CdS_xSe_y/TiO₂ Solar Cell Prepared with Sintered Mixture Deposition

Daniel Ogermann, Thorsten Wilke, Karl Kleinermanns

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Institute of Physical Chemistry, Heinrich-Heine-University, Duesseldorf, Germany.

DOI: 10.4236/ojpc.2012.21007                

Abstract

Gr?tzel cells were prepared by using CdSe- and CdSxSey-nanoparticles as sensitizer. The quantum dots were incorporated in various sizes and concentrations in a TiO2 nanoparticle layer by a simple mixing procedure. The advantage of this method compared to anchoring of nanoparticles to TiO₂ by linker molecules or chemical bath deposition is that we are able to control the ratio between TiO₂ and CdSe or CdS_xSe_y more precisely and over a larger range of concentrations. TiO₂ solar cells sensitized by this technique achieved photon-to-current conversion efficiencies (IPCE) of ~40% in the range of 300 - 500 nm with a maximum IPCE of ~70% at 400 nm (sulphide/sulphate electrolyte). The best results at wavelengths above 500 nm were achieved with CdS_xSe_y/TiO₂ cells at a molar ratio of 6:1 (S:Se) with IPCE of 40% at 500 nm and still 15% at 800 nm. Quantum efficiencies obtained with iodine/iodide electrolyte were lower and lead to an overall efficiency of 0.32%. The CdSxSey sensitized solar cells show enhanced stability compared to CdSe based systems and the use of the iodine/iodide electrolyte increases cell endurance further.

