revised 983090983088 August 983090983088983089983091 Accepted 983094 September 983090983088983089983091

Academic Editor Steano Caramori

Copyright copy 983090983088983089983091 Ming-Jer Jeng et al Tis 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

Te hydrothermal method provides an effective reaction environment or the synthesis o nanocrystalline materials with highpurity and well-controlled crystallinity In this work we started with various sizes o commercial iO

2 powders and used the

hydrothermal method to prepare iO2 thin 1047297lms We ound that the synthesized iO

2 nanorods were thin and long when smaller

iO2 particles wereused while larger iO

2 particlesproduced thicker andshorter nanorodsWe alsoound thatiO

2 1047297lmsprepared

by iO2 nanorods exhibited larger surace roughness than those prepared by the commercial iO

2 particles It was ound that a

pure anatase phase o iO2

nanorods can be obtained rom the hydrothermal method Te dye-sensitized solar cells abricatedwith iO

2 nanorods exhibited a higher solar efficiency than those abricated with commercial iO

2 nanoparticles directly Further

triple-layer structures o iO2 thin 1047297lms with different particle sizes were investigated to improve the solar efficiency

1 Introduction

Dye-sensitized solarcells (DSSCs) have attracted muchatten-tion as possible candidates or low cost high stability andhigh efficient solar cells [983089 983090] Tere are many innovationsin this emerging technology such as new dyes which areabsorbed at a wider range o wavelengths and the intro-duction o nanostructure titanium oxides (iO

2) to increase

the surace area [983091ndash983093] Te DSSCs with the nanostructuretitanium oxidePorphyrins dye thin 1047297lms on transparent

conducting oxide- (CO-) coated glass can achieve a solarefficiency as high as 983089983091 [983094] Te major improvements o theresearch are made not only by introducing highly absorbingdyes as light harvesters but also by using the nanostructurelayer to improve the absorption and collection efficiencyIn principle ast electron transport and slow recombinationwill be needed to obtain a high solar conversion efficiencyFor conventional DSSC the mesoporous 1047297lm consisted o nanocrystalline iO

2 particles enjoying the advantages o

a large surace or greater dye adsorption and acilitatingelectrolyte diffusion within their pores [983095ndash983089983090] Te hydrother-mal method provides an effective reaction environment orthe synthesis o nanocrystalline iO

2 with high purity and

well-controlled crystallinity [983089983091ndash983089983093] Tereore we use thehydrothermal method to prepare iO

2thin 1047297lmsin this work

Te aguchi method [983089983094ndash983090983088] is used to 1047297nd the optimalparameters or the ormation o high-quality iO

2 1047297lms Te

aguchi method [983089983094] is a process optimization technique thatinvestigates how multiparameters affect the perormance o aprocess It can minimize the variation in a process throughrobust design o experiments Te aguchi method usesorthogonal arrays [983089983095] to organize the parameters affecting

the process and the levels at which they should be variedIt allows or the determination o actors mostly affecting aprocess perormance characteristic with a minimum amounto experimentation Generally it employs a generic signal-to-noise (1038389) ratio to quantiy the variation Tese 1038389ratios are used as measures o the effect o noise actors onperormancecharacteristics Tereare several1038389 ratio typeso characteristics larger is better nominal is best smaller isbetter and so orth [983089983094 983089983096]

In addition it is known that the strong back-scatteringlight due to the large particles near the conducting glassresults in a light loss o reduce light loss due to this strongback-scattering light multiple-layer structure o iO

2 with



983090 International Journal o Photoenergy

983137983138983148983141 983089 Level o process parameters

Symbol Factor level 983089 983090 983091

A NaOH concentration (M) 983089983088 983096 983089983090

B iO983090 particle size (nm) 983089983092 983090983089 983089983088983088

C Autoclave temperature (∘C) 983089983096983088 983090983088983088 983090983091983088

D Annealing temperature (∘

C) 983092983093983088 983093983088983088 983093983093983088

different particle sizes has been proposed in the past [983090983089ndash983090983095]Here triple iO

2 layer structure with small particle sizes is at

the bottom medium sizes in the middle and large particlesizes on top which are also investigated to improve the solarperormance o DSSCs

2 Experiments

Te 983090cm times 983089983093 cm 1047298uorine-doped SnO2

- (FO-) coatedglass electrodes (sheet resistance 983096

Ω

◻) were cleaned by

acetone isopropanol and deionized water sequentially In thehydrothermal procedure 983091 g iO

2 powders were placed into a

e1047298on lined autoclave o 983089983088983088 mL capacity Te autoclave was1047297lled with 983096 M 983089983088 M or 983089983090 M NaOH aqueous solution andsealed into a stainless steel tank and maintained at 983089983096983088∘C or983090983092 hrs It was cooled down naturally to room temperatureTe obtained sodium titanate was put into 983090983088983088 mL o 983089 NHCl aqueous solution at pH = 983090 and stirred or 983090983092 h TisHCl treatment was repeated many times in order to exchangeNa+ ions completely by H+ ions leading to the ormationo hydrogen titanate nanorods Ten these hydrogen titanatenanorods were washed with distilled water until the pHreached 983095 and 1047297ltered to obtain the precipitated hydrogen

titanate nanorods Tese nanorods were dehydrated andrecrystallized into the anatase iO

2 nanorods able 983089 shows

the our actors and three levels used in our experimentaccording to the aguchi method [983089983094ndash983090983088] I three levelswere assigned to each o these actors then conventional

method would require 9830914 or 983096983089 experiments to 1047297nd theoptimal condition Using the aguchi method we can reducethe number o experiments to nine Te orthogonal array o L983097 type [983089983095] is used and shown in able 983090 Tis designrequires nine experiments with our parameters at threelevels o each Te interactions o these our parameters wereneglected iO

2 solutions are prepared by mixing 983091 g o iO

2

powders 983089 mL o titanium tetraisopropoxide (IP) 983088983093 g

o Polyethylene glycol (PEG) and 983088983093 mL o triton X-983089983088983088 in983093983088 mL o isopropanol (IPA) Te mixture was then grindedand stirred by zirconia ball or 983096 hours It is known that theaddition o IP in the solution can reduce the surace crack and thePEG can make a porous thin 1047297lm afer annealing TeiO

2 thin 1047297lms were ormed by spin-coating iO

2 solutions

on FO-coated glass and annealed at 983093983088983088∘C or one hourTe coated iO

2 photo-electrodes were then immersed or

983090983092 hrs in a hydrous ethanol solution containing 3 times 10minus4 MN983095983089983097 dye Te liquid electrolyte consisted o 983089 M lithiumIodide (LiI) 983088983089 M Iodine (I

