title: Exciton localization in solution-processed organolead trihalide perovskites.
abstract: Organolead trihalide perovskites have attracted great attention due to the stunning advances in both photovoltaic and light-emitting devices. However, the photophysical properties, especially the recombination dynamics of photogenerated carriers, of this class of materials are controversial. Here we report that under an excitation level close to the working regime of solar cells, the recombination of photogenerated carriers in solution-processed methylammonium-lead-halide films is dominated by excitons weakly localized in band tail states. This scenario is evidenced by experiments of spectral-dependent luminescence decay, excitation density-dependent luminescence and frequency-dependent terahertz photoconductivity. The exciton localization effect is found to be general for several solution-processed hybrid perovskite films prepared by different methods. Our results provide insights into the charge transport and recombination mechanism in perovskite films and help to unravel their potential for high-performance optoelectronic devices.
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Haiping
authors.initials: H
authors.lastname: He
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Junjie
authors.initials: J
authors.lastname: Si
authors.affiliation: Center for Chemistry of High-Performance and Novel Materials and State Key Laboratory of Silicon Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
authors.forename: Yizheng
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Key Laboratory of Flexible Electronics (KLOFE) &Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, China.
authors.forename: Nana
authors.initials: N
authors.lastname: Wang
authors.affiliation: Key Laboratory of Flexible Electronics (KLOFE) &Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, China.
authors.forename: Jianpu
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Physics, Capital Normal University, Beijing Key Lab for Metamaterials and Devices, and Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Beijing 100048, China.
authors.forename: Jingwen
authors.initials: J
authors.lastname: He
authors.affiliation: Department of Physics, Capital Normal University, Beijing Key Lab for Metamaterials and Devices, and Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Beijing 100048, China.
authors.forename: Xinke
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Physics, Capital Normal University, Beijing Key Lab for Metamaterials and Devices, and Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Beijing 100048, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Zhizhen
authors.initials: Z
authors.lastname: Ye