Solid-state And Flexible Solar Cells Based On Dye-sensitized Tio2: Study By Electrochemical Impedance Spectroscopy

Dye sensitized TiO2 solar cells were assembled using rigid or flexible transparent electrodes (a conductive film deposited on glass or poly(ethylene terephthalate) as substrates and a polymer electrolyte based on I3 -/I2 and poly(epichlorohydrin-co-ethylene oxide). The cells were characterized by current-potential curves and electrochemical impedance spectroscopy under different light intensities. Under 100 mWcm-2 illumination, the rigid cell exhibited an open circuit potential VOC = 0.75 V, a short-circuit photocurrent ISC = 2.5 mAcm-2 and an efficiency η = 0.9 %; for the flexible cell, VOC = 0.83 V and η and Isc were almost 10 times smaller. Under illumination, impedance spectra exhibited three semi-circles for the rigid cell. For the flexible cell the time constants were not well defined. In the dark, both systems presented very high impedance. The differences in the efficiency and the impedance spectra of both cells were compared and discussed.44652130Nazeeruddin, M.K., Kay, A., Rodicio, I., Humphry, R., Muller, E., Liska, P., Vlachopoulos, N., Grätzel, M., (1993) J. Am. Chem. Soc., 115, p. 6382Hagfeldt, A., Grätzel, M., (1995) Chem. Rew., 95, p. 49Pelet, S., Moser, J.-E., Grätzel, M., (2000) J. Phys. Chem. B, 104, p. 1791Kang, T.-S., Chun, K.-H., Hong, J.S., Moon, S.-H., Kim, K.-J., (2000) J. Electrochem. Soc., 147, p. 3049Van Lagemaat, J., Park, N.G., Frank, A.J., (2000) J. Phys. Chem. B, 104, p. 2044Franco, G., Gehring, J., Peter, L.M., Ponomarev, E.A., Uhlendorf, I., (1999) J. Phys. Chem. B, 103, p. 692Peter, L.M., Ponomarev, E.A., Franco, G., Shaw, N.J., (1999) Electrochim. Acta, 45, p. 549Franco, G., Peter, L.M., Ponomarev, E.A., (1999) Electrochem. Commun., 1, p. 61Van der Zanden, B., Goossens, A., (2000) J. Phys. Chem. B, 104, p. 7171Schlichthörl, G., Huang, S., Sprague, J., Frank, A.J., (1997) J. Phys. Chem. B, 101, p. 8141Nogueira, A.F., Spinacé, M.A., Gazotti, W.A., Girotto, E.M., De Paoli, M.-A., (2001) Solid State Ionics, 140, p. 327Nogueira, A.F., M.-A. De Paoli, (2000) Sol. Energy Mater. Sol. Cells, 61, p. 135Nogueira, A.F., Durrant, J.R., De Paoli, M.-A., (2001) Adv. Mater., 13, p. 826Nogueira, A.F., De Paoli, M.-A., Montanari, I., Monkhouse, R., Nelson, J., Durrant, J.R., (2001) J. Phys. Chem., 105, p. 7517Longo, C., Machado, D.A., Nogueira, A.F., De Paoli, M.-A., (2001) Electrochim. Acta., 46, p. 4243Topoglidis, E., Lutz, T., Willis, R., Barnett, C., Cass, A.E.G., Durant, J.R., J.C.S. Faraday Disc., , in pressBoukamp, B.A., (1995) EQUIVCRT, version 4.51, , University of Twente, The NetherlandsSommeling, P.M., Späth, M., Kroon, J., Kinderman, R., Van Roosmalen, J., (2000) Proceedings of the 16th European Photovoltaic Solar Energy Conference and Exhibition, , Glasgow, May 1-5, 2000Pichot, F., Ferrere, S., Pitts, R.J., Gregg, B.A., (1999) J. Electrochem. Soc., 146, p. 4324Hagfeldt, A., Didriksson, B., Palmqvist, T., Lindström, H., Södergren, S., Rensmo, H., Lindquist, S.E., (1994) Sol. Energy Mater. Solar Cells, 31, p. 481Macdonald, J.R., (1987) Impedance Spectroscopy, p. 133. , J.R. Macdonald ed., John Wiley, New YorkVan der Zanden, B., Goossens, A., (2000) J. Phys. Chem. B, 104, p. 717