2) 983088983093 M 983092-tert-butyl pyridine

(BP) and 983088983094 M 983089983090-Dimethyl-983091-propylimidazolium iodide(DMPII) in acetonitrile Te cathode electrode was made o

0

1

2

3

4

5

6

NaOHconcentration particle size

Autoclave

temperature

Annealing

temperature

159

359

280

341

309

370

259

280

543

439

382

521

S N

A1 A2 A3 B1 B2 B3 C1 C2 C3 D1 D2 D3

TiO2

F983145983143983157983154983141 983089 Te actor effects on the 1038389 ratio

FO-coated glass which was urther coated with H2PtCl

6

precursor and annealed at 983092983093983088∘C or 983091983088 min Te cell wasabricated by applying a surlyn spacer which is a hot-melting1047297lm with a thickness o 983094983088 1103925m between two electrodes woFO-coated glasses were made with the surlyn heated at983089983088983088∘C Te electrolyte was injected into the space between theelectrodes by capillary action Finally these two FO-coated

glasses were sealed completely Te activearea o cells is 983089 cm2Te photocurrent-voltage (907317-) characteristic curves weremeasured using Keithley 983090983092983090983088 under AM983089983093G illumination

3 Results and DiscussionsNine different hydrothermal experiments were perormedusing the design parameter combinations shown in able 983090Tree specimens were abricated or each o the parametercombinations Te actor effects on the solar efficiency and1038389 ratio or each experiment are listed in able 983091 Tehigher solar efficiency is the indication o betterperormanceTereore the larger-is-better criterion was selected or thesolar efficiency to obtain the optimal solar perormanceTe ollowing 1038389 ratios or the larger-is-better case can becalculated [983089983094 983089983096]

1048616 10383891048617LB = minus10 logsum

1038389=1

19830801038389

9830812

(983089)

where (1038389)LB stands or the larger-is-better signal-to-noiseratio

1038389 is the individually measured solar efficiency and is

the number o solar cell samples measuredFigure 983089 shows theactor effects on the1038389 ratio Te larger slope means that theactor has a stronger effect on solar efficiency It indicates thatNaOH concentration (actor A) has a stronger effect on solarefficiency Te annealing temperature (actor D) is the nextmost signi1047297cant actor Te objective is to maximize the 1038389ratio Tis implies that one can obtain high solar efficiency by using the actor with higher 1038389 ratio It is clear romFigure 983089 that the highest 1038389 ratio values in each actor are



International Journal o Photoenergy 983091

983137983138983148983141 983090 aguchi L983097 orthogonal array

Order Factor

A NaOH concentration (M) B iO983090 particle size (nm) C Autoclave temperature (∘C) D Annealing temperature (∘C)

983089 983089983088 M 983089983092 nm 983089983096983088∘C 983092983093983088∘C

983090 983089983088 M 983090983089 nm 983090983088983088∘C 983093983088983088∘C

983091 983089983088 M 983089983088983088 nm 983090983091983088∘

C 983093983093983088∘

C983092 983096 M 983089983092 nm 983090983088983088∘C 983093983093983088∘C

983093 983096 M 983090983089 nm 983090983091983088∘C 983092983093983088∘C

983094 983096 M 983089983088983088 nm 983089983096983088∘C 983093983088983088∘C

983095 983089983090 M 983089983092 nm 983090983091983088∘C 983093983088983088∘C

983096 983089983090 M 983090983089 nm 983089983096983088∘C 983093983093983088∘C

983097 983089983090 M 983089983088983088 nm 983090983088983088∘C 983092983093983088∘C

983137983138983148983141 983091 Te actor effects on the solar efficiency and 1038389 ratio

FactorEfficiency () 1038389 ratio

A NaOH

concentration (M)

B iO983090 particle size

(nm)

C Autoclave

temperature (

∘

C)

D Annealing

temperature (

∘

C)983089 983089 983089 983089 983090983091983089 983095983090983095

983089 983090 983090 983090 983089983096983088 983093983089983089

983089 983091 983091 983091 983089983093983095 983091983097983090

983090 983089 983090 983091 983089983090983095 983090983088983096

983090 983090 983091 983089 983090983088983094 983094983090983096

983090 983091 983089 983090 983089983091983090 983090983092983089

983091 983089 983091 983090 983089983089983089 983088983097983089

983091 983090 983089 983091 983089983090983091 983089983096983088

983091 983091 983090 983089 983089983090983095 983090983088983096

983093983092983091 983092983091983097 983091983096983090 and 983093983090983089 which correspond to the actor A983089B983090 C983089 and D983089 respectively Tereore the best parameterso hydrothermal methods are (A983089) NaOH concentration o 983089983088 M (B983090) commercial iO

2 particle size o 983090983089 nm (C983089) the

temperature o 983089983096983088∘C and (D983089) the annealing temperature o 983092983093983088∘C Tus these best parameters were used to prepare ouriO

2 nanorods

Figures 983090(a) and 983090(b) show the surace morphology o iO

2 1047297lms prepared by commercial iO

2 particles and iO

2

nanorods which we prepared using hydrothermal methodsrespectively Clearly a particle-like surace in the 1047297lm isprepared using commercial particles versus a nanorod-

shape surace in the 1047297lm prepared by our iO2 nanorodsFrom atomic orce microscopy (AFM) measurement it isobserved that the mean roughness (sim983094983091nm) o the iO

2

thin 1047297lms prepared by the iO2

nanorods is larger than that(sim983092983089983093 nm) prepared by the commercial iO

2 particles Te

large surace roughness in iO2

nanorods is bene1047297cial ordye adsorption In addition a very pure anatase structureo iO

2 nanorods is obtained by the hydrothermal method

as shown in Figure 983091 Tere are no characteristic peaks o other impurity phases such as sodium titanium oxide orrutile iO

2 except pure anatase iO

2 nanorods Tis pure

anatase structure o iO2

is extremely important to achievehigh perormance or electrons transport and dye adsorption

in iO2-based dye-sensitized solar cells [983090983096 983090983097] Figure 983092

compares the 907317- characteristics o dye-sensitized solar cellprepared with hydrothermally grown iO

