title: m-Methoxy Substituents in a Tetraphenylethylene-Based Hole-Transport Material for Efficient Perovskite Solar Cells.
abstract: Three tetrapheynlethylene derivatives (N,N-di(4-methoxyphenyl)aminophenyl-substituted tetraphenylethylene; TPE-4DPA) with different methoxy positions (pp-, pm-, and po-) have been synthesized and characterized. The methoxy groups can control the oxidation potential of the materials, and the electronic properties of the derivatives were affected by the position of the methoxy substituents. These compounds were synthesized in a facile and cost-effective way, and were applied as hole-transport materials in perovskite solar cells. The corresponding cell performances were compared with respect to their structure modifications, and it was found that the derivative with m-OMe substituents showed the highest power conversion efficiency (PCE) of 15.4 %, with a Jscvalue of 20.04 mA cm-2, a Vocvalue of 1.07 V, and a fill factor (FF) value of 0.72, which is higher than the p-OMe and o-OMe substituents. Moreover, the PCE of pm-TPE-4DPA is comparable with that of the state-of-the-art 2,2',7,7'-tetrakis(N,N'-di-p-methoxyphenylamine)-9,9'-spirobifluorene under identical conditions.
authors.affiliation: Chongqing Key Laboratory for Advanced Materials, and Technologies of Clean Energy, Faculty of Materials & Energy, Southwest University, Chongqing, 400715, P.R. China. feiwu610@swu.edu.cn.
authors.forename: Fei
authors.initials: F
authors.lastname: Wu
authors.affiliation: Chongqing Key Laboratory for Advanced Materials, and Technologies of Clean Energy, Faculty of Materials & Energy, Southwest University, Chongqing, 400715, P.R. China.
authors.forename: Jianlin
authors.initials: J
authors.lastname: Liu
authors.affiliation: Chongqing Key Laboratory for Advanced Materials, and Technologies of Clean Energy, Faculty of Materials & Energy, Southwest University, Chongqing, 400715, P.R. China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.affiliation: Chongqing Key Laboratory for Advanced Materials, and Technologies of Clean Energy, Faculty of Materials & Energy, Southwest University, Chongqing, 400715, P.R. China.
authors.forename: Qunliang
authors.initials: Q
authors.lastname: Song
authors.affiliation: Chongqing Key Laboratory for Advanced Materials, and Technologies of Clean Energy, Faculty of Materials & Energy, Southwest University, Chongqing, 400715, P.R. China. lnzhu@swu.edu.cn.
authors.forename: Linna
authors.initials: L
authors.lastname: Zhu
keywords: charge transfer; electrochemistry; methoxy groups; perovskite phases; structure-activity relationships