title: Growth of Single-Crystalline Cadmium Iodide Nanoplates, CdI2/MoS2(WS2, WSe2) van der Waals Heterostructures, and Patterned Arrays.
abstract: Two-dimensional layered materials (2DLMs) have attracted considerable recent interest for their layer-number-dependent physical and chemical properties, as well as potential technological opportunities. Here we report the synthesis of two-dimensional layered cadmium iodide (CdI2) nanoplates using a vapor transport and deposition approach. Optical microscopy and scanning electron microscopy studies show that the resulting CdI2nanoplates predominantly adopt hexagonal and triangular morphologies with a lateral dimension of ∼2-10 μm. Atomic force microscopy studies show that the resulting nanoplates exhibit a thickness in the range of 5-220 nm with a relatively smooth surface. X-ray diffraction studies reveal highly crystalline CdI2in hexagonal phase, which is also confirmed by the characteristic Raman Agmode at 110 cm-1. High-resolution transmission electron microscopy and selected area electron diffraction reveal that the resulting CdI2nanoplates are single crystals. Taking a step further, we show the CdI2nanoplates were readily grown on other 2DLMs (e.g., WS2, WSe2, MoS2), forming diverse van der Waals heterostructures. Using prepatterned WS2monolayer square arrays as the nucleation and growth templates, we also show that regular arrays of CdI2/WS2vertical heterostructures can be prepared. The synthesis of the CdI2nanoplates, heterostructures, and heterostructure arrays offers a valuable material system for 2D materials science and technology.
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, China.
authors.forename: Ruoqi
authors.initials: R
authors.lastname: Ai
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, China.
authors.forename: Xun
authors.initials: X
authors.lastname: Guan
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, China.
authors.forename: Kangkang
authors.initials: K
authors.lastname: Yao
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Chen
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, China.
authors.forename: Zhengwei
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, China.
authors.forename: Xidong
authors.initials: X
authors.lastname: Duan
authors.affiliation: Department of Chemistry and Biochemistry, California NanoSystems Institute, University of California, Los Angeles , Los Angeles, California 90095, United States.
authors.forename: Xiangfeng
authors.identifier: 0000-0002-4321-6288
authors.initials: X
authors.lastname: Duan
keywords: 2D materials; CdI2 nanoplates; patterned array; transition metal dichalcogenides; van der Waals heterostructures