SCIENCE CHINA Materials, Volume 63 , Issue 7 : 1142-1150(2020) https://doi.org/10.1007/s40843-020-1269-9

15.3% efficiency all-small-molecule organic solar cells enabled by symmetric phenyl substitution

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  • ReceivedJan 7, 2020
  • AcceptedFeb 14, 2020
  • PublishedMar 18, 2020


Funded by

the Basic and Applied Basic Research Major Program of Guangdong Province(2019B030302007)

and by the National Natural Science Foundation of China(NSFC)


This work was financially supported by the Basic and Applied Basic Research Major Program of Guangdong Province (2019B030302007), and the National Natural Science Foundation of China (51873217, 21734008, 51703228, 51961135103, 51773047 and 51903239).

Interest statement

The authors declare no conflict of interest.

Contributions statement

Hou J and He C conceived and designed the experiments; An C and Ma K synthesized and characterized the molecules; Zhang J, Tang Y and Ma W performed the GIWAXS measurements; Qin J fabricated the devices; Yang Y carried out the TEM measurements; All authors contributed to the general discussion.

Author information

Jinzhao Qin received his BSc degree in the Department of Polymer Science and Engineering from the University of Science and Technology of China. Now he is a PhD candidate in Prof. Jianhui Hou’s group in the Institute of Chemistry, Chinese Academy of Sciences (ICCAS). His current research focuses on organic photovoltaic devices.

Cunbin An received his PhD degree from Max Planck Institute for Polymer Research in 2015. After one-year postdoctoral research in the same group, he joined ICCAS as an assistant professor. His current research focuses on developing conjugated materials for organic photovoltaics.

Jianqi Zhang received his PhD degree in polymer physics and chemistry at Changchun Institute of Applied Chemistry, Chinese Academy of sciences in 2010. After that, he did postdoctoral research at Technische Universität München (TUM). He has been an associate professor at the National Center of Nanoscience and Technology (NCNST) since 2017. His research interests focus on using wide- and small-angle X-ray scattering to study complex structure-performance relationships of photovoltaic systems.

Chang He has been a professor at ICCAS since 2019. She graduated with a BSc degree in 1997 from Xi’an Jiaotong University. She obtained her PhD degree in physical chemistry from ICCAS in 2007. Her research interests focus on solution-processible small molecule photovoltaic materials and the related devices.

Jianhui Hou received his PhD degree from ICCAS in 2006. Then he worked as a postdoctoral researcher in Prof. Yang Yang’s group at the University of California at Los Angeles. He joined the Solarmer Energy Inc. (USA) in 2008 as a team leader of research department. He became a full professor of ICCAS since 2010, and his research focuses on the design, synthesis and application of the organic/polymer photovoltaic materials.


Supplementary information

Experimental details and supporting data are available in the online version of the paper.


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  • Figure 1

    (a) Chemical structures of the small moleculars donors B1 and BTR. (b) Optimized molecular structures of B1 and BTR obtained from the DFT-based theoretical calculations. (c) The total energy scans dependent on dihedral angles for model compounds BDT-B and BDT-T. (d) DSC traces of B1 and BTR in nitrogen at a rate of 10°C min−1. 2D GIWAXS pattern of the neat (e) B1 and (f) BTR films. (g) Extracted 1D profiles along the OOP direction of the neat B1 and BTR films.

  • Figure 2

    (a) Chemical structure of BO-4Cl. (b) Energy level diagrams. (c) J-V curves of the BTR:BO-4Cl- and B1:BO-4Cl-based devices. (d) EQE curves of the BTR:BO-4Cl- and B1:BO-4Cl-based devices. (e) J-V curve of the device measured by the NIM, China. (f) The statistical diagram of PCEs for 40 individual B1:BO-4Cl-based devices with CB SVA treatment.

  • Figure 3

    The 2D scattering patterns and corresponding OOP and IP curves of B1:BO-4Cl and BTR:BO-4Cl blend films.

  • Figure 4

    The AFM height images (a, d), phase images (b, e), and TEM images (c, f) of B1:BO-4Cl- and BTR:BO-4Cl-based blend films with CB SVA treatment.

  • Table 1   Table 1 Photovoltaic data for recent reported high-efficency NFSM-OSCs (PCE > 13%)



    Voc (V)

    Jsc(mA cm−2)


    PCE (%)

    Certified PCE (%)

















































    This work

  • Table 2   Table 2 Detailed photovoltaic parameters of the B1:BO-4Cl-based and BTR:BO-4Cl-based NFSM-OSCs under simulated AM 1.5G (100 mW cm−2) illumination



    Voc (V)a

    Jsc(mA cm−2)a

    FF a

    PCE (%) a

    Jscb(mA cm−2)


    CB SVA

    0.83 (0.82±0.01)

    25.27 (24.81±0.40)

    0.73 (0.73±0.01)

    15.3 (14.9±0.2)


    CF SVA

    0.82 (0.82±0.01)

    24.34 (24.05±0.53)

    0.75 (0.74±0.01)

    15.0 (14.6±0.3)



    CB SVA

    0.83 (0.83±0.01)

    18.67 (17.91±0.75)

    0.67 (0.66±0.01)

    10.4 (9.9±0.5)


    CF SVA

    0.83 (0.83±0.01)

    18.93 (19.01±0.28)

    0.72 (0.69±0.02)

    11.3 (10.9±0.3)