The authors gratefully acknowledge support from the U.S. Department of Energy for Institute of Advanced Materials at the University of Louisville (DE-FG02-05ER64071) and DoE-EPSCoR program (DE-FG02-07ER46375). Supporting Information is available online from Wiley InterScience or from the authors.
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Full Paper
Band-Edge Engineered Hybrid Structures for Dye-Sensitized Solar Cells Based on SnO2 Nanowires†
Article first published online: 28 JUL 2008
DOI: 10.1002/adfm.200800099
Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Additional Information
How to Cite
Gubbala, S., Chakrapani, V., Kumar, V. and Sunkara, M. K. (2008), Band-Edge Engineered Hybrid Structures for Dye-Sensitized Solar Cells Based on SnO2 Nanowires. Adv. Funct. Mater., 18: 2411–2418. doi: 10.1002/adfm.200800099
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Publication History
- Issue published online: 19 AUG 2008
- Article first published online: 28 JUL 2008
- Manuscript Revised: 2 MAY 2008
- Manuscript Received: 21 JAN 2008
Keywords:
- Dye-sensitized solar cells;
- Hybrid structures;
- Inorganic nanoparticles;
- Inorganic nanowires;
- tin oxide;
- titania
Abstract
In this report, we show for the first time that SnO2 nanowire based dye sensitized solar cells exhibit an open circuit voltage of 560 mV, which is 200 mV higher than that using SnO2 nanoparticle based cells. This is attributed to the more negative flat band potential of nanowires compared to the nanoparticles as determined by open circuit photo voltage measurements made at high light intensities. The nanowires were employed in hybrid structures consisting of highly interconnected SnO2 nanowire matrix coated with TiO2 nanoparticles, which showed an open circuit voltage of 720 mV and an efficiency of 4.1% compared to 2.1% obtained with pure SnO2 nanowire matrix. The electron transport time constants for SnO2 nanowire matrix were an order of magnitude lower and the recombination time constants are about 100 times higher than that of TiO2 nanoparticles. The higher efficiency observed for DSSCs based on hybrid structure is attributed to the band edge positions of SnO2 relative to that of TiO2 and faster electron transport in SnO2 nanowires.