文献类型：期刊文献

英文题名：A Band-Edge Potential Gradient Heterostructure to Enhance Electron Extraction Efficiency of the Electron Transport Layer in High-Performance Perovskite Solar Cells

作者：Hou, Yu[1,2];Chen, Xiao[1];Yang, Shuang[1];Li, Chunzhong[1];Zhao, Huijun[2];Yang, Hua Gui[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Minist Educ, Key Lab Ultrafine Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China;[2]Griffith Univ, Ctr Clean Environm & Energy, Gold Coast Campus, Nathan, Qld 4222, Australia

年份：2017

卷号：27

期号：27

外文期刊名：ADVANCED FUNCTIONAL MATERIALS

收录：;EI(收录号：20172203699144);WOS:【SCI-EXPANDED(收录号:WOS:000405926800009)】；

基金：Y.H. and X.C. contributed equally to this work. This work was financially supported by the National Natural Science Foundation of China (21373083, 21573068, and 51602103), the SRF for ROCS, SEM, SRFDP, the Fundamental Research Funds for the Central Universities (WD1514301), the China Postdoctoral Science Foundation Funded Project (2015M581547 and 2016T90342), the "Chen Guang" Project supported by the Shanghai Municipal Education Commission and the Shanghai Education Development Foundation (15CG26), the Major Research plan of the National Natural Science Foundation of China (91534202), the 111 Project (B14018), the Shanghai Sailing Program (16YF1402100), and the ARC Discovery Projects (DP150103775).

语种：英文

外文关键词：electron transport layers; gradient heterojunctions; interface engineering; perovskite solar cells

摘要：As the key component in efficient perovskite solar cells, the electron transport layer (ETL) can selectively collect photogenerated charge carriers produced in perovskite absorbers and prevent the recombination of carriers at interfaces, thus ensuring a high power conversion efficiency. Compared with the conventional single-or dual-layered ETLs, a gradient heterojunction (GHJ) strategy is more attractive to facilitate charge separation because the potential gradient created at an appropriately structured heterojunction can act as a driving force to regulate the electron transport toward a desired direction. Here, a SnO2/TiO2 GHJ interlayer configuration inside the ETL is reported to simultaneously achieve effective extraction and efficient transport of photoelectrons. With such an interlayer configuration, the GHJs formed at the perovskite/ETL interface act collectively to extract photogenerated electrons from the perovskite layer, while GHJs formed at the boundaries of the interconnected SnO2 and TiO2 networks throughout the entire ETL layer can extract electron from the slow electron mobility TiO2 network to the high electron mobility SnO2 network. Devices based on GHJ ETL exhibit a champion power conversion efficiency of 18.08%, which is significantly higher than that obtained from the compact TiO2 ETL constructed under the comparable conditions.