Adsorption Energies of Lithium and Sodium Ions on Vanadium Disulphide: A DFT Study
Gloria I. Murila *
Computational and Theoretical Physics (CTHEP), Department of Physics, Masinde Muliro University of Science and Technology, Kenya.
George S. Manyali
Computational and Theoretical Physics (CTHEP), Department of Physics, Masinde Muliro University of Science and Technology, Kenya.
Henry B. Wafula
Computational and Theoretical Physics (CTHEP), Department of Physics, Masinde Muliro University of Science and Technology, Kenya.
*Author to whom correspondence should be addressed.
Abstract
Various energy sources are utilized at present with a challenge of energy storage in many cases. The existing rechargeable storage batteries which include sodium-ion and lithium-ion batteries have some limitations in their gravimetric capacities. Ab initio methods based on density functional theory (DFT) was used to investigate the adsorption of lithium ions and sodium ions on layered Vanadium disulphide. Metallic VS2 monolayer has a higher theoretical gravimetric capacity of 466mAh/g. This study showed that Sodium adsorbs on monolayer VS2 with lower adsorption energy of -2.00eV compared to Lithium (1.47eV) and it is more stable.
Keywords: Li-ion/Na-ion battery, adsorption energy