Journal of Inorganic Materials ›› 2023, Vol. 38 ›› Issue (9): 1097-1102.DOI: 10.15541/jim20220777

Special Issue: 【能源环境】钙钛矿(202310) 【能源环境】太阳能电池(202310)

• RESEARCH ARTICLE • Previous Articles     Next Articles

Application of Single-molecule Liquid Crystal Additives in CH(NH2)2PbI3 Perovskite Solar Cells

HAN Xu(), YAO Hengda, LYU Mei, LU Hongbo, ZHU Jun()   

  1. Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronics Engineering, Hefei University of Technology, Hefei 230009, China
  • Received:2022-12-29 Revised:2023-03-08 Published:2023-09-20 Online:2023-04-11
  • Contact: ZHU Jun, professor. E-mail: jzhu@hfut.edu.cn
  • About author:HAN Xu (1999-), male, Master candidate. E-mail: hanxu0050@163.com
  • Supported by:
    National Key R&D Program of China(2019YFE0101300);Fundamental Research Funds for the Central Universities(JZ2022HGTA0327);Fundamental Research Funds for the Central Universities(JZ2021HGQA0264)

Abstract:

Solution-processed perovskite films usually contain a large quantity of grain boundaries, which decrease the film crystalline quality and introduce severe defect recombination, hindering performance of the devices based on them. Therefore, preparation of high-quality films to achieve high power conversion efficiencies remains a great challenge for perovskite solar cells. Due to high abilities of self-assembly and morphology-tuning for liquid crystal molecules, a single-molecule liquid crystal 4-cyano-4′-pentyl biphenyl (5CB) was employed as additive in CH(NH2)2PbI3 (FAPbI3) precursor solution to increase the perovskite grain size and decrease the grain boundaries. In addition, the cyano group in 5CB passivates the uncoordinated Pb2+ in the perovskite films, which reduces the trap density concentration and inhibits the nonradiative recombination. The resulting perovskite solar cells with 0.2 mg/mL 5CB in the precursor achieve an efficient power conversion efficiency of 21.27% with an open circuit voltage of 1.086 V, a current density of 24.17 mA/cm2, and a fill factor of 80.96%. In conclusion, introducing single-molecule liquid crystal as additive is a facile and efficient strategy for improving the performance of FAPbI3 solar cells.

Key words: perovskite solar cell, FAPbI3, liquid crystal, 4-cyano-4′-n-pentyl-biphenly, defect passivation

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