Keywords

Solar Cells; Nanocomposites; Cadmium Selenosulphide; Titanium Dioxide

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	B. O’Regan,M. Gr?tzel, “A Low-Cost, High-Efficiency Solar Cell Based on Dye-Sensitized Colloidal TiO2 Films,” Nature, Vol. 535, No. 6346, 1991, pp. 737-740. doi:10.1038/353737a0
[2]	M. Gr?tzel, “Photovoltaic and Photoelectrochemical Con- version of Solar Energy,” Philosophical Transactions of the Royal Society a-Mathematical Physical and Engi- neering Sciences, Vol. 365, No. 1853, 2007, pp. 993-1005. doi:10.1098/rsta.2006.1963
[3]	M. Gr?tzel, “Conversion of Sunlight to Electric Power by Nanocrystalline Dye-Sensitized Solar Cells,” Journal of Photochemistry and Photobiology A: Chemistry, Vol. 164, No. 1-3, 2004, pp. 3-14. doi:10.1016/j.jphotochem.2004.02.023
[4]	D. B. Kuang, C. Klein, Z. P. Zhang, S. Ito, J. E. Moser, S. M. Zakeeruddin and M. Gratzel, “Stable, High-Efficiency Ionic-Liquid-Based Mesoscopic Dye-Sensitized Solar Cells,” Small, Vol. 3, No. 12, 2007, pp. 2094-2102. doi:10.1002/smll.200700211
[5]	A. Zaban, O. I. Micic, B. A. Gregg and A. J. Nozik, “Photo-Sensitization of Nanoporous TiO2 Electrodes with InP Quantum Dots,” Langmuir, Vol. 14, No. 12, 1998, pp 3153-3156. doi:10.1021/la9713863
[6]	R. Vogel, P. Hoyer and H. Weller, “Quantum-Sized PbS, CdS, Ag2S, Sb2S3, and Bi2S3 Particles as Sensitizers for Various Nanoporous Wide-Bandgap Semiconductors,” Journal of Physical Chemistry B, Vol. 98, No. 12, 1994, pp. 3183-3188. doi:10.1021/j100063a022
[7]	R. Plass, S. Pelet, J. Krueger and M. Gr?tzel, “Quantum Dot Sensitization of Organic-Inorganic Hybrid Solar Cells,” Journal of Physical Chemistry B, Vol. 106, No. 31, 2002, pp. 7578-7580. doi:10.1021/jp020453l
[8]	L. M. Peter, K. G. U. Wijayantha and J. P. Waggett, “Band-Edge Tuning in Self-Assembled Layers of Bi2S3 Nanoparticles Used to Photosensitize Nanocrystalline TiO2,” Journal of Physical Chemistry B, Vol. 107, No. 33, 2003, pp. 8378-8381. doi:10.1021/jp030334l
[9]	P. Yu, K. Zhu, A. G. Norman, S. Ferrere, A. J. Frank, A. J. Nozik, “Nanocrystalline TiO2 Solar Cells Sensitized with InAs Quantum Dots,” Journal of Physical Chemistry B, Vol. 110, No. 50, 2006, pp. 25451-25454. doi:10.1021/jp064817b
[10]	L. M. Peter, D. J. Riley, E. J. Tull, K. G. U. Wijayantha, “Photosensitization of Nanocrystalline TiO2 by Self-As- sembled Layers of CdS Quantum Dots,” Chemical Communication, Vol. 10, 2002, pp. 1030-1031. doi:10.1039/b201661c
[11]	O. Niitsoo, S. K. Sarkar, C. Pejoux, S. Rühle, D. Cahen and G. Hodes, “Chemical Bath Deposited CdS/CdSe- Sensitized Porous TiO2 Solar Cells,” Journal of Photochemistry and Photobiology a-Chemistry, Vol. 181, No. 2-3, 2006, pp. 306-313. doi:10.1016/j.jphotochem.2005.12.012
[12]	I. Robel, V. Subramanian, M. Kuno and P. V. Kamat, “Quantum Dot Solar Cells. Harvesting Light Energy with CdSe Nanocrystals Molecularly Linked to Mesoscopic TiO2 Films,” Journal of the American Chemical Society, Vol. 128, No. 7, 2006, pp. 2385-2393. doi:10.1021/ja056494n
[13]	S. Rühle, M. Shalom and A. Zaban, “Quan- tum-Dot- Sensitized Solar Cells,” Journal of Chemical Physics and Physical Chemistry, Vol. 11, 2010, pp. 2290-2304. doi:10.1002/cphc.201000069
[14]	W. W. Yu, L. Qu, W. Guo and X. Peng, “Experimental Determination of the Extinction Coefficient of CdTe, CdSe, and CdS Nanocrystals,” Chemistry of Materials, Vol. 15, No. 14, 2003, pp. 2854-2860. doi.:10.1021/cm034081k
