title: Composition-Modulated Two-Dimensional Semiconductor Lateral Heterostructures via Layer-Selected Atomic Substitution.
abstract: Composition-controlled growth of two-dimensional layered semiconductor heterostructures is crucially important for their applications in multifunctional integrated photonics and optoelectronics devices. Here, we report the realization of composition completely modulated layered semiconductor MoS2-MoS2(1-x)Se2x(0 < x < 1) lateral heterostructures via the controlled layer-selected atomic substitution of pregrown stacking MoS2, with a bilayer located at the center of a monolayer. Through controlling the reaction time, S at the monolayer MoS2at the peripheral area can be selectively substituted by Se atoms at different levels, while the bilayer region at the center retains the original composition. Microstructure characterizations demonstrated the formation of lateral heterostructures with a sharp interface, with the composition at the monolayer area gradually modulated from MoS2to MoSe2and having high-quality crystallization at both the monolayer and the bilayer areas. Photoluminescence and Raman mapping studies exhibit the tunable optical properties only at the monolayer region of the as-grown heterostructures, which further demonstrates the realization of high-quality composition/bandgap modulated lateral heterostructures. This work offers an interesting and easy route for the development of high-quality layered semiconductor heterostructures for potential broad applications in integrated nanoelectronic and optoelectronic devices.
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Honglai
authors.initials: H
authors.lastname: Li
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Xueping
authors.initials: X
authors.lastname: Wu
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Liu
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Biyuan
authors.initials: B
authors.lastname: Zheng
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Qinglin
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Zhu
authors.affiliation: College of Materials Science and Engineering, Chongqing University , Chongqing 400030, P. R. China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wei
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Zhuang
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhou
authors.affiliation: College of Materials Science and Engineering, Chongqing University , Chongqing 400030, P. R. China.
authors.forename: Wenxin
authors.initials: W
authors.lastname: Tang
authors.affiliation: Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095, United States.
authors.forename: Xiangfeng
authors.identifier: 0000-0002-4321-6288
authors.initials: X
authors.lastname: Duan
authors.affiliation: Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Anlian
authors.identifier: 0000-0003-3335-3067
authors.initials: A
authors.lastname: Pan
keywords: atomic substitution; lateral heterostructures; layered semiconductor; transition-metal dichalcogenides; tunable compositions