Density Functional Theory Calculations for the Evaluation of FePS3 as a Promising Anode for Mg Ion Batteries

Abstract

FePS3, a classical 2D layered material with transition metal phosphorous trichalcogenides, was investigated as an anode material for Mg ion batteries. We used density functional theory to calculate the Mg storage properties of FePS3, such as Mg adsorption energy, theoretical specific capacity, average voltage, diffusion energy barriers, volume change, and electronic conductivity. The theoretical specific capacity of the FePS3 monolayer is 585.6 mA h/g with a relatively low average voltage of 0.483 V (vs. Mg/Mg2+), which is favorable to a high energy density. The slight change in volume and good electronic conductivity of bulk FePS3 are beneficial to electrode stability during cycling.