Organic solar cells (OSCs) have been dominated by donor:acceptor blends based on fullerene acceptors for over two decades. This situation has changed recently, with non-fullerene (NF) OSCs developing very quickly. The power conversion efficiencies of NF OSCs have now reached a value of over 13%, which is higher than the best fullerene-based OSCs. NF acceptors show great tunability in absorption spectra and electron energy levels, providing a wide range of new opportunities. The coexistence of low voltage losses and high current generation indicates that new regimes of device physics and photophysics are reached in these systems. This Review highlights these opportunities made possible by NF acceptors, and also discuss the challenges facing the development of NF OSCs for practical applications.
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We thank Thomas Kirchartz for insightful discussions. The work was supported by the National Natural Science Foundation of China (grant nos 91633301, 91333204, 51673201, 21325419 and 51711530159), the Chinese Academy of Sciences (grant no. XDB12030200), the Swedish Research Council VR (grant nos 2017-00744 and 2016-06146), the Swedish Energy Agency Energimyndigheten (2016-010174), the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (faculty grant no. SFO-Mat-LiU #2009-00971), the Engineering and Physical Sciences Research Council in the UK, and the Knut and Alice Wallenberg foundation (KAW) through a Wallenberg Scholar grant to O.I.
The authors declare no competing financial interests.
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Hou, J., Inganäs, O., Friend, R. et al. Organic solar cells based on non-fullerene acceptors. Nat. Mater. 17, 119–128 (2018). https://doi.org/10.1038/nmat5063
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