SCIENCE CHINA Materials, Volume 64 , Issue 12 : 2915-2925(2021) https://doi.org/10.1007/s40843-021-1705-8

A novel dopant for spiro-OMeTAD towards efficient and stable perovskite solar cells

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  • ReceivedMar 3, 2021
  • AcceptedMay 10, 2021
  • PublishedJul 6, 2021



the National Key Research and Development Plan(2019YFE0107200,2017YFE0131900)

the National Natural Science Foundation of China(21875178,91963209)

and Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(XHD2020-001,XHT2020-005)


This work was financially supported by the National Key Research and Development Plan (2019YFE0107200 and 2017YFE0131900), the National Natural Science Foundation of China (21875178 and 91963209), and Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory (XHD2020-001 and XHT2020-005). The Analytical and Testing Centre of Wuhan University of Technology and Hubei Key Laboratory of Low Dimensional Optoelectronic Material and Devices, Hubei University of Arts and Science is acknowledged for the XPS, XRD and SEM characterizations.

Interest statement

The authors declare that they have no conflict of interest.

Contributions statement

Huang F and Bu T proposed and supervised the project. Lin Z conducted most of the experiments and analyzed the data as well as wrote the manuscript. Li J contributed to the experimental scheme and materials selection. Li H and Pan J performed the PL measurement. Mo Y and Wang C performed the stability test. Zhang XL, Zhong J, and Cheng YB revised the manuscript. All the authors contributed to the general discussion.

Author information

Zhipeng Lin received his BS degree from Wuhan University of Technology (WUT) in 2019. He is currently a master degree candidate at Wuhan University of Technology. His current research interest is focused on the field of perovskite solar cells.

Tongle Bu received his PhD from WUT in 2019. He joined Okinawa Institute of Science and Technology Graduate University (OIST) as a postdoctoral fellow in 2020. He is currently working on the scalable printing of efficient and stable perovskite solar cells and modules.

Fuzhi Huang received his PhD in chemistry (2009) from The University of Melbourne, Australia. Currently, he is a full professor at the State Key Lab of Advanced Technology for Materials Synthesis and Processing, WUT. His research interest is developing new materials and techniques for high-efficiency organic-inorganic hybrid perovskite solar cells.

Supplementary data

Supplementary information

Supporting data are available in the online version of the paper.


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  • Figure 1

    (a) A typical normal structure of planar PSCs, and the molecular structure of spiro-OMeTAD. (b, c) The schematic of the different dopants and solvents for HTL. (d–f) AFM images of the perovskite film, perovskite/Li-spiro, and perovskite/K-spiro, respectively.

  • Figure 2

    (a) J-V characteristics of hole-only devices of pristine spiro-OMeTAD, Li-spiro and K-spiro films. (b) Steady-state PL and (c) TRPL measurements of perovskite (PSK), perovskite/Li-spiro and perovskite/K-spiro films.

  • Figure 3

    (a) The J-V curves of the champion Li-spiro and K-spiro devices tested under 1 Sun AM 1.5G. (b) The corresponding EQE spectra of these devices. (c) Steady-state output of photocurrent density measured at the MPP and illuminated under 1 Sun AM 1.5G. (d) Statistical distribution of the PCEs for the Li-spiro and K-spiro devices under RS and FS.

  • Figure 4

    The TOF-SIMS depth profiles of (a) Li-spiro device and (b) K-spiro device. The XPS spectra of perovskite films after removal of (c) Li-spiro and (d) K-spiro deposited five days ago.

  • Figure 5

    (a) The long-term photo-stability of devices under continuous 0.6 sun light illumination in air with encapsulation. (b) Stability test of the devices without encapsulation aged in air (relative humidity 25%, at 25°C). Contact angle measurements of (c) Li-spiro and (d) K-spiro films.

  • Table 1   Photovoltaic characteristics of PSCs prepared with different HTLs



    VOC (V)


    (mA cm−2)


    PCE (%)



























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