2D SnC sheet with a small strain is a promising Li host material for Li-ion batteries

Abstract

The next-generation renewable energy technology demands electrode materials with suitable structural, electronic, mechanical, and electrochemical properties. Employing DFT calculations, monolayer SnC has been investigated for the anodic applications of Li-ion batteries. The proposed SnC monolayer is mechanically, dynamically, and thermally stable based on theoretical calculations. These important features ensure the experimental synthesis of 2D SnC. The pristine 2D SnC exhibits semiconducting nature with indirect band gap. With the application of strain effect, the electronic properties and binding energies of Li ions on SnC are modulated. At the tensile strain of 6%, the material becomes to be metallic. Furthermore, loading a small amount of Li, the electronic conductivity can be improved. As a Li hosting material, 2D SnC displays a very low average open circuit voltage (0.44 V) with a maximum theoretical capacity of 410 mAhg−1 under the tensile strain of 6%. The very low diffusion barriers about 0.09∼0.17 eV on the SnC surface with the applied stain leads to fast lithiation and delithiation cycles. Our results specify that the strain engineered 2D SnC could be a favorable Li host material for LIBs.