2 nanorods and the

DSSC prepared with commercial iO2

particles Te dye-sensitized solarcells prepared with the hydrothermally growniO

2 nanorods clearly exhibit highersolar efficiency than that

prepared with the commercial iO2

particles Tis is due tothe act that iO

2 nanorods have large surace area and pure

anatase structure which can absorb more dye and thereorebetter photoresponse

It is also noted that the size o iO2

nanorods syn-thesized by hydrothermal method depends on the initial

iO2 particle size Te nanorods are thin and long whensmall-size iO

2 particles (size sim983089983092 nm) are used however

the nanorods become thick and short when large-size iO2

particles are used (size sim983089983088983088 nm) as shown in Figures 983093(a)and 983093(b) One can control the shape o iO

2 nanorods

by suitably choosing the initial iO2

particle sizes used inthe hydrothermal process Next we will examine the effecto iO

2 thin 1047297lm thickness on the solar efficiency o the

abricated DSSCs In Figure 983094 the cross-section scanningelectron microscopy (SEM) images o different thickness o iO

2 thin 1047297lms are shown We can see that a nanorod-like

morphology is observed when 983090983089 nm iO2

powder is usedin the hydrothermal reaction Te optical absorption and




(a) (b)

F983145983143983157983154983141 983090 Surace morphology o iO2 thin 1047297lms prepared by (a) commercial particles and (b) hydrothermal method

20 25 30 35 40 45 50 55 60

R R

R R

AA

AA

A

I n t e n s i t y

( a u

)

A

A

R

2

hy21 nm

21 nm

F983145983143983157983154983141 983091 XRD spectra o iO2 thin 1047297lms prepared by hydrothermal method (red color) and commercial particle (blue color)

00 01 02 03 04 05 06 07 090800

05

10

15

20

25

30

35

40

45

50

hy21 nm21 nm

Efficiency

()

176

244

ff

062

062363

433

(V)

078

078

Workingarea

1 cm2

21 nm

hy21 nm

Voc

Voc (V)

J s c J sc

( m A c

m 2 )

(mAcm2

)

F983145983143983157983154983141 983092 Te 907317- curve o dye-sensitized solar cells with the iO2 prepared by hydrothermal method and commercial particle




(a) (b)

F983145983143983157983154983141 983093 Nanorod size dependence on the using o the particle size o (a) 983089983092 nm and (b) 983089983088983088 nm

351038389m 51038389m 951038389m

121038389m 151038389m

F983145983143983157983154983141 983094 Te cross-section scanning electron microscopy (SEM) images o iO2 thin 1047297lms with different thicknesses

907317- characteristic curve o dye-sensitized solar cells withdifferent iO

2 thicknesses are shown in Figures 983095(a) and 983095(b)

respectively Te optical absorption initially increases withincreasing iO

2 thickness and reaches a maximum at 983089983090 1103925m

For urther increase in the iO2

1047297lm thickness the lightabsorption begins to drop Te same behavior is observed inthe photocurrent as shown in Figure 983095(b) Te solar peror-mance parameters o DSSCs with different iO

2 thicknesses

are listed in able 983092 Te efficiencies o DSSCs with the iO2

thicknesses o983091983093983093 983097983093 983089983090and983089983093 1103925m are 983090983089983090 983090983092983092983090983094983091 983090983096983093and 983090983094983095 respectively Te DSSC with the iO

2 thicknesses

o 983089983090 1103925m exhibits the highest efficiency It is known thatdye in the 1047297lm will build up with increasing iO

2 thickness

and hence increase the photocurrent However thicker iO2

layers will result in a decrease in the transmittance o light

through these iO2 layers and thus reduce the incident light

absorbed by the dyes In addition the charge recombination

between electrons rom the excited dye to the conductionband o iO

2 and the I3minus ions in the electrolyte will become

more difficult in thicker iO2

layers Tus there exists anoptimal iO

2 thickness to achieve higher solar efficiency or

each particle size In this work the optimal iO2

thicknessis 983089983090 1103925m or particle size o 983090983089 nm used in the hydrothermalreaction

It is known that large-size iO2 particles have the advan-

tage o strong light scattering ability while small size iO2

particles have the advantages o large contact area and low contact resistance [983089983096ndash983090983092] In order to take the advantages o both the strong light scattering and the large contact arealow contact resistance we constructed a triple-layer iO

2 DSSC




983137983138983148983141 983092 Solar perormance parameters o DSSCs with different iO983090 thicknesses

Working area 983089 cm983090 oc (V) sc (mAcm983090) Fill actor Efficiency ()

983091983093 um 983088983095983097 983091983094983091 983088983094983090 983090983089983090

983093 um 983088983095983094 983092983095983091 983088983094983090 983090983092983092

983097983093 um 983088983095983095 983093983090983093 983088983094983092 983090983094983091

983089983090 um 983088983095983094 983093983096983097 983088983094983091 983090983096983093983089983093 um 983088983095983094 983093983093983096 983088983094983090 983090983094983095

400 500 600 700 800 9000

1

2

3

A b s o r b a n c e

( a u

)

Wavelength (nm)

351038389m51038389m

951038389m

121038389m

151038389m

(a)

00 01 02 03 04 05 06 07 080

1

2

3

4

5

6

7

J s c

( m A c m

2 )

Voc (V)

351038389m51038389m

951038389m

121038389m

151038389m

(b)

F983145983143983157983154983141 983095 (a) Light absorption and (b) 907317- curve o dye-sensitized solar cells with different iO2 thicknesses

983137983138983148983141 983093 Solar perormance parameters o DSSCs with differentparticle sizes on the top in triple iO983090 layers

Particle size (nm) oc (V) sc (mAcm983090) Fill

actorEfficiency

()

983093983088hy983090983089983097FO 983088983094983095 983096983096983093 983088983094983089 983091983094983090

983089983088983088hy983090983089983097FO 983088983095983093 983089983090983088983090 983088983094983090 983093983094983096

983090983088983088hy983090983089983097FO 983088983095983094 983089983092983091983090 983088983094983089 983094983093983092

with varying iO2

particle size Te structure o the triple-

layer iO2 DSSC is as ollows (1) a iO2 thin 1047297lm preparedwith 983097 nm iO

2 particles is on the bottom layer (983090) a iO

2

1047297lm prepared with hydrothermally grown iO2

nanorodsis placed on the middle layer (983091) on the top iO

2 1047297lms

are prepared with three different sizes o 983093983088 nm 983089983088983088 nmand 983090983088983088 nm iO

