Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-27T20:34:14.087Z Has data issue: false hasContentIssue false
  • English
  • Français

The Photoconversion Mechanism of Excitonic Solar Cells

Published online by Cambridge University Press:  31 January 2011

Brian A. Gregg
Get access

Abstract

Excitonic solar cells (XSCs) function by a mechanism that is different than that of conventional solar cells.They have different limitations on their open circuit photovoltages, and their behavior cannot be interpreted as if they were conventional p–n heterojunctions. Exciton dissociation at the heterojunction produces electrons on one side of the interface already separated from the holes produced on the other side of the interface. This creates a powerful photoinduced interfacial chemical potential energy gradient that drives the photovoltaic effect, even in the absence of a built-in electrical potential. The maximum thermodynamic efficiency achievable in an XSC is shown to be identical to that of a conventional solar cell, with the substitution of the optical bandgap in the XSC for the electronic bandgap in the conventional cell. This article briefly reviews the photovoltaic mechanism of XSCs, the limitations on their photovoltage, and their maximum achievable efficiency.

Keywords

efficiency limitationsexcitonic mechanismorganic solar cells.
Type
Research Article
Information
MRS Bulletin , Volume 30 , Issue 1: Technical Theme: Organic–Based Photovoltaics , January 2005 , pp. 20 - 22
Copyright
Copyright © Materials Research Society 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.O'Regan, B. and Grätzel, M., Nature 353 (1991) p. 737.CrossRefGoogle Scholar
2.Kalyanasundaram, K. and Grätzel, M., Coord. Chem. Rev. 77 (1998) p. 347.CrossRefGoogle Scholar
3.Nazeeruddin, M.K., Kay, A., Rodicio, I., Humphry-Baker, R., Müller, E., Liska, P., Vlachopoulos, N., and Grätzel, M., J. Am. Chem. Soc. 115 (1993) p. 6382.CrossRefGoogle Scholar
4.O'Regan, B., Moser, J., Anderson, M., and Grätzel, M., J. Phys. Chem. 94 (1990) p. 8720.CrossRefGoogle Scholar
5.Gregg, B.A., in Semiconductor Photochemistry and Photophysics, Vol. 10, edited by Schanze, K.S. and Ramamurthy, V. (Marcel Dekker, New York, 2002) p. 51.Google Scholar
6.Peumans, P., Bulovic, V., and Forrest, S.R., Appl. Phys. Lett. 76 (2000) p. 2650.Google Scholar
7.Gregg, B.A., Chem. Phys. Lett. 258 (1996) p. 376.CrossRefGoogle Scholar
8.Tang, C.W., Appl. Phys. Lett. 48 (1986) p. 183.CrossRefGoogle Scholar
9.Yu, G., Gao, J., Hummelen, J.C., Wudl, F., and Heeger, A.J., Science 270 (1995) p. 1789.CrossRefGoogle Scholar
10.Halls, J.J.M., Walsh, C.A., Greenham, N.C., Marseglia, E.A., Friend, R.H., Moratti, S.C., and Holmes, A.B., Nature 376 (1995) p. 498.CrossRefGoogle Scholar
11.Huynh, W.U., Dittmer, J.J., and Alivisatos, A.P., Science 295 (2002) p. 2425.Google Scholar
12.Granström, M., Petritsch, K., Arias, A.C., Lux, A., Andersson, M.R., and Friend, R.H., Nature 395 (1998) p. 257.CrossRefGoogle Scholar
13.Shaheen, S.E., Brabec, C.J., Sariciftci, N.S., Padinger, F., and Fromherz, T., Appl. Phys. Lett. 78 (2001) p. 841.CrossRefGoogle Scholar
14.Gregg, B.A., in Molecules as Components in Electronic Devices, edited by Lieberman, M. (American Chemical Society, Washington, DC, 2003) p. 243.CrossRefGoogle Scholar
15.Gregg, B.A. and Hanna, M.C., J. Appl. Phys. 93 (2003) p. 3605.CrossRefGoogle Scholar
16.Gregg, B.A., J. Phys. Chem. B 107 (2003) p. 4688.CrossRefGoogle Scholar
17.Fahrenbruch, A.L. and Bube, R.H., Fundamentals of Solar Cells: Photovoltaic Solar Energy Conversion (Academic Press, New York, 1983).Google Scholar
18.Fonash, S.J., Solar Cell Device Physics (Academic Press, New York, 1981).Google Scholar
19.Gregg, B.A., Pichot, F., Ferrere, S., and Fields, C.L., J. Phys. Chem. B 105 (2001) p. 1422.Google Scholar
20.Prigogine, I., Thermodynamics of Irreversible Processes, 3rd ed. (Wiley, New York, 1967).Google Scholar
21.Gibbs, J.W., The Scientific Papers of J. Willard Gibbs, Vol. 1 (Dover, New York, 1961).Google Scholar
22.Pichot, F. and Gregg, B.A., J. Phys. Chem. B 104 (2000) p. 6.CrossRefGoogle Scholar
23.Schockley, W. and Queisser, H.J., J. Appl. Phys. 32 (1961) p. 510.CrossRefGoogle Scholar