Conjugated Molecules “Bridge”: Functional Ligand toward Highly Efficient and Long‐Term Stable Perovskite Solar Cell

• DOI: 10.1002/adfm.201808119
• Publication Date: 2019-02-04T08:20:22Z
• Authors: Hua Dong; Jun Xi; Lijian Zuo; Jingrui Li; Yingguo Yang; Dongdong Wang; Yue Yu; Lin Ma; Chenxin Ran; Weiyin Gao; Bo Jiao; Jie Xu; Ting Lei; Feijie Wei; Fang Yuan; Lin Zhang; Yifei Shi; Xun Hou; Zhaoxin Wu
• Keywords: Passivation

Abstract Interfacial ligand passivation engineering has recently been recognized as a promising avenue, contributing simultaneously to the optoelectronic characteristics and moisture/operation tolerance of perovskite solar cells. To further achieve win‐win situation both performance stability, an innovative conjugated aniline modifier (3‐phenyl‐2‐propen‐1‐amine; PPEA) is explored moderately tailor organolead halide perovskites films. Here, PPEA presents “quasi‐coplanar” rigid geometrical configuration distinct electron delocalization characteristics. After moderate treatment, stronger dipole capping layer can be formed at perovskite/transporting interface favorable banding alignment, thus enlarging built‐in potential promoting charge extraction. Meanwhile, cation coordinated surface grains/units form preferably ordered overlapping, not only passivating defects but also providing fast path for exchange. Benefiting from this, ≈21% efficiency PPEA‐modified cell obtained, accompanied by long‐term stability (maintaining 90.2% initial power conversion after 1000 h testing, 25 °C, 40 ± 10 humidity). This molecule “bridge” perform on larger scale, with 18.43% area 1.96 cm 2 .