First-principles calculations of bulk XTe2 (X = Mo, W) as anode materials for Ca ion battery.

Abstract

Transition metal chalcogenides are excellent anode materials for calcium ion batteries (CIBs). In this study, the structural stability, electronic structure, and diffusion barrier of bulk XTe2 (X = Mo, W) were studied by first-principles calculations within the framework of density functional theory. The density of states analysis shows the metal behavior of XTe2 (X = Mo, W) during calcification. The voltage ranges of CayMoTe2 and CayWTe2 are 1.53-0.45 V and 1.48-0.41 V (y = 0-5), respectively. The diffusion barrier of Ca+ through XTe2 indicates that the compressive strain promotes the diffusion of calcium through XTe2. XTe2 is considered to be a promising electrode material for CIBs. In this paper, the transition metal chalcogenides model is constructed by Material Studio 8.0, and the first-principles calculation is carried out by CASTEP module.