Enhanced lithium adsorption/diffusion and improved Li capacity on SnS2 nanoribbons: A computational investigation

Density functional theory computations were performed to investigate the adsorption and diffusion properties of lithium (Li) on tin disulfides nanosheets and its derived nanoribbons (NRs), in comparison with SnS2 bulk in 1T phase. The Li adsorption energies and migration barriers are comparable in SnS2 bulk and bilayer, and Li adsorbed at the octahedral sites has the highest binding energy in both SnS2 bulk and bilayer. Reducing the dimension of SnS2 to monolayer significantly lowers the Li diffusion barrier while keeping a considerable binding energy, and lithium favors the hollow sites which corresponding to the octahedral sites in bulk phase. Due to the edge effect, SnS(2)NRs gain an enhanced Li binding strength, increased Li mobility, and improved Li capacity. Thus, SnS2 NRs are a promising candidate for anode materials of Li-ion batteries with a high power density and fast charge/discharge rates.