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Current Challenges in Organic Photovoltaic Solar Energy Conversion

Chapter
First Online:
Part of the Topics in Current Chemistry book series (TOPCURRCHEM, volume 312)

Abstract

Over the last 10 years, significant interest in utilizing conjugated organic molecules for solid-state solar to electric conversion has produced rapid improvement in device efficiencies. Organic photovoltaic (OPV) devices are attractive for their compatibility with low-cost processing techniques and thin-film applicability to flexible and conformal applications. However, many of the processes that lead to power losses in these systems still remain poorly understood, posing a significant challenge for the future efficiency improvements required to make these devices an attractive solar technology. While semiconductor band models have been employed to describe OPV operation, a more appropriate molecular picture of the pertinent processes is beginning to emerge. This chapter presents mechanisms of OPV device operation, based on the bound molecular nature of the involved transient species. With the intention to underscore the importance of considering both thermodynamic and kinetic factors, recent progress in elucidating molecular characteristics that dictate photovoltage losses in heterojunction organic photovoltaics is also discussed.

Keywords

Charge-transfer state Organic electronics Organic solar cells Photovoltaics Solar energy 
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Notes

Acknowledgements

The authors gratefully acknowledge support from the Center for Energy Nanoscience, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under award number DE-SC0001013, from the Center for Advanced Molecular Photovoltaics (Award No KUS-C1-015-21), made by King Abdullah University of Science and Technology (KAUST), and from Global Photonic Energy Corporation.

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© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  1. 1.Department of Chemistry and the Center for Energy NanoscienceUniversity of Southern CaliforniaLos AngelesUSA

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