Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Oct;9(30):e2203606.
doi: 10.1002/advs.202203606. Epub 2022 Aug 23.

Over 19.2% Efficiency of Organic Solar Cells Enabled by Precisely Tuning the Charge Transfer State Via Donor Alloy Strategy

Jinhua Gao  1 , Na Yu  2 , Zhihao Chen  3 , Yanan Wei  1 , Congqi Li  1 , Tianhua Liu  1 , Xiaobin Gu  1 , Jianqi Zhang  4 , Zhixiang Wei  4 , Zheng Tang  2 , Xiaotao Hao  3 , Fujun Zhang  5 , Xin Zhang  1 , Hui Huang  1
Affiliations

Over 19.2% Efficiency of Organic Solar Cells Enabled by Precisely Tuning the Charge Transfer State Via Donor Alloy Strategy

Jinhua Gao et al. Adv Sci (Weinh). 2022 Oct.

Abstract

The large energy loss (Eloss ) is one of the main obstacles to further improve the photovoltaic performance of organic solar cells (OSCs), which is closely related to the charge transfer (CT) state. Herein, ternary donor alloy strategy is used to precisely tune the energy of CT state (ECT ) and thus the Eloss for boosting the efficiency of OSCs. The elevated ECT in the ternary OSCs reduce the energy loss for charge generation (ΔECT ), and promote the hybridization between localized excitation state and CT state to reduce the nonradiative energy loss (ΔEnonrad ). Together with the optimal morphology, the ternary OSCs afford an impressive power conversion efficiency of 19.22% with a significantly improved open-circuit voltage (Voc ) of 0.910 V without sacrificing short-cicuit density (Jsc ) and fill factor (FF) in comparison to the binary ones. This contribution reveals that precisely tuning the ECT via donor alloy strategy is an efficient way to minimize Eloss and improve the photovoltaic performance of OSCs.

Keywords: charge transfer state; donor alloy strategy; energy loss; organic solar cells.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
a) Chemical structures of PM6, D18‐Cl and L8‐BO. b) Normalized absorption spectra of neat films. c) Contact angle images of neat PM6 and D18‐Cl films. d) DSC curves of PM6:D18‐Cl blend with various D18‐Cl contents in the heating process.
Figure 2
Figure 2
a) J–V curves of the binary and ternary OSCs. b) The V oc values of efficient OSCs with PCEs of over 18% (Detailed photovoltaic parameters are summarized in Table S3, Supporting Information). c) EQE spectra of the binary and ternary OSCs. d–f) The sEQE and EL spectra of the binary and ternary OSCs. g) Orbital energy diagram of PM6:D18‐Cl:L8‐BO ternary system with alloying donor. h) Illustration of the potential energy surfaces for ground state (GS), LE state and CT state. knrCT−LEandknrLE−CT are the nonradiative transitions from CT/LE state to LE/CT state. krLE, krCT, or knrLE, knrCT is the radiative or nonradiative transitions from the LE/CT state to the ground state. i) EQEEL curves of the binary and optimal ternary OSCs.
Figure 3
Figure 3
a–c) 2D TA color plots of binary and ternary blend films. d) The decay traces of donor and acceptor in binary and ternary blend films, monitored at 595 and 725 nm, respectively. e) The GSB kinetics of donor probed at 595 nm in binary and ternary blend films. f) J ph–V eff curves of the binary and ternary OSCs.
Figure 4
Figure 4
a) V OC and J SC of the OSCs dependence on P light. b) TPC curves and c) TPV curves of the binary and ternary OSCs.
Figure 5
Figure 5
a) 2D GIWAXS patterns and b) 1D line‐cut profiles of PM6:D18‐Cl:L8‐BO films with various D18‐Cl contents.
See this image and copyright information in PMC

References

    1. Park S., Heo S. W., Lee W., Inoue D., Jiang Z., Yu K., Jinno H., Hashizume D., Sekino M., Yokota T., Fukuda K., Tajima K., Someya T., Nature 2018, 561, 516. - PubMed
    1. Cheng P., Li G., Zhan X., Yang Y., Nat. Photonics 2018, 12, 131.
    1. Cheng Y., Huang B., Huang X., Zhang L., Kim S., Xie Q., Liu C., Heumuller T., Liu Z., Zhang Y., Wu F., Yang C., Brabec C. J., Chen Y., Chen L., Angew. Chem., Int. Ed. 2022, 61, 202200329. - PubMed
    1. Chen Z., Song W., Yu K., Ge J., Zhang J., Xie L., Peng R., Ge Z., Joule 2021, 5, 2395.
    1. Qian D., Zheng Z., Yao H., Tress W., Hopper T. R., Chen S., Li S., Liu J., Chen S., Zhang J., Liu X. K., Gao B., Ouyang L., Jin Y., Pozina G., Buyanova I. A., Chen W. M., Inganas O., Coropceanu V., Bredas J. L., Yan H., Hou J., Zhang F., Bakulin A. A., Gao F., Nat. Mater. 2018, 17, 703. - PubMed