[15]	R. D. Schaller, V. M. Agranovich and V. I. Klimov, “High-Efficiency Carrier Multiplication through Direct Photogeneration of Multi-Excitons via Virtual Single-Exciton States,” Nature Physics, Vol. 1, No. 3, 2005, pp. 189-194. doi:10.1038/nphys151
[16]	M. C. Beard, K. P. Knutsen, P. R. Yu, J. M. Luther, Q. Song, W. K. Metzger, R. J. Ellingson and A. J. Nozik, “Multiple Exciton Generation in Colloidal Silicon Nanocrystals,” Nano Letters, Vol. 7, No. 8, 2007, pp. 2506-2512. doi:10.1021/nl071486l
[17]	A. J. Nozik, “Quantum Dot Solar Cells,” Physica E-Low-Dimensional Systems & Nanostructures, Vol. 14, No. 1-2, 2002, pp.115-120. doi:10.1016/S1386-9477(02)00374-0
[18]	V. I. Klimov, “Spectral and Dynamical Properties of Multiexcitons in Semiconductor Nanocrystals,” Annual Review of Physical Chemistry, Vol. 58, No. 1, 2007, pp. 635-673. doi:10.1146/annurev.physchem.58.032806.104537
[19]	K. C. Mandal and O. Savadogo, “Chemically Deposited n-CdSe Thin Film Photo-Electrochemical Cells: Effects of Zn2+-Modification,” Journal of Materials Science, Vol. 27, No. 16, 1992, pp. 4355-4360. doi:10.1007/BF00541566
[20]	Q. Shen, T. Sato, M. Hashimoto, C. C. Chen and T. Toyoda, “Photoacoustic and Photoelectrochemical Characterization of CdSe-Sensitized TiO2 Electrodes Composed of Nanotubes and Nanowires,” Thin Solid Films, Vol. 499, No. 1-2, 2006, pp. 299-305. doi:10.1016/j.tsf.2005.07.019
[21]	N. Fuke, L. B. Hoch, A. Y. Koposov, V. W. Manner, D. J. Werder, A. Fukui, N. Koide, H. Katayama and M. Sykora, “CdSe Quantum-Dot-Sensitized Solar Cell with ~100% Internal Quantum Efficiency,” ACS Nano, Vol. 4, No. 11, 2010, pp. 6377-6386. doi:10.1021/nn101319x
[22]	S. Gimenez, I. Mora-Sero, L. Macor, N. Guijarro, T. Lana-Villareal, R. Gomez, L. J. Diguna, Q. Shen, T. To- yoda and J. Bisquert, “Improving the Performance of Colloidal Quantum-Dot-Sensitized Solar Cells,” Nanotech- nolgy, Vol. 20, No. 29, 2009, Article ID: 295304. doi:10.1088/0957-4484/20/29/295204
[23]	J. Chen, J. L. Song, X. W. Sun, W. Q. Deng, C. Y. Jiang, W. Lei, J. H. Huang and R. S. Liu, “An Oleic Acid-Capped CdSe Quantum-Dot Sensitized Solar Cell,” Applied Physics Letters, Vol. 94, No. 15, 2009, Article ID: 153115. doi:10.1063/1.3117221
[24]	H. J. Lee, D. Y. Kim, J. S. Yoo, J. Bang, S. Kim and S. M. Park, “Anchoring Cadmium Chalcogenide Quantum Dots (QDs) onto Stable Oxide Semiconductors for QD Sensitized Solar Cells,” Bulletin of the Korean Chemical Society, Vol. 28, No. 6, 2007, pp. 953-958. doi:10.5012/bkcs.2007.28.6.953
[25]	S. Gorer and G. Hodes, “Quantum Size Effects in the Study of Chemical Solution Deposition Mechanisms of Semiconductor Films,” The Journal of Physical Chemistry, Vol. 98, No. 20, 1994, pp. 5338-5346. doi:10.1021/j100071a026
[26]	Y. Lee and Y.-S. Lo, “Highly Efficient Quantum- Dot-Sensitized Solar Cell Based on Co-Sensitization of CdS/CdSe,” Advanced Functional Materials, Vol. 19, No. 4, 2009, pp. 604-609. doi:10.1002/adfm.200800940
[27]	T. Toyoda, K. Oshikane, D. Li, Y. Luo, Q. Meng and Q. Shen, “Photoacoustic and Photoelectrochemical Current Spectra of Combined CdS/CdSe Quantum Dots Adsorbed on Nanostructured TiO2 Electrodes, Together with Photovoltaic Characteristics,” Journal of Applied Physics, Vol. 108, 2010, Article ID: 114304. doi:10.1063/1.3517066
[28]	T. Mahalingam, S. Thanikaikarasan, M. Raja, C. Sanjee- viraja, S. Lee, H. Moon, Y. D. Kim and P. J. Sebastian, “Studies on Electrochemically Grown Cd-Fe-Se Thin Films,” Journal of New Materials for Electrochemical Systems, Vol. 10, 2007, pp. 33-37.