2 nanorods used or comparison Figure 983096(a)

shows the cross-sectional scanning electron microscopy (SEM) images o iO

2 thin 1047297lms with triple-layer structures

Te 907317- curves o dye-sensitized solar cells with triple-layerstructures are shown in Figure 983096(b) Te solar perormanceparameters o DSSCs with triple-layer structures are listed inable 983093 Te efficiencies o DSSCs with the scattering layerprepared by 983093983088 983089983088983088 and 983090983088983088 nm particles are 983091983094983090 983093983094983096

and 983094983093983092 respectively Te iO2

layers with larger particlesizes on the top layer exhibit higher solar efficiency than thatwith smaller particle sizes due to the strong back-scatteringeffect It is known that smaller particles o iO

2 layers have

large surace area and adsorb more dyes Hence it has low contact resistance and high photocurrent Te strong back-scattering light due to large particle size will also increasethe reabsorption in the small particle size o iO

2 layer Tis

smaller particle size on the bottom is bene1047297cial to recapturethe scattering light rom the top scattering layer Te largerparticle sizes o iO

2 layers on the top can enhance the back-

scattering light effectively and result in higher photocurrent

Tus the combination o larger particle sizes o iO2 on thetop and smaller particle sizes o iO

2 at the bottom will be

better or achieving higher solar efficiency

4 Conclusions

Te dye-sensitized solar cells with the iO2

prepared by the hydrothermal method have demonstrated good solarperormance A high surace roughness and pure anatasestructure are achieved by this method Te dye-sensitizedsolar cells with the iO

2 nanorods exhibit higher solar

efficiency than that with the commercial iO2

particles Teoptimal iO

2 thickness depends on the nanorod sizes o




(a)

00 01 02 03 04 05 06 07 080

2

4

6

8

10

12

14

16

50hy219FTO100hy219FTO

200hy219FTO

Voc (V)

J s c

( m A c m

2 )

(b)

F983145983143983157983154983141 983096 (a) Te cross-section scanning electron microscopy (SEM) images o iO

2 thin 1047297lms with triple layer structures (b) 907317-

curve o dye-sensitizedsolar cellswith triple layer structureso iO2

thin 1047297lms

iO2

layer or achieving the maximum efficiency Te iO2

nanorod size ormed through the hydrothermal method willdepend on the initial iO

2 particle size

Acknowledgment

Te authors want to thank the National Science Councilo aiwan aiwan or supporting this research under theContract no NSC 983089983088983088-983090983090983090983089-E-983089983096983090-983088983091983095

References

[983089] B OrsquoRegan and M Gratzel ldquoA low-cost high-efficiency solarcell based on dye-sensitized colloidal iO

2 1047297lmsrdquo Nature vol

983091983093983091 no 983094983091983092983094 pp 983095983091983095ndash983095983092983088 983089983097983097983089

[983090] M Gratzel ldquoConversion o sunlight to electric power by nanocrystalline dye-sensitized solar cellsrdquo Journal of Photo-chemistry and Photobiology A vol 983089983094983092 no 983089-983091 pp 983091ndash983089983092 983090983088983088983092

[983091] Q Zhang C S Dandeneau X Zhou and C Cao ldquoZnO nanos-tructures or dye-sensitized solar cellsrdquo Advanced Materials vol983090983089 no 983092983089 pp 983092983088983096983095ndash983092983089983088983096 983090983088983088983097

[983092] S Ito N Murakami P Comte et al ldquoFabrication o thin 1047297lmdye sensitized solar cells with solar to electric power conversionefficiency over 983089983088rdquo Tin Solid Films vol 983093983089983094 no 983089983092 pp 983092983094983089983091ndash983092983094983089983097 983090983088983088983096

[983093] D Kuang S Ito B Wenger et al ldquoHigh molar extinctioncoefficient heteroleptic ruthenium complexes or thin 1047297lm dye-sensitized solar cellsrdquo Journal of the American Chemical Society vol 983089983090983096 no 983089983090 pp 983092983089983092983094ndash983092983089983093983092 983090983088983088983094

[983094] A Yella H-W Lee H N sao et al ldquoPorphyrin-sensitizedsolar cells with cobalt (IIIII)-based redox electrolyte exceed 983089983090percent efficiencyrdquo Science vol 983091983091983092 no 983094983088983093983094 pp 983094983090983097ndash983094983091983092 983090983088983089983089

[983095] Q Zhang and G Cao ldquoNanostructured photoelectrodes ordye-sensitized solar cellsrdquo Nano oday vol 983094 no 983089 pp 983097983089ndash983089983088983097983090983088983089983089

[983096] M Wei Y Konishi H Zhou M Yanagida H Sugihara and HArakawa ldquoHighly efficient dye-sensitized solar cells composedo mesoporous titanium dioxiderdquo Journal of Materials Chem-istry vol 983089983094 no 983089983091 pp 983089983090983096983095ndash983089983090983097983091 983090983088983088983094

[983097] W-G Yang F-R Wan Q-W Chen J-J Li and D-S XuldquoControlling synthesis o well-crystallized mesoporous iO

2

microspheres with ultrahigh surace area or high-perormancedye-sensitized solar cellsrdquo Journal of Materials Chemistry vol983090983088 no 983089983092 pp 983090983096983095983088ndash983090983096983095983094 983090983088983089983088

[983089983088] DChenF Huang Y-B Cheng andR A Caruso ldquoMesoporousanatase iO

2 beads with high surace areas and controllable

pore sizes a superior candidate or high-perormance dye-sensitized solar cellsrdquo Advanced Materials vol 983090983089 no 983090983089 pp983090983090983088983094ndash983090983090983089983088 983090983088983088983097

[983089983089] Y J Kim M H Lee H J Kim et al ldquoFormation o highly effi-cient dye-sensitized solar cells by hierarchical pore generationwith nanoporous iO

2spheresrdquo Advanced Materials vol 983090983089 no

983091983094 pp 983091983094983089983096ndash983091983094983095983091 983090983088983088983097[983089983090] F Sauvage D Chen P Comte et al ldquoDye-sensitized solar cellsemploying a single 1047297lm o mesoporous iO

2 beads achieve

power conversion efficiencies over 983089983088rdquo ACS Nano vol 983092 no983096 pp 983092983092983090983088ndash983092983092983090983093 983090983088983089983088

[983089983091] A C Zaman C B Ustundag F Kaya and C Kaya ldquoSynthesisand electrophoretic deposition o hydrothermally synthesizedmultilayer iO

2 nanotubes on conductive 1047297ltersrdquo Materials

Letters vol 983094983094 no 983089 pp 983089983095983097ndash983089983096983089 983090983088983089983090

