Evidence against surface state limitations on efficiency of p-Si/CH₃CN junctions
Abstract
We report here the first efficient p-type Si-based semiconductor–liquid junction system. p-Type Si photocathodes have been previously reported to yield open circuit photovoltages, V_(oc), of 0.38–0.40 V with several redox systems. Photocurrent–voltage studies of p-Si cathodes in CH3CN solvent have demonstrated 2.5% efficiency for conversion of 632.8-nm light to electricity with the N,N′-dimethyl-4,4′-bipyridinium^(2+/+) redox system1, and 0.5–2.4% with other macrocyclic complexes. Such modest energy conversion efficiencies for small band gap semiconductors have been attributed to surface states which pin the semiconductor Fermi level and promote recombination processes. However, we find that p-type Si/CH₃CN interfaces can yield solar conversion efficiencies in excess of 10%, and can display open circuit photovoltages within 0.08 V of the theoretical limit for an ideal junction.
Additional Information
© 1984 Nature Publishing Group. We thank G. Cogan and J. Gibbons for helpful discussions, and for access to spectral response and metal evaporation facilities at SERA Solar Corporation. We acknowledge a Cottrell Grant from the Research Corporation for partial support of this work.Additional details
- Eprint ID
- 120943
- Resolver ID
- CaltechAUTHORS:20230417-377915000.37
- Cottrell Scholar of Research Corporation
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2023-04-18Created from EPrint's datestamp field
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2023-04-18Created from EPrint's last_modified field