Piezoelectricity of Janus Sb2Se2Te monolayers: A first-principles study
Jian Qiu, Hui Li, Xianping Chen, Bao Zhu, Haojie Guo, Fusheng Zhang, Zhaogui Ding, Lei Lang, Jiabing Yu, Jiading Bao
Abstract
There are few studies on two-dimensional (2D) piezoelectric materials with polyatomic thickness at the present stage. The 2D materials with a thickness of 5 atoms were investigated on the piezoelectric effect of Sb2Se2Te, Sb2Te2Se, and three structures of SbAsSe2Te monolayers. The calculated piezoelectric coefficient d31 of Sb2Te2Se is 1.72 pm/V and is higher than that of the other four 2D piezoelectric materials. Compared with other 2D piezoelectric materials, the out-of-plane piezoelectric properties of 2D Janus Sb2Te2Se show great advantages. Density functional perturbation theory was employed to calculate the piezoelectric tensors. The charge density distribution was calculated to explain the polarization and chemical bonds. The electrostatic potential energy was calculated to reveal the polarization phenomenon. Our works imply that 2D Janus Sb2Te2Se monolayer have potential applications in flexible electronics and piezoelectric devices.