[983089983092] S K S Patel N S Gajbhiye and S K Date ldquoFerromagnetismo Mn-doped iO

2 nanorods synthesized by hydrothermal

methodrdquo Journal of Alloys and Compounds vol 983093983088983097 no 983089 ppS983092983090983095ndashS983092983091983088 983090983088983089983089

[983089983093] J S Chen and X W Lou ldquoAnatase iO2 nanosheet an idealhost

structure or ast and efficient lithium insertionextractionrdquoElectrochemistry Communications vol 983089983089 no 983089983090 pp 983090983091983091983090ndash983090983091983091983093983090983088983088983097

[983089983094] R H Lochner and J E Matar Design for Quality An Introduc-tion to the Best of aguchi and Western Methods of Statistical Experimental Design Chapman and Hall New York NY USA983089983097983097983088

[983089983095] P Sharma A Verma R K Sidhu and O P Pandey ldquoProcessparameterselection orstrontium errite sinteredmagnets usingaguchi L983097 orthogonal designrdquo Journal of Materials Processing echnology vol 983089983094983096 no 983089 pp 983089983092983095ndash983089983093983089 983090983088983088983093

[983089983096] G P Syrcos ldquoDie casting process optimization using aguchimethodsrdquo Journal of Materials Processing echnology vol 983089983091983093no 983089 pp 983094983096ndash983095983092 983090983088983088983091




[983089983097] S S Mehdi M Khorasani and A Jamshidi ldquoHydrothermalprocessing o hydroxyapatite nanoparticlesmdasha aguchi experi-mental design approachrdquo Journal of Crystal Growth vol 983091983094983089 pp983095983091ndash983096983092 983090983088983089983090

[983090983088] M Dargahi H Kazemian M Soltanieh M Hosseinpour andS Rohani ldquoHigh temperature synthesis o SAPO-983091983092 applyingan L983097 aguchi orthogonal design to investigate the effects o experimental parametersrdquo Powder echnology vol 983090983089983095 pp 983090983090983091ndash983090983091983088 983090983088983089983090

[983090983089] H P Wu C M Lan JY Hu et al ldquoHybridtitania photoanodeswith a nanostructured multi-layer con1047297guration or highly efficient dye-sensitized solar cellsrdquo Te Journal of Physical Chemistry Letters vol 983092 no 983097 pp 983089983093983095983088ndash983089983093983095983095 983090983088983089983091

[983090983090] J-Y Liao B-X Lei D-B Kuang and C-Y Su ldquori-unctionalhierarchical iO

2 spheres consisting o anatase nanorods and

nanoparticles or high efficiency dye-sensitized solar cellsrdquoEnergy and Environmental Science vol 983092 no 983089983088 pp 983092983088983095983097ndash983092983088983096983093983090983088983089983089

[983090983091] Z-S Wang H Kawauchi Kashima and H ArakawaldquoSigni1047297cant in1047298uence o iO

2 photoelectrode morphology on

the energy conversion efficiency o N983095983089983097 dye-sensitized solarcellrdquo Coordination Chemistry Reviews vol 983090983092983096 no 983089983091-983089983092 pp983089983091983096983089ndash983089983091983096983097 983090983088983088983092

[983090983092] K Yan Y Qiu W Chen M Zhang and S Yang ldquoA double lay-ered photoanode made o highly crystalline iO

2 nanooctahe-

dra and agglutinated mesoporous iO2

microspheres or highefficiency dye sensitized solar cellsrdquo Energy and Environmental Science vol 983092 no 983094 pp 983090983089983094983096ndash983090983089983095983094 983090983088983089983089

[983090983093] I G Yu Y J Kim H J Kim C Lee and W I Lee ldquoSize-dependent light-scattering effects o nanoporous iO

2 spheres

in dye-sensitized solar cellsrdquo Journalof MaterialsChemistry vol983090983089 no 983090 pp 983093983091983090ndash983093983091983096 983090983088983089983089

[983090983094] Y-C Park Y-J Chang B-G Kum et al ldquoSize-tunable meso-porous spherical iO

2 as a scattering overlayer in high-

perormance dye-sensitized solar cellsrdquo Journal of MaterialsChemistry vol 983090983089 no 983090983094 pp 983097983093983096983090ndash983097983093983096983094 983090983088983089983089

[983090983095] M-J Jeng Y-L Wung L-B Chang and L Chow ldquoParticle sizeeffects o iO

2 layers on the solar efficiency o dye-sensitized

solar cellsrdquo International Journal of Photoenergy vol 983090983088983089983091Article ID 983093983094983091983096983097983095 983097 pages 983090983088983089983091

[983090983096] N-G Park J Van De Lagemaat and A J Frank ldquoComparisono dye-sensitized rutile- and anatase-based iO

2 solar cellsrdquo

Journal of Physical Chemistry B vol 983089983088983092 no 983091983096 pp 983096983097983096983097ndash983096983097983097983092983090983088983088983088

[983090983097] C S Karthikeyan M Telakkat and M Willert-Porada ldquoDi-erent mesoporous titania 1047297lms or solid-state dye sensitisedsolar cellsrdquo Tin Solid Films vol 983093983089983089-983093983089983090 pp 983089983096983095ndash983089983097983092 983090983088983088983094



Submit your manuscripts at

httpwwwhindawicom




983137983138983148983141 983089 Level o process parameters

Symbol Factor level 983089 983090 983091

A NaOH concentration (M) 983089983088 983096 983089983090

B iO983090 particle size (nm) 983089983092 983090983089 983089983088983088

C Autoclave temperature (∘C) 983089983096983088 983090983088983088 983090983091983088

D Annealing temperature (∘

C) 983092983093983088 983093983088983088 983093983093983088

different particle sizes has been proposed in the past [983090983089ndash983090983095]Here triple iO

2 layer structure with small particle sizes is at

the bottom medium sizes in the middle and large particlesizes on top which are also investigated to improve the solarperormance o DSSCs

2 Experiments

Te 983090cm times 983089983093 cm 1047298uorine-doped SnO2

- (FO-) coatedglass electrodes (sheet resistance 983096

Ω

◻) were cleaned by

acetone isopropanol and deionized water sequentially In thehydrothermal procedure 983091 g iO

