Theoretical Study on Sodium/Potassium Insertion Properties of Two-dimensional MgB2 Materials.

The development of anode materials with ideal conductivity, ultra-fast ion diffusion energy and large storage capacity is of great significance for rechargeable ion batteries, but also still challenging. In this work, the potential of two-dimensional MgB2 as an anode material of alkali metal (Na and K) ion batteries was explored via first-principles calculation. The results show that MgB2 has good structural stability and electrochemical performance. Specifically, Na and K ions can be stably adsorbed on two-dimensional MgB2, and the diffusion barrier is 0. 302 and 0. 172 eV, respectively, indicating its high performance in ultra-fast charging and discharging process. More importantly, the maximum storage capacities of two-dimensional MgB2 for sodium ion and potassium ion batteries are 1 167 and 584 mA ⋅ h/g, respectively. These results demonstrate that two-dimensional MgB2 can be used as a promising anode material for sodium ion and potassium ion batteries. [ABSTRACT FROM AUTHOR]