A novel two-dimensional monolayer MB4(M = Cr, Mo, W) MBenes as a high-performance anode material for Mg-ion batteries

Abstract

Rechargeable magnesium-ion batteries have garnered with great interest because abundant resources of magnesium and their potential for achieving high energy density. However, the realization of MIBs is hindered by the lack of appropriate electrode materials. In this study, the potential of 2D monolayers of CrB4, MoB4, and WB4 as anode materials for MIBs has been thoroughly studied using DFT calculations. Our preliminary investigations indicate that these monolayers demonstrate structural, mechanical, and thermodynamic stability. The significantly negative adsorption energy plays a vital role in stabilizing the surface adsorption of Mg ions, preventing clustering, and ensuring the stability of MIBs. The maximum TSC values are 3377 mA h g−1,2311 mA h g−1 and 1416 mA h g−1; and relatively low average OCV of 0.27 V,0.28 V and 0.19 V for CrB4, MoB4 and WB4 respectively, which is favoring to attaining high energy-density. The electronic properties revealed that as the Mg ion concentration increased, the electrical conductivity of the materials improved while maintaining their metallic nature, even after adsorption. However, the energy barriers were slightly higher and consistent with those of many common materials used as 2D anodes. Anticipated light shading of CrB4, MoB4, and WB4 was predicted to identify novel anode materials for MIBs.