Potential application of kekulene nanoring in the Li-ion batteries: DFT studies

Abstract

We explored the potential application of