Efficient charge transfer in WS2/WxMo1-xS2 heterostructure empowered by energy level hybridization

作     者：Xuhong AN Yehui ZHANG Yuanfang YU Weiwei ZHAO Yutian YANG Xianghong NIU Xuan LUO Junpeng LU Jinlan WANG Zhenhua NI 

作者机构：School of Physics and Key Laboratory of MESMS of the Ministry of EducationSoutheast University New Energy Technology Engineering Laboratory of Jiangsu Province and School of ScienceNanjing University of Posts and Telecommunications Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences 

出 版 物：《Science China(Information Sciences)》 (中国科学:信息科学(英文版))

年 卷 期：2023年第66卷第2期

页      面：219-226页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0804[工学-仪器科学与技术] 0703[理学-化学] 0702[理学-物理学] 

基　　金：supported by National Key Research and Development Program of China (Grant Nos. 2019YFA0308000, 2017YFA0205700, 2017YFA0204800) National Natural Science Foundation of China (Grant Nos. 61927808, 61774034, 21525311, 91963130, 62174026) Jiangsu Province Basic Research Plan (Grant No. BK20170694) Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB30000000) Fundamental Research Funds for the Central Universities 

主　　题：van der Waals heterostructure band offset hybridization strength charge transfer photoluminescence quenching 

摘      要：Photoinduced charge transfer(CT) is decisive to the efficiency and speed of photoelectric conversion in two-dimensional(2D) van der Waals(vd Ws) heterostructures. Generally, CT rate enhancement is realized by increasing the band offset(BO). In this study, we propose that a fast and efficient CT can be realized via strong hybridization of energy levels in 2D vd Ws heterostructures with minimal BO. Firstprinciples calculations reveal that the smallest energy difference between conduction-band edges and minimal BO in the WS2/WxMo1-xS2(x = 0.78) heterostructure yields the strong hybridization of energy levels and then results in ultrafast CT(2.7 ps). Experimental results agree with theoretical calculations. The photoluminescence of WS2is quenched in the WS2/WxMo1-xS2(x = 0.78) heterostructure, attributable to the strong hybridization-induced fast and efficient CT. This study provides insights into the mechanism of CT in heterostructures and offers new strategies to create superior optoelectronic devices with fast and efficient photoelectric conversion.