In-situ micro-Raman study of SnSe single crystals under atmosphere: Effect of laser power and temperature

Xiangnan Gong; Yingru Wang; Qiongmei Hong; Jie Liu; Chuanyao Yang; Hanjun Zou; Yang Zhou; Dejun Huang; Hong Wu; Zizhen Zhou; Bin Zhang; Xiaoyuan Zhou

doi:10.1016/j.saa.2021.120375

In-situ micro-Raman study of SnSe single crystals under atmosphere: Effect of laser power and temperature

Spectrochim Acta A Mol Biomol Spectrosc. 2022 Jan 15:265:120375. doi: 10.1016/j.saa.2021.120375. Epub 2021 Sep 10.

Authors

Xiangnan Gong¹, Yingru Wang², Qiongmei Hong³, Jie Liu⁴, Chuanyao Yang⁴, Hanjun Zou⁴, Yang Zhou⁴, Dejun Huang⁵, Hong Wu⁶, Zizhen Zhou⁷, Bin Zhang⁸, Xiaoyuan Zhou⁹

Affiliations

¹ Analytical and Testing Center, Chongqing University, Chongqing 401331, China. Electronic address: xiangnan.gong@cqu.edu.cn.
² College of Chemistry and Chemical Engineering, Chongqing University 401331, China.
³ College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China.
⁴ Analytical and Testing Center, Chongqing University, Chongqing 401331, China.
⁵ Malvern Panalytical (China), Shanghai 200233, China.
⁶ School of Science, Chongqing University of Posts and Telecommunications, Chongqing 400065, China.
⁷ College of Physics, Chongqing University, Chongqing 401331, China.
⁸ Analytical and Testing Center, Chongqing University, Chongqing 401331, China. Electronic address: xinyun2017@cqu.edu.cn.
⁹ Analytical and Testing Center, Chongqing University, Chongqing 401331, China; College of Physics, Chongqing University, Chongqing 401331, China. Electronic address: xiaoyuan2013@cqu.edu.cn.

PMID: 34536888
DOI: 10.1016/j.saa.2021.120375

Abstract

Single crystal of tin selenide (SnSe) was studied by micro-Raman spectroscopy under atmosphere conditions. The effect of varying the incident laser power on the sample up to 2 mW was analyzed. The Raman spectra showed that the number of all vibrational modes have not decreased or increased, but all peaks red-shifted and softened obviously as the laser power increased to the threshold value. The temperature-dependent micro-Raman study of the single crystal was carried out for illustrating thermal effect due to the high incident laser power. A new SnSe₂ phase appeared at high temperature without vacuum and become the dominant phase at the surface of the crystal gradually because of oxidation. Detecting few amounts of SnSe₂ crystals on the surface of single crystal shows the high sensitivity of Raman spectroscopy. High resolution transmission electron microscopy (HRTEM) was also used to confirm that the newly generated SnSe₂ phase is precipitated by SnSe under high temperature oxidation conditions. To study the Raman spectra of low thermal conductivity materials under high temperature and non-vacuum conditions, lower incident laser power should be used to avoid the influence of additional thermal effects.

Keywords: Laser power; Raman spectroscopy; Single crystal SnSe; TEM technology; Temperature.