Please wait a minute...

Frontiers of Optoelectronics

Front Optoelec Chin    2011, Vol. 4 Issue (1) : 59-64     DOI: 10.1007/s12200-011-0205-2
RESEARCH ARTICLE |
Dependence of porosity, charge recombination kinetics and photovoltaic performance on annealing condition of TiO2 films
Chang-Ryul LEE, Hui-Seon KIM, Nam-Gyu PARK()
School of Chemical Engineering, Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea
Download: PDF(227 KB)   HTML
Export: BibTeX | EndNote | Reference Manager | ProCite | RefWorks
Abstract

Effect of annealing temperature, time of nanocrystalline TiO2 film on porosity, electron transport/recombination and photovoltaic performance on dye-sensitized solar cell (DSSC) had been investigated in this article. Photocurrent density was slightly higher as annealing at 550°C compared to those of annealing at 450°C and 500°C under the given annealing time of 60?min, which was correlated with the amount of adsorbed dye. Thermogravimetric analysis showed there was a more weight loss between 500°C and 550°C, which revealed there were more sites for dye adsorption. Given the annealing temperature of 550°C, as annealing time varied from 60 to 90 and 120 min, results showed that the average size of pore and surface area decreased with longer annealing time, which deteriorated photocurrent density due to less dye loading. Electron diffusion rate remained almost unchanged regardless of annealing condition. However, electron recombination was influenced by annealing condition, it became slower with the increase of the annealing temperature under the given annealing time. In the contray, the electron recombination developed faster for the longer annealing time at a given annealing temperature. These results suggested that heat treatment of TiO2 film at 550°C for 60 min in air would be the optimal annealing condition to achieve high efficiency DSSC.

Keywords dye-sensitized solar cell (DSSC)      annealing conditions      surface area      porosity      electron life time     
Corresponding Authors: PARK Nam-Gyu,Email:npark@skku.edu   
Issue Date: 05 March 2011
 Cite this article:   
Chang-Ryul LEE,Hui-Seon KIM,Nam-Gyu PARK. Dependence of porosity, charge recombination kinetics and photovoltaic performance on annealing condition of TiO2 films[J]. Front Optoelec Chin, 2011, 4(1): 59-64.
 URL:  
http://journal.hep.com.cn/foe/EN/10.1007/s12200-011-0205-2
http://journal.hep.com.cn/foe/EN/Y2011/V4/I1/59
Service
E-mail this article
E-mail Alert
RSS
Articles by authors
Chang-Ryul LEE
Hui-Seon KIM
Nam-Gyu PARK
Fig.1  Effect of annealing temperature on short-circuit photocurrent density () and amount of adsorbed dye
Fig.1  Effect of annealing temperature on short-circuit photocurrent density () and amount of adsorbed dye
annealing temperatureJSC/(mA·cm-2)VOC/VFF/%η/%amount of adsorbeddye/(10-8 mol·cm-2)film thickness/μm
450°C12.27±0.20.828±0.010.74±0.0067.50±0.15.6010.38
500°C12.07±0.20.832±0.010.74±0.0047.43±0.15.3110.32
550°C12.53±0.20.830±0.010.74±0.0057.6±0.16.3410.45
Tab.1  Short-circuit photocurrent density (), open-circuit voltage (), fill factor (), conversion efficiency () and amount of adsorbed dye for TiO films annealed at different temperatures. Annealing temperature was varied at fixed time of 60 min. Measurements were performed under AM 1.5 G one sun light intensity (100 mW·cm) and cell was covered with mask having aperture during measurement.
Fig.2  Temperature-dependent weight loss of TiO paste between 400°C and 600°C (thermal gravimetric analysis (TGA) curve in entire measured temperature range, and data were collected under N atmosphere at a rate of 5°C/min)
Fig.2  Temperature-dependent weight loss of TiO paste between 400°C and 600°C (thermal gravimetric analysis (TGA) curve in entire measured temperature range, and data were collected under N atmosphere at a rate of 5°C/min)
Fig.3  (a) Photocurrent-voltage curves; (b) IPCE spectra of dye-sensitized solar cells with different annealing times of 60, 90, and 120 min at fixed temperature of 550°C
Fig.3  (a) Photocurrent-voltage curves; (b) IPCE spectra of dye-sensitized solar cells with different annealing times of 60, 90, and 120 min at fixed temperature of 550°C
annealing timeJSC /(mA·cm-2)VOC/VFFη/%amount of adsorbed dye/(10-8 mol·cm-2)film thickness/ μmsurface area/ (g·m-2)
60 min12.53±0.20.830±0.0173.37±0.57.67±0.16.3410.4065.62
90 min11.55±0.30.836±0.0172.95±0.57.05±0.15.8710.2247.99
120 min11.63±0.10.824±0.0171.70±0.96.83±0.14.3910.3744.70
Tab.2  , , , , amount of adsorbed dye and surface area for TiO films with different annealing times. Annealing time was varied at fixed temperature of 550°C. Measurements were performed under AM 1.5 G sun light intensity (100 mW·cm) and cell was covered with mask having aperture during measurement.
