Letter | Published:

Single-junction polymer solar cells with high efficiency and photovoltage

Nature Photonics volume 9, pages 174179 (2015) | Download Citation

Abstract

Polymer solar cells are an exciting class of next-generation photovoltaics, because they hold promise for the realization of mechanically flexible, lightweight, large-area devices that can be fabricated by room-temperature solution processing1,2. High power conversion efficiencies of 10% have already been reported in tandem polymer solar cells3. Here, we report that similar efficiencies are achievable in single-junction devices by reducing the tail state density below the conduction band of the electron acceptor in a high-performance photoactive layer made from a newly developed semiconducting polymer with a deepened valence energy level. Control over band tailing is realized through changes in the composition of the active layer and the structure order of the blend, both of which are known to be important factors in cell operation4,5,6. The approach yields cells with high power conversion efficiencies (9.94% certified) and enhanced photovoltage.

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Acknowledgements

The authors thank M. Yun and X. Wang for device performance verification. H.W., Z.H. and Y.C. thank the National Nature Science Foundation of China (nos. 51225301, 51403066, 91333206 and 51010003), the Fundamental Research Funds for the Central Universities (2014ZM001) and the Ministry of Science and Technology of China (2014CB643500) for financial support. F.L. and T.P.R. thank Polymer-Based Materials for Harvesting Solar Energy (PHaSE), an Energy Frontier Research Center funded by the US Department of Energy, Office of Basic Energy Sciences (DE-SC0001087), for support. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract no. DE-AC02-05CH11231.

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Affiliations

  1. Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China

    • Zhicai He
    • , Biao Xiao
    • , Hongbin Wu
    •  & Yong Cao
  2. Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, USA

    • Feng Liu
    •  & Thomas P. Russell
  3. 1-material Inc., 2290 St-Francois, Dorval, Quebec H9P 1K2, Canada

    • Yali Yang
    •  & Steven Xiao
  4. Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA

    • Cheng Wang

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Contributions

H.W., Z.H. and B.X. conceived the idea and designed the experiments. Z.H. fabricated and characterized the devices. F.L., C.W. and T.P.R. conducted structure characterizations. Y.Y. and S.X. synthesized the electron donor. H.W. and Y.C. coordinated and directed the study. All authors contributed to manuscript preparation, data analysis and interpretation, and discussed the results.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Hongbin Wu.

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DOI

https://doi.org/10.1038/nphoton.2015.6

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