A novel SnC/graphene heterostructure as an efficient host material for Li- and Na-ion batteries: computational insight

The rapid growth of technologies has influenced our daily lives in building efficient energy storage systems such as lithium-ion batteries (LIBs) for various electric automobiles and portable electronic devices. Graphite, the commercial anode material for LIBs, has several limitations including low lithium storage capacity (372 mAh g-1), low power rate capability, and sluggish charging for applications in grids and heavy electric vehicles. Herein, we propose a novel SnC/graphene heterostructure (SnC/G-H) as a potential anode material for LIBs and sodium-ion batteries, supported by first-principles calculations. The graphene layer in the SnC/G-H model provides high mechanical stability and electrical conductivity, enhancing device application and potentially solving the structural issues of the SnC monolayer. SnC/G-H serves as an excellent Li/Na host material, offering low average voltages (0.34-0.39 V), impressive Li/Na storage capacities of 870 mAh g-1 (exceeding those of pristine SnC and graphite), and minimal activation energy barriers of 0.043/0.079 eV, which promote efficient lithiation/delithiation and sodiation/desodiation processes. These enthralling findings indicate that the SnC/G-H could serve as an efficient host material for rechargeable LIBs and sodium-ion batteries.