Review Article | Published:

The role of the third component in ternary organic solar cells

Nature Reviews Materialsvolume 4pages229242 (2019) | Download Citation


Ternary organic solar cells (TSCs) contain a single three-component photoactive layer with a wide absorption window, which is obtained without the need for multiple stacks. Subsequently, TSCs have attracted great interest in the photovoltaics field. Through careful selection of the three (or more) active components that form the photoactive layer, all photovoltaic parameters can be simultaneously enhanced within a TSC — a strategy that has resulted in record efficiencies for single-junction solar cells. In this Review, we outline key developments in TSCs, with a focus on the central role of the third component in achieving record efficiencies. We analyse the effects of the third component on the nanomorphology of the bulk heterojunction and the photovoltaic parameters of TSCs. Moreover, we discuss the charge-transfer and/or energy-transfer mechanisms and nanomorphology models that govern the operation of TSCs. We consider both polymer and small-molecule donors as well as fullerenes and recently developed non-fullerene acceptors. In addition, we summarize the recent success of TSCs in mitigating the stability issues of binary solar cells. Finally, we provide a perspective on the advantages of ternary blends and suggest design strategies for highly efficient and stable devices for commercial photovoltaics.

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The authors acknowledge funding from the King Abdullah University of Science and Technology (KAUST) and thank the UK Engineering and Physical Sciences Research Council (EPSRC) for financial support (project EP/G037515/1, EP/M005143/1, ECFP7 and project SC2 (610115)). A.S. acknowledges support from the US National Science Foundation (CBET award no. 1510481).

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  1. King Abdullah University of Science and Technology (KAUST), Division of Physical Sciences and Engineering (PSE), KAUST Solar Center (KSC), Thuwal, Saudi Arabia

    • Nicola Gasparini
    • , Iain McCulloch
    •  & Derya Baran
  2. Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA

    • Alberto Salleo
  3. Department of Chemistry and Centre for Plastic Electronics, Imperial College London, London, UK

    • Iain McCulloch


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D.B. and N.G. researched data for the article. A.S. wrote the morphology-related sections. I.M. wrote the sections on chemical design and stability. N.G. wrote the charge transport and recombination section. D.B. wrote the sections on operating modes of TSCs, energetics and the introduction. All authors discussed, edited and reviewed the article before submission.

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The authors declare no competing interests.

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Correspondence to Derya Baran.

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