2 powders were placed into a

e1047298on lined autoclave o 983089983088983088 mL capacity Te autoclave was1047297lled with 983096 M 983089983088 M or 983089983090 M NaOH aqueous solution andsealed into a stainless steel tank and maintained at 983089983096983088∘C or983090983092 hrs It was cooled down naturally to room temperatureTe obtained sodium titanate was put into 983090983088983088 mL o 983089 NHCl aqueous solution at pH = 983090 and stirred or 983090983092 h TisHCl treatment was repeated many times in order to exchangeNa+ ions completely by H+ ions leading to the ormationo hydrogen titanate nanorods Ten these hydrogen titanatenanorods were washed with distilled water until the pHreached 983095 and 1047297ltered to obtain the precipitated hydrogen

titanate nanorods Tese nanorods were dehydrated andrecrystallized into the anatase iO

2 nanorods able 983089 shows

the our actors and three levels used in our experimentaccording to the aguchi method [983089983094ndash983090983088] I three levelswere assigned to each o these actors then conventional

method would require 9830914 or 983096983089 experiments to 1047297nd theoptimal condition Using the aguchi method we can reducethe number o experiments to nine Te orthogonal array o L983097 type [983089983095] is used and shown in able 983090 Tis designrequires nine experiments with our parameters at threelevels o each Te interactions o these our parameters wereneglected iO

2 solutions are prepared by mixing 983091 g o iO

2

powders 983089 mL o titanium tetraisopropoxide (IP) 983088983093 g

o Polyethylene glycol (PEG) and 983088983093 mL o triton X-983089983088983088 in983093983088 mL o isopropanol (IPA) Te mixture was then grindedand stirred by zirconia ball or 983096 hours It is known that theaddition o IP in the solution can reduce the surace crack and thePEG can make a porous thin 1047297lm afer annealing TeiO

2 thin 1047297lms were ormed by spin-coating iO

2 solutions

on FO-coated glass and annealed at 983093983088983088∘C or one hourTe coated iO

2 photo-electrodes were then immersed or

983090983092 hrs in a hydrous ethanol solution containing 3 times 10minus4 MN983095983089983097 dye Te liquid electrolyte consisted o 983089 M lithiumIodide (LiI) 983088983089 M Iodine (I

2) 983088983093 M 983092-tert-butyl pyridine

(BP) and 983088983094 M 983089983090-Dimethyl-983091-propylimidazolium iodide(DMPII) in acetonitrile Te cathode electrode was made o

0

1

2

3

4

5

6

NaOHconcentration particle size

Autoclave

temperature

Annealing

temperature

159

359

280

341

309

370

259

280

543

439

382

521

S N

A1 A2 A3 B1 B2 B3 C1 C2 C3 D1 D2 D3

TiO2

F983145983143983157983154983141 983089 Te actor effects on the 1038389 ratio

FO-coated glass which was urther coated with H2PtCl

6

precursor and annealed at 983092983093983088∘C or 983091983088 min Te cell wasabricated by applying a surlyn spacer which is a hot-melting1047297lm with a thickness o 983094983088 1103925m between two electrodes woFO-coated glasses were made with the surlyn heated at983089983088983088∘C Te electrolyte was injected into the space between theelectrodes by capillary action Finally these two FO-coated

glasses were sealed completely Te activearea o cells is 983089 cm2Te photocurrent-voltage (907317-) characteristic curves weremeasured using Keithley 983090983092983090983088 under AM983089983093G illumination

3 Results and DiscussionsNine different hydrothermal experiments were perormedusing the design parameter combinations shown in able 983090Tree specimens were abricated or each o the parametercombinations Te actor effects on the solar efficiency and1038389 ratio or each experiment are listed in able 983091 Tehigher solar efficiency is the indication o betterperormanceTereore the larger-is-better criterion was selected or thesolar efficiency to obtain the optimal solar perormanceTe ollowing 1038389 ratios or the larger-is-better case can becalculated [983089983094 983089983096]

1048616 10383891048617LB = minus10 logsum

1038389=1

19830801038389

9830812

(983089)

where (1038389)LB stands or the larger-is-better signal-to-noiseratio

1038389 is the individually measured solar efficiency and is

the number o solar cell samples measuredFigure 983089 shows theactor effects on the1038389 ratio Te larger slope means that theactor has a stronger effect on solar efficiency It indicates thatNaOH concentration (actor A) has a stronger effect on solarefficiency Te annealing temperature (actor D) is the nextmost signi1047297cant actor Te objective is to maximize the 1038389ratio Tis implies that one can obtain high solar efficiency by using the actor with higher 1038389 ratio It is clear romFigure 983089 that the highest 1038389 ratio values in each actor are





Order Factor


983089 983089983088 M 983089983092 nm 983089983096983088∘C 983092983093983088∘C

983090 983089983088 M 983090983089 nm 983090983088983088∘C 983093983088983088∘C

983091 983089983088 M 983089983088983088 nm 983090983091983088∘

C 983093983093983088∘

C983092 983096 M 983089983092 nm 983090983088983088∘C 983093983093983088∘C

983093 983096 M 983090983089 nm 983090983091983088∘C 983092983093983088∘C

983094 983096 M 983089983088983088 nm 983089983096983088∘C 983093983088983088∘C

983095 983089983090 M 983089983092 nm 983090983091983088∘C 983093983088983088∘C

983096 983089983090 M 983090983089 nm 983089983096983088∘C 983093983093983088∘C

983097 983089983090 M 983089983088983088 nm 983090983088983088∘C 983092983093983088∘C



A NaOH

concentration (M)


(nm)

C Autoclave

temperature (

∘

C)

D Annealing

temperature (

∘

C)983089 983089 983089 983089 983090983091983089 983095983090983095

983089 983090 983090 983090 983089983096983088 983093983089983089

983089 983091 983091 983091 983089983093983095 983091983097983090

983090 983089 983090 983091 983089983090983095 983090983088983096

983090 983090 983091 983089 983090983088983094 983094983090983096

983090 983091 983089 983090 983089983091983090 983090983092983089

983091 983089 983091 983090 983089983089983089 983088983097983089

983091 983090 983089 983091 983089983090983091 983089983096983088

983091 983091 983090 983089 983089983090983095 983090983088983096




2 nanorods



2 particles and iO

2



2



2 particles Te






2 nanorods Tis pure





2 nanorods and the














2 nanorods











(a) (b)


20 25 30 35 40 45 50 55 60

R R

R R

AA

AA

A

I n t e n s i t y

( a u

)

A

A

R

2

hy21 nm

21 nm


00 01 02 03 04 05 06 07 090800

05

10

15

20

25

30

35

40

45

50

hy21 nm21 nm

Efficiency

()

176

244

ff

062

062363

433

(V)

078

078

Workingarea

1 cm2

21 nm

hy21 nm

Voc

Voc (V)

