Magnesiation of bare and halides encapsulated B40 fullerenes for their potential application as promising anode materials for Mg-ion batteries

Abstract

Density functional theory (DFT) calculations using the PBE0-D3 functional and the 6–31 + G(d) basis set were carried out to determine the potential application of newly experimentally observed B40 fullerene for the anode electrode for Mg-ion batteries (MIBs). Calculated results suggest the bare B40 fullerene as a promising anode material with remarkable average open-circuit voltage of 5.5 V and storage capacity of 744 mAhg−1. Furthermore, it was found that the halides (F–, Cl–, and Br–) encapsulation inside B40 fullerene with both remarkable thermodynamic and kinetic stability can markedly enhance average open-circuit voltage up to 8.8 V. This value is remarkable compared with previous reports in the literature. Additionally, we re-calculated the average open-circuit voltage with the TPPSh, M06-2X, and B3LYP-D3 functionals along with the 6–311 + G(d) basis set. The results are similar to those values obtained at PBE0-D3/6–31 + G(d). The nature of Mg and Mg2+ interaction with bare and halides encapsulated B40 were also analyzed through the quantum theory of atoms in molecules (QTAM). The current results in this study might open new windows for the design of promising boron-based anode materials for MIBs.