Review Article

Low-bandgap conjugated polymers enabling solution-processable tandem solar cells

  • Nature Reviews Materials 2, Article number: 17043 (2017)
  • doi:10.1038/natrevmats.2017.43
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Abstract

The technology of polymer-based organic photovoltaic (OPV) cells has made great progress in the past decade, with the power conversion efficiency increasing from just a few per cent to around 12%, and the stability increasing from hours to years. One of the important milestones in this progress has been the invention of infrared-absorbing low-bandgap polymers, which allows the OPV cells to form effective tandem structures for harvesting near-infrared energy from the solar spectrum. In this Review, we focus on the progress in low-bandgap conjugated polymers and several tandem OPV cells enabled by these low-bandgap polymers. Specifically, we cover polymer-based tandem solar cells; hybrid tandem solar cells combining polymers with hydrogenated amorphous silicon; and unconventional solar cells. For each of these technologies, we address the challenges and offer our perspectives for future development.

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Acknowledgements

This work is supported by the US Office of Naval Research (ONR, Grant No. N00014-14-1-0648, programme director: P. Armistead), Air Force Office of Scientific Research (AFOSR, Grant No. FA2386–15-1–4108, programme director: C. Lee) and National Science Foundation (CHE 1230598, programme director: L. S. Sapochak; DMR 1335645, programme director: C. Ying). This work was also supported by the funding for Project of Strategic Importance provided by The Hong Kong Polytechnic University (project code: 1-ZE29). The authors thank I. Wang for help in editing and proofreading this article before submission.

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Affiliations

  1. Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California 90095, USA.

    • Gang Li
    • , Wei-Hsuan Chang
    •  & Yang Yang
  2. Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.

    • Gang Li

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Competing interests

The authors declare no competing interests.

Corresponding authors

Correspondence to Gang Li or Yang Yang.