J s c J sc

( m A c

m 2 )

(mAcm2

)





(a) (b)


351038389m 51038389m 951038389m

121038389m 151038389m








2 thicknesses



2 thicknesses


2 thickness















2 DSSC






983091983093 um 983088983095983097 983091983094983091 983088983094983090 983090983089983090

983093 um 983088983095983094 983092983095983091 983088983094983090 983090983092983092

983097983093 um 983088983095983095 983093983090983093 983088983094983092 983090983094983091

983089983090 um 983088983095983094 983093983096983097 983088983094983091 983090983096983093983089983093 um 983088983095983094 983093983093983096 983088983094983090 983090983094983095

400 500 600 700 800 9000

1

2

3

A b s o r b a n c e

( a u

)

Wavelength (nm)

351038389m51038389m

951038389m

121038389m

151038389m

(a)

00 01 02 03 04 05 06 07 080

1

2

3

4

5

6

7

J s c

( m A c m

2 )

Voc (V)

351038389m51038389m

951038389m

121038389m

151038389m

(b)




actorEfficiency

()

983093983088hy983090983089983097FO 983088983094983095 983096983096983093 983088983094983089 983091983094983090

983089983088983088hy983090983089983097FO 983088983095983093 983089983090983088983090 983088983094983090 983093983094983096

983090983088983088hy983090983089983097FO 983088983095983094 983089983092983091983090 983088983094983089 983094983093983092

with varying iO2




2



2 1047297lms








2 layers have


2 layer Tis







4 Conclusions










(a)

00 01 02 03 04 05 06 07 080

2

4

6

8

10

12

14

16


200hy219FTO

Voc (V)

J s c

( m A c m

2 )

(b)




thin 1047297lms

iO2



2 particle size

Acknowledgment


References



983091983093983091 no 983094983091983092983094 pp 983095983091983095ndash983095983092983088 983089983097983097983089









2








2 beads achieve


























2 nanooctahe-




2 spheres









2 solar cellsrdquo






httpwwwhindawicom





Order Factor


983089 983089983088 M 983089983092 nm 983089983096983088∘C 983092983093983088∘C

983090 983089983088 M 983090983089 nm 983090983088983088∘C 983093983088983088∘C

983091 983089983088 M 983089983088983088 nm 983090983091983088∘

C 983093983093983088∘

C983092 983096 M 983089983092 nm 983090983088983088∘C 983093983093983088∘C

983093 983096 M 983090983089 nm 983090983091983088∘C 983092983093983088∘C

983094 983096 M 983089983088983088 nm 983089983096983088∘C 983093983088983088∘C

983095 983089983090 M 983089983092 nm 983090983091983088∘C 983093983088983088∘C

983096 983089983090 M 983090983089 nm 983089983096983088∘C 983093983093983088∘C

983097 983089983090 M 983089983088983088 nm 983090983088983088∘C 983092983093983088∘C



A NaOH

concentration (M)


(nm)

C Autoclave

temperature (

∘

C)

D Annealing

temperature (

∘

C)983089 983089 983089 983089 983090983091983089 983095983090983095

983089 983090 983090 983090 983089983096983088 983093983089983089

983089 983091 983091 983091 983089983093983095 983091983097983090

983090 983089 983090 983091 983089983090983095 983090983088983096

983090 983090 983091 983089 983090983088983094 983094983090983096

983090 983091 983089 983090 983089983091983090 983090983092983089

983091 983089 983091 983090 983089983089983089 983088983097983089

983091 983090 983089 983091 983089983090983091 983089983096983088

983091 983091 983090 983089 983089983090983095 983090983088983096




2 nanorods



2 particles and iO

2



2



2 particles Te






2 nanorods Tis pure





2 nanorods and the














2 nanorods











(a) (b)


20 25 30 35 40 45 50 55 60

R R

R R

AA

AA

A

I n t e n s i t y

( a u

)

A

A

R

2

hy21 nm

21 nm


00 01 02 03 04 05 06 07 090800

05

10

15

20

25

30

35

40

45

50

hy21 nm21 nm

Efficiency

()

176

244

ff

062

062363

433

(V)

078

078

Workingarea

1 cm2

21 nm

hy21 nm

Voc

Voc (V)

J s c J sc

( m A c

m 2 )

(mAcm2

)





(a) (b)


351038389m 51038389m 951038389m

121038389m 151038389m








2 thicknesses



2 thicknesses


2 thickness















2 DSSC






983091983093 um 983088983095983097 983091983094983091 983088983094983090 983090983089983090

983093 um 983088983095983094 983092983095983091 983088983094983090 983090983092983092

983097983093 um 983088983095983095 983093983090983093 983088983094983092 983090983094983091

983089983090 um 983088983095983094 983093983096983097 983088983094983091 983090983096983093983089983093 um 983088983095983094 983093983093983096 983088983094983090 983090983094983095

400 500 600 700 800 9000

1

2

3

A b s o r b a n c e

( a u

)

Wavelength (nm)

351038389m51038389m

951038389m

121038389m

151038389m

(a)

00 01 02 03 04 05 06 07 080

1

2

3

4

5

6

7

J s c

( m A c m

2 )

Voc (V)

351038389m51038389m

951038389m

121038389m

151038389m

(b)




actorEfficiency

()

983093983088hy983090983089983097FO 983088983094983095 983096983096983093 983088983094983089 983091983094983090

983089983088983088hy983090983089983097FO 983088983095983093 983089983090983088983090 983088983094983090 983093983094983096

983090983088983088hy983090983089983097FO 983088983095983094 983089983092983091983090 983088983094983089 983094983093983092

with varying iO2




2



2 1047297lms








2 layers have


2 layer Tis







4 Conclusions










(a)

00 01 02 03 04 05 06 07 080

2

4

6

8

10

12

14

16


200hy219FTO

Voc (V)

J s c

( m A c m

2 )

(b)




thin 1047297lms

iO2



2 particle size

Acknowledgment


References



983091983093983091 no 983094983091983092983094 pp 983095983091983095ndash983095983092983088 983089983097983097983089









2








2 beads achieve


























2 nanooctahe-




2 spheres









2 solar cellsrdquo






httpwwwhindawicom




(a) (b)


20 25 30 35 40 45 50 55 60

R R

R R

AA

AA

A

I n t e n s i t y

( a u

)

A

A

R

2

hy21 nm

21 nm


00 01 02 03 04 05 06 07 090800

05

10

15

20

25

30

35

40

45

50

hy21 nm21 nm

Efficiency

()

176

244

ff

062

062363

433

(V)

078

078

Workingarea

1 cm2

21 nm

hy21 nm

Voc

Voc (V)

J s c J sc

( m A c

m 2 )

(mAcm2

)





(a) (b)


351038389m 51038389m 951038389m

121038389m 151038389m








2 thicknesses



2 thicknesses


2 thickness















2 DSSC






983091983093 um 983088983095983097 983091983094983091 983088983094983090 983090983089983090

983093 um 983088983095983094 983092983095983091 983088983094983090 983090983092983092

983097983093 um 983088983095983095 983093983090983093 983088983094983092 983090983094983091

983089983090 um 983088983095983094 983093983096983097 983088983094983091 983090983096983093983089983093 um 983088983095983094 983093983093983096 983088983094983090 983090983094983095

400 500 600 700 800 9000

1

2

3

A b s o r b a n c e

( a u

)

Wavelength (nm)

351038389m51038389m

951038389m

121038389m

151038389m

(a)

00 01 02 03 04 05 06 07 080

1

2

3

4

5

6

7

J s c

( m A c m

2 )

Voc (V)

351038389m51038389m

951038389m

121038389m

151038389m

(b)




actorEfficiency

()

983093983088hy983090983089983097FO 983088983094983095 983096983096983093 983088983094983089 983091983094983090

983089983088983088hy983090983089983097FO 983088983095983093 983089983090983088983090 983088983094983090 983093983094983096

983090983088983088hy983090983089983097FO 983088983095983094 983089983092983091983090 983088983094983089 983094983093983092

with varying iO2




2



2 1047297lms








2 layers have


2 layer Tis







4 Conclusions










(a)

00 01 02 03 04 05 06 07 080

2

4

6

8

10

12

14

16


200hy219FTO

Voc (V)

J s c

( m A c m

2 )

(b)




thin 1047297lms

iO2



2 particle size

Acknowledgment


References



983091983093983091 no 983094983091983092983094 pp 983095983091983095ndash983095983092983088 983089983097983097983089









2








2 beads achieve


























2 nanooctahe-




2 spheres









2 solar cellsrdquo






httpwwwhindawicom




(a) (b)


351038389m 51038389m 951038389m

121038389m 151038389m








2 thicknesses



2 thicknesses


2 thickness















2 DSSC






983091983093 um 983088983095983097 983091983094983091 983088983094983090 983090983089983090

983093 um 983088983095983094 983092983095983091 983088983094983090 983090983092983092

983097983093 um 983088983095983095 983093983090983093 983088983094983092 983090983094983091

983089983090 um 983088983095983094 983093983096983097 983088983094983091 983090983096983093983089983093 um 983088983095983094 983093983093983096 983088983094983090 983090983094983095

400 500 600 700 800 9000

1

2

3

A b s o r b a n c e

( a u

)

Wavelength (nm)

351038389m51038389m

951038389m

121038389m

151038389m

(a)

00 01 02 03 04 05 06 07 080

1

2

3

4

5

6

7

J s c

( m A c m

2 )

Voc (V)

351038389m51038389m

951038389m

121038389m

151038389m

(b)




actorEfficiency

()

983093983088hy983090983089983097FO 983088983094983095 983096983096983093 983088983094983089 983091983094983090

983089983088983088hy983090983089983097FO 983088983095983093 983089983090983088983090 983088983094983090 983093983094983096

983090983088983088hy983090983089983097FO 983088983095983094 983089983092983091983090 983088983094983089 983094983093983092

with varying iO2




2



2 1047297lms








2 layers have


2 layer Tis







4 Conclusions










(a)

00 01 02 03 04 05 06 07 080

2

4

6

8

10

12

14

16


200hy219FTO

Voc (V)

J s c

( m A c m

2 )

(b)




thin 1047297lms

iO2



2 particle size

Acknowledgment


References



983091983093983091 no 983094983091983092983094 pp 983095983091983095ndash983095983092983088 983089983097983097983089









2








2 beads achieve


























2 nanooctahe-




2 spheres









2 solar cellsrdquo






httpwwwhindawicom






983091983093 um 983088983095983097 983091983094983091 983088983094983090 983090983089983090

983093 um 983088983095983094 983092983095983091 983088983094983090 983090983092983092

983097983093 um 983088983095983095 983093983090983093 983088983094983092 983090983094983091

983089983090 um 983088983095983094 983093983096983097 983088983094983091 983090983096983093983089983093 um 983088983095983094 983093983093983096 983088983094983090 983090983094983095

400 500 600 700 800 9000

1

2

3

A b s o r b a n c e

( a u

)

Wavelength (nm)

351038389m51038389m

951038389m

121038389m

151038389m

(a)

00 01 02 03 04 05 06 07 080

1

2

3

4

5

6

7

J s c

( m A c m

2 )

Voc (V)

351038389m51038389m

951038389m

121038389m

151038389m

(b)




actorEfficiency

()

983093983088hy983090983089983097FO 983088983094983095 983096983096983093 983088983094983089 983091983094983090

983089983088983088hy983090983089983097FO 983088983095983093 983089983090983088983090 983088983094983090 983093983094983096

983090983088983088hy983090983089983097FO 983088983095983094 983089983092983091983090 983088983094983089 983094983093983092

with varying iO2




2



2 1047297lms








2 layers have


2 layer Tis







4 Conclusions










(a)

00 01 02 03 04 05 06 07 080

2

4

6

8

10

12

14

16


200hy219FTO

Voc (V)

J s c

( m A c m

2 )

(b)




thin 1047297lms

iO2



2 particle size

Acknowledgment


References



983091983093983091 no 983094983091983092983094 pp 983095983091983095ndash983095983092983088 983089983097983097983089









2








2 beads achieve


























2 nanooctahe-




2 spheres









2 solar cellsrdquo






httpwwwhindawicom




(a)

00 01 02 03 04 05 06 07 080

2

4

6

8

10

12

14

16


200hy219FTO

Voc (V)

J s c

( m A c m

2 )

(b)




thin 1047297lms

iO2



2 particle size

Acknowledgment


References



983091983093983091 no 983094983091983092983094 pp 983095983091983095ndash983095983092983088 983089983097983097983089









2








2 beads achieve


























2 nanooctahe-




2 spheres









2 solar cellsrdquo






httpwwwhindawicom














2 nanooctahe-




2 spheres









2 solar cellsrdquo






httpwwwhindawicom




httpwwwhindawicom

cross section sem

Documents