[29]	R. Chandramohan, T. Mahalingam, J. P. Chu and P. J. Sebastian, “Preparation and Characterization of Semiconducting Zn1?xCdxSe Thin Films,” Solar Energy Materials and Solar Cells, Vol. 81, 2004, pp. 371-378. doi:10.1016/j.solmat.2003.11.013
[30]	X. Mathew, N. R. Mathews, P. J. Sebastian and C. O. Flores, “Deep Levels in the Band Gap of CdTe Films Electrodeposited from an Acidic Bath—PICTS Analysis,” Solar Energy Materials and Solar Cells, Vol. 81, No. 3, 2004, pp. 397-405. doi:10.1016/j.solmat.2003.11.015
[31]	X. Mathew, G. W. Thompson, V. P. Singh, J. C. McClure, S. Velumani, N. R. Mathews and P. J. Sebastian, “De- velopment of CdTe Thin Films on Flexible Substrates—A Review,” Solar Energy Materials and Solar Cells, Vol. 76, No. 3, 2003, pp. 293-303. doi:10.1016/S0927-0248(02)00281-7
[32]	T. Mahalingam, C. Sanjeeviraja and S. R. Srikumar, “Studies on Electrochemically Deposited CdSe Thin Films,” Bulletin of Electrochemistry, Vol. 12, 1996, pp. 148-150.
[33]	P. Mahawela, G. Sivaraman, S. Jeedigunta, J. Gaduputi, M. Ramalingam, S. Subramanian, S. Vakkalanka, C. S. Ferekides and D. L. Morel, “II–VI Compounds as the Top Absorbers in Tandem Solar Cell Structures,” Materials Science and Engineering B-Solid State Materials for Advanced Technology, Vol. 16, 2005, pp. 283-291. doi:10.1016/j.mseb.2004.05.054
[34]	S. Vakkalanka, C. S. Ferekides, D. L. Morel, “Development of ZnSexTe1—x p-Type Contacts for High Efficiency Tandem Structures,” Thin Solid Films, Vol. 515, No. 15, 2007, pp. 6132-6135. doi:10.1016/j.tsf.2006.12.160
[35]	L. Y. Zeng, S. Y. Dai, W. W. Xu and K. J. Wang, “Dye-Sensitized Solar Cells Based on ZnO Films,” Plasma Science & Technology, Vol. 8, No. 2, 2006, pp. 172-175. doi:org/10.1088/1009-0630/8/2/10
[36]	T. Aramoto, F. Adurodija, Y. Nishiyama, T. Arita, A. Hanafusa, K. Omura and A. Morita, “A New Technique for Large-Area Thin Film CdS/CdTe Solar Cells,” Solar Energy Materials and Solar Cells, Vol. 75, No. 1, 2003, pp. 211-217. doi:10.1016/FS0927-0248(02)00161-7
[37]	H. Uda, H. Sonomura and S. Ikegami, “Screen Printed CdS/CdTe Cells for Visible-Light-Radiation Sensor,” Measurement Science & Technology, Vol. 8, No. 6, 1997, pp. 86-91. doi:10.1088/0957-0233/8/1/012
[38]	A. L. Rogach, A. Kornowski, M. Gao, A. Eychmüller and H. Weller, “Synthesis and Characterization of a Size Series of Extremely Small Thiol-Stabilized CdSe Nanocrys- tals,” The Journal of Physical Chemistry B, Vol. 103, No. 16, 1999, pp. 3065-3069. doi:10.1021/jp984833b
[39]	G. A. Martínez-Casta?ón, M. G. Sánchez-Loredo, J. R. Martínez-Mendoza, F. Ruiz, “Synthesis of CdS Nanoparticles: A Simple Method in Aqueous Media,” Azojomo, Vol. 1, 2005, pp. 1-2. doi:10.2240/azojomo00170
[40]	V. G. Kulkarni and P. D. Garn, “Study of the Formation of Cadmium Sulfoselenide,” Thermochimica Acta, Vol. 99, 1986, pp. 33-36. doi:10.1016/0040-6031(86)85262-5
[41]	J. Yu, X. Zhao, J. Du and W. Chen, “Preparation, Microstructure and Photocatalytic Activity of the Porous TiO2 Anatase Coating by Sol-Gel Processing,” Journal of sol-gel Science and Technology, Vol. 17, 2000, pp. 163-171. doi:10.1023/A:1008703719929
[42]	S. Barazzouk and S. Hotchandani, “Enhanced Charge Separation in Chlorophyll a Solar Cell by Gold Nanoparticles,” Journal of Applied Physics, Vol. 96, No. 12, 2004, pp. 7744-7746. doi:10.1063/1.1811775
[43]	A. Hagfeldt, G. Boschloo, L. Sun, L. Klo, H. Pettersson, “Dye-Sensitized Solar Cells,” Chemical Reviews, Vol. 101, No. 11, 2010, pp. 6595-6663. doi:10.1021/cr900356p