Synthesis and thermoelectric properties of Bi-doped SnSe thin films

• 作 者: Jun Pang Xi Zhang Limeng Shen Jiayin Xu Ya Nie Gang Xiang
• 机 构: College of Physics,Sichuan University,Chengdu 610064,China
• 出 处: 中国物理B（英文版）
• 发表日期: 2021年11期
• 关键词: SnSe thin films Bi doping thermoelectric properties Seebeck coefficient

Bi doped n-type SnSe thin films were prepared by chemical vapor deposition (CVD) and their structure and thermo-electric properties were studied.The x-ray diffraction patterns,x-ray photoelectron spectroscopy,and microscopic images show that the prepared SnSe thin films were composed of pure SnSe crystals.The Seebeck coefficients of the Bi-doped SnSe were greatly improved compared to that of undoped SnSe thin films.Specifically,Sn0.99Bi0.01Se thin film exhibited a Seebeck coefficient of-905.8 μV·K-1 at 600 K,much higher than 285.5 μV·K-1 of undoped SnSe thin film.Further first-principles calculations reveal that the enhancement of the thermoelectric properties can be explained mainly by the Fermi level lifting and the carrier pockets increasing near the Fermi level due to Bi doping in the SnSe samples.Our results suggest the potentials of the Bi-doped SnSe thin films in thermoelectric applications.