Layered SnSe nano-plates with excellent in-plane anisotropic properties of Raman spectrum and photo-responseElectronic supplementary information (ESI) available: EDS results of 2D SnSe nano-plates, the Raman spectra with different thickness, the schematic of polarized Raman system, a series of Raman spectra of SnSe flakes with different rotation angles measured with 633 nm and 785 nm lasers under parallel polarization configuration, polarized Raman properties with irregular morphology samples un

• Main Authors: Li, Xuan-Ze, Xia, Jing, Wang, Lei, Gu, Yi-Yi, Cheng, Hua-Qiu, Meng, Xiang-Min
• Format: Journal Article
• Language: English
• Published: 05.10.2017
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/c7nr05047j

In-plane anisotropy in optical, electronic and thermal properties of two-dimensional (2D) materials has attracted significant interest because of the huge potential applications for developing novel devices. In this work, outstanding angle-dependent Raman property of layered SnSe nano-plates is obtained via polarized Raman system and it is confirmed that the Raman polarization directions of two A g modes (130 cm −1 and 150 cm −1 ) are consistent with specific crystalline directions (zigzag direction or armchair direction) of SnSe flakes under parallel polarization configuration at home temperature and low temperature. Furthermore, the SnSe nano-plate devices show excellent angle-resolved photo-response at home temperature and low temperature (150 K) with a 90° cycle period and the polarized directions are also along zigzag direction and armchair direction, which is ascribed to the unique in-plane asymmetric crystal structure. These prominent in-plane anisotropic properties provide a precise and rapid method to determine the crystal orientation of SnSe nano-flakes and open up the new applications of 2D asymmetric structure materials. Orthorhombic SnSe nano-plates possess strong angle-resolved Raman property and obvious in-plane anisotropic photo-response, which could be used in creation of new-type devices and to supplement experimental results in study of anisotropic properties.