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High fabrication yield organic tandem photovoltaics combining vacuum- and solution-processed subcells with 15% efficiency

Nature Energyvolume 3pages422427 (2018) | Download Citation



Multijunction solar cells are effective for increasing the power conversion efficiency beyond that of single-junction cells. Indeed, the highest solar cell efficiencies have been achieved using two or more subcells to adequately cover the solar spectrum. However, the efficiencies of organic multijunction solar cells are ultimately limited by the lack of high-performance, near-infrared absorbing organic subcells within the stack. Here, we demonstrate a tandem cell with an efficiency of 15.0 ± 0.3% (for 2 mm2 cells) that combines a solution-processed non-fullerene-acceptor-based infrared absorbing subcell on a visible-absorbing fullerene-based subcell grown by vacuum thermal evaporation. The hydrophilic–hydrophobic interface within the charge-recombination zone that connects the two subcells leads to >95% fabrication yield among more than 130 devices, and with areas up to 1 cm2. The ability to stack solution-based on vapour-deposited cells provides significant flexibility in design over the current, all-vapour-deposited multijunction structures.

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This work was supported by the SunShot Program of the Department of Energy under award no. DE-EE0006708 (X.C., experiment, analysis; S.R.F., analysis) and the Department of the Navy, Office of Naval Research, under award no. N00014-17-1-2211 (Y.L. and Y.Q, experiment and analysis). We thank T. Moriarty and D. Levi from NREL for the photovoltaic device performance calibration service.

Author information


  1. Applied Physics Program, University of Michigan, Ann Arbor, MI, USA

    • Xiaozhou Che
    •  & Stephen R. Forrest
  2. Departments of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, USA

    • Yongxi Li
    • , Yue Qu
    •  & Stephen R. Forrest
  3. Department of Physics, University of Michigan, Ann Arbor, MI, USA

    • Stephen R. Forrest


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X.C. designed and fabricated all the solar cell samples, conducted the measurements and performed data analysis. Y.L. contributed to the non-fullerene acceptor-based subcell design and data analysis. Y.Q. designed and helped fabricate and characterize the antireflecting coating structure. S.R.F. supervised the project and analysed data. X.C. and S.R.F. prepared the manuscript.

Competing interests

The authors declare no competing interests.

Corresponding author

Correspondence to Stephen R. Forrest.

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  1. Supplementary Information

    Supplementary Figures 1–7, Supplementary Table 2, Supplementary References

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