First-principles computational study of Janus van der Waals layered VSiGeN₄ as anode material for Li-ion battery

An emerging class of two-dimensional Janus materials has received increasing attention due to their unique non-reflective symmetry crystal structure. In order to find a potential anode material in this two-dimensional Janus materials, the kinetic and thermodynamic stability of VSi2N4, VGe2N4, VSiGeN4 structures were investigated. It is discovered that the stability of the VSiGeN4 structure is significantly better than VGe2N4 and is essentially similar to VSi2N4. Additionally, the addition of Ge atoms can significantly boost conductive performance and enhance charge and discharge rates. The usage of VSiGeN4 as an appropriate commercial anode material was demonstrated by its capacity of up to 1291.6 mAh/g and the relevant range of OCV fluctuations. As mentioned above, 2D VSiGeN4 will be a promising anode material for Li ion battery.