Effect of the Presence of Iodide on the Electron Injection Dynamics of Dye-Sensitized TiO_2-Based Solar Cells
Abstract
The electron injection dynamics of dye-sensitized TiO_2-based solar cells have been investigated to determine the effects of replacing the I_3^−/I^− redox system by non-redox-active supporting electrolytes. TiO-2 films were sensitized with Ru(dcbpy)_2(NCS)_2, where dcbpy = 4,4′-dicarboxylic acid-2,2′-bipyridine (the "N3" dye), and placed in contact with either M(ClO_4) or M(I_3−/I−) solutions (M = Li^+ or (n-C_4H_9)_4N^+); cells that contained I_3−/I− were fully functional solar cells whose steady-state photocurrents were directly measured. In (n-C_4H_9)_4N^+-containing solutions, significant differences were observed between the measured kinetics when ClO_4^− was replaced by the redox-active I3^−/I^− system. In particular, a ps time scale loss of the metal-to-ligand charge-transfer excited-state of the N3 dye, associated with electron injection, that was observed in cells containing either LiClO_4 or [(n-C_4H_9)4N]ClO_4 was absent in fully functional solar cells that contained [(n-C_4H_9)_4N]I/I_2. These results underscore the importance of performing kinetics measurements on this class of solar cells under operational conditions if one is to obtain reliable correlations between the dynamics data and the steady-state performance metrics of the solar cell devices.
Additional Information
© 2008 American Chemical Society. Received 18 April 2008. Published online 23 July 2008. Published in print 1 August 2008. Research was in part carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. This work was supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Science, U.S. Department of Energy Grants DE-FG02-03ER15483 (N.S.L.) and DE-FG02-01ER15282 (J.K.M.).Attached Files
Supplemental Material - jp803402x-file001.pdf
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Additional details
- Eprint ID
- 79195
- Resolver ID
- CaltechAUTHORS:20170719-090248351
- Caltech Beckman Institute
- Department of Energy (DOE)
- DE-FG02-03ER15483
- Department of Energy (DOE)
- DE-FG02-01ER15282
- Created
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2017-07-19Created from EPrint's datestamp field
- Updated
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2021-11-15Created from EPrint's last_modified field