Fig.4  Results of surface area measurement. (a) Nitrogen adsorption-desorption hysteresis loops; (b) pore distribution for TiO films with different annealing time
Fig.4  Results of surface area measurement. (a) Nitrogen adsorption-desorption hysteresis loops; (b) pore distribution for TiO films with different annealing time
Fig.5  SEM of TiO nanoparticles with different annealing time at fixed annealing temperature of 550°C. (a) 60 min; (b) 120 min
Fig.5  SEM of TiO nanoparticles with different annealing time at fixed annealing temperature of 550°C. (a) 60 min; (b) 120 min
Fig.6  Effect of (a) annealing temperature and; (b) annealing time on time constants for recombination
Fig.6  Effect of (a) annealing temperature and; (b) annealing time on time constants for recombination
1 O’Regan B, Gr?tzel M. A low-cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films. Nature , 1991, 353(6346): 737–740
doi: 10.1038/353737a0
2 Gr?tzel M. Dye-sensitized solar cells. Journal of Photochemistry and Photobiology C, Photochemistry Reviews , 2003, 4(2): 145–153
doi: 10.1016/S1389-5567(03)00026-1
3 Gr?tzel M. Conversion of sunlight to electric power by nanocrystalline dye-sensitized solar cells. Journal of Photochemistry and Photobiology A Chemistry , 2004, 164(1-3): 3–14
doi: 10.1016/j.jphotochem.2004.02.023
4 Lee K T, Park S W, Ko M J, Kim K, Park N G. Selective positioning of organic dyes in a mesoporous inorganic oxide film. Nature Materials , 2009, 8(8): 665–671
doi: 10.1038/nmat2475 pmid:19561600
5 Opara K U, Berginc M, Hocevar M, Topic M. Unique TiO2 paste for high efficiency dye-sensitized solar cells. Solar Energy Materials and Solar Cells , 2009, 93(3): 379–381
doi: 10.1016/j.solmat.2008.11.012
6 Kavan L, Gr?tzel M, Rathousky J, Zukal A J. Nanocrystalline TiO2 (anatase) electrodes: Surface morphology, adsorption, and electrochemical properties. Journal of the Electrochemical Society , 1996, 143(2): 394–400
doi: 10.1149/1.1836455
7 Park N G, van de Lagemaat J, Frank A J. comparison of dye-sensitized rutile-and anatase-based TiO2 solar cells. Journal of Physical Chemistry B , 2000, 104(38): 8989–8994
doi: 10.1021/jp994365l
8 Adachi M, Jiu J, Isoda S. Synthesis of morphology-controlled titania nanocrystals and application for dye-sensitized solar cells. Current Nanoscience , 2007, 3(4): 285–295
doi: 10.2174/157341307782418577
9 Nakade S, Saito Y, Kubo W, Kitamura T, Wada Y, Yanagida S. Influence of TiO2 nanoparticle size on electron diffusion and recombination in dye-sensitized TiO2 solar cells. Journal of Physical Chemistry B , 2003, 107(33): 8607–8611
doi: 10.1021/jp034773w
10 Zhu K, Kopidakis N, Neale N R, van de Lagemaat J, Frank A J. Influence of surface area on charge transport and recombination in dye-sensitized TiO2 solar cells. Journal of Physical Chemistry B , 2006, 110(50): 25174–25180
doi: 10.1021/jp065284+ pmid:17165961
11 Lee K M, Suryanarayanan V, Ho K C. A study on the electron transport properties of TiO2 electrodes in dye-sensitized solar cells. Solar Energy Materials and Solar Cells , 2007, 91(15-16): 1416–1420
doi: 10.1016/j.solmat.2007.03.007
12 Centi G, Perathoner S. The role of nanostructure in improving the performance of electrodes for energy storage and conversion. European Journal of Inorganic Chemistry , 2009, 2009(26): 3851–3878
doi: 10.1002/ejic.200900275
13 Cass M J, Qiu F L, Walker A B, Fisher A C, Peter L M. Influence of grain morphology on electron transport in dye sensitized nanocrystalline solar cells. Journal of Physical Chemistry B , 2003, 107(1): 113–119
doi: 10.1021/jp026798l
14 van de Lagemaat J, Benkstein K D, Frank A J. Relation between particle coordination number and porosity in nanoparticle films: Implications to dye-sensitized solar cells. Journal of Physical Chemistry B , 2001, 105(50): 12433–12436
doi: 10.1021/jp013369z
15 Aduda B O, Ravirajan P, Choy K L, Nelson J. Effect of morphology on electron drift mobility in porous TiO2. International Journal of Photoenergy , 2004, 6(3): 141–147
doi: 10.1155/S1110662X04000170
16 Nakade S, Matsuda M, Kambe S, Saito Y, Kitamura T, Sakata T, Wada Y, Mori H, Yanagida S. Dependence of TiO2 nanoparticle preparation methods and annealing temperature on the efficiency of dye-sensitized solar cells. Journal of Physical Chemistry B , 2002, 106(39): 10004–10010
doi: 10.1021/jp020051d
17 Zhao D, Peng T Y, Lu S L, Cai P, Jiang P, Bian Z Q. Effect of annealing temperature on the phothelectrochemical properties of dye-sensitized solar cells made with mesoporous TiO2 nanoparticles. Journal of Physical Chemistry C , 2008, 112(22): 8486–8494
doi: 10.1021/jp800127x
18 Koo H J, Park J, Yoo B, Yoo K, Kim K, Park N G. Size-dependent scattering efficiency in dye-sensitized solar cell. Inorganica Chimica Acta , 2008, 361(3): 677–683
doi: 10.1016/j.ica.2007.05.017
19 Koide N, Han L. Measuring methods of cell performance of dye-sensitized solar cells. Review of Scientific Instruments , 2004, 75(9): 2828–2831
doi: 10.1063/1.1784556
20 Ito S, Nazeeruddin Md K, Liska P, Comte P, Charvet R, Pechy P, Jirousek M, Kay A, Zakeeruddin S M, Gr?tzel M. Photovoltaic characterization of dye-sensitized solar cells: effect of device masking on conversion efficiency. Progress in Photovoltaics: Research and Applications , 2006, 14(7): 589–601
doi: 10.1002/pip.683
21 Park J, Koo H J, Yoo B, Yoo K, Kim K, Choi W, Park N G. On the I-V measurement of dye-sensitized solar cell: Effect of cell geometry on photovoltaic parameters. Solar Energy Materials and Solar Cells , 2007, 91(18): 1749–1754
doi: 10.1016/j.solmat.2007.06.002
22 Mori S, Sunahara K, Fukai Y, Kanzaki T, Wada Y, Yanagida S. Electron transport and recombination in dye-sensitized TiO2 solar cells fabricated without sintering process. Journal of Physical Chemistry C , 2008, 112(51): 20505–20509
doi: 10.1021/jp8065629
Related articles from Frontiers Journals
[1] Cunxi CHENG, Jihuai WU, Yaoming XIAO, Yuan CHEN, Haijun YU, Ziying TANG, Jianming LIN, Miaoliang HUANG. Preparation of titanium dioxide-double-walled carbon nanotubes and its application in flexible dye-sensitized solar cells[J]. Front Optoelec, 2012, 5(2): 224-230.
[2] Gentian YUE, Jihuai WU, Jianming LIN, Miaoliang HUANG, Ying YAO, Leqing FAN, Yaoming XIAO. Application of Poly (3, 4-ethylenedioxythiophene): polystyrenesulfonate counter electrode in polymer heterojunction dye-sensitized solar cells[J]. Front Optoelec Chin, 2011, 4(4): 369-377.
[3] Quanyou FENG, Hong WANG, Gang ZHOU, Zhong-Sheng WANG. Effect of deoxycholic acid on performance of dye-sensitized solar cell based on black dye[J]. Front Optoelec Chin, 2011, 4(1): 80-86.
[4] Shuangying XU, Linhua HU, Jiang SHENG, Dongxing KOU, Huajun TIAN, Songyuan DAI. Electron transportation and optical properties of micro-structure TiO2 films: applied in dye-sensitized solar cells[J]. Front Optoelec Chin, 2011, 4(1): 72-79.
[5] Minghui DENG, Shuqing HUANG, Zhexun YU, Dongmei LI, Yanhong LUO, Yubai BAI, Qingbo MENG. Enhanced electron injection/transportation by surface states increment in mesoporous TiO2 dye-sensitized solar cells[J]. Front Optoelec Chin, 2011, 4(1): 65-71.
[6] Hong LIN, Feng HAO, Jianbao LI. Electrolyte-dependent photovoltaic responses in dye-sensitized solar cells[J]. Front Optoelec Chin, 2011, 4(1): 45-52.
[7] Wei CHEN, Shihe YANG. Dye-sensitized solar cells based on ZnO nanotetrapods[J]. Front Optoelec Chin, 2011, 4(1): 24-44.
[8] Qingqing MIAO, Mingxing WU, Wei GUO, Tingli MA. Studies of high-efficient and low-cost dye-sensitized solar cells[J]. Front Optoelec Chin, 2011, 4(1): 103-107.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed