Pseudohalide induced tunable electronic and excitonic properties in two-dimensional single-layer perovskite for photovoltaics and photoelectronic applications

作     者：Zhuo Xu Ming Chen Shengzhong(Frank)Liu Zhuo Xu;Ming Chen;Shengzhong (Frank) Liu

作者机构：Key Laboratory of Applied Surface and Colloid Chemistry National Ministry of Education Shaanxi Normal UniversityXi'an 710119 Shaanxi China Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Normal UniversityXi'an 710119 Shaanxi China Shaanxi Engineering Lab for Advanced Energy Technology Institute for Advanced Energy Materials Shaanxi Normal UniversityXi'an 710119 Shaanxi China School of Materials Science and Engineering Shaanxi Normal UniversityXi'an 710119 Shaanxi China iChEM Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China University of the Chinese Academy of SciencesBeijing 100039 China 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2019年第28卷第9期

页      面：106-113页

核心收录：

学科分类：0820[工学-石油与天然气工程] 0808[工学-电气工程] 07[理学] 0817[工学-化学工程与技术] 0807[工学-动力工程及工程热物理] 0827[工学-核科学与技术] 0703[理学-化学] 0702[理学-物理学] 

基　　金：funded by the National Key Research and Development Program of China (2017YFA0204800/2016YFA0202403) the Fundamental Research Funds for the Central Universities (2018CBLZ006) the National Natural Science Foundation of China (61604091 and 61674098) the 111 Project (B14041) the Changjiang Scholar and Innovative Research Team (IRT_14R33) the Chinese National 1000 Talents Plan program (1110010341) the China Postdoctoral Science foundation (2018M633455) the Fundamental Research Funds for the Central Universities (GK201903055) 

主　　题：Pseudohalide induced tunable electronic and excitonic properties in two-dimensional single-layer perovskite for photovoltaics and photoelectronic applications 

摘      要：Two-dimensional(2D) layered organic-inorganic hybrid perovskites have attracted much more attention for some applications than their three-dimensional(3D) perovskite counterparts due to their promising thermal and moisture stabilities.In particular, the 2D perovskite devices have shown better promise for optoelectronic applications.However, tunability of optoelectronic properties is often demanded to improve the device performance.Herein, we adopt a newly method to tune the electronic properties of 2D perovskite by introducing pseudohalide into the structure.In this work, we designed a pseudohalidesubstituted 2D perovskite by substituting the out-of-plane halide with pseudohalide and studied the electronic and excitonic properties of 2D-BA2MX4 and 2D-BA2MX2Ps2(M=Ge^(2+), Sn^(2+), and Pb^(2+);X=I;Ps=NCO, NCS, OCN, SCN, Se CN).We revealed the dependence of electronic properties including band gaps, composition of band edges, bonding characteristics, work functions, effective masses, and exciton binding energies on different pseudohalides substituted in 2D perovskite.Our results indicate that the substitution of pseudohalide in 2D perovskites is energetically favorable and can significantly affect the bonding characteristics as well as the CBM and VBM that often play major role in determining their performance in optoelectronic devices.It is expected that the pseudohalide substitution will be helpful in developing more advanced optoelectronic device based on 2D perovskite by optimizing band alignment and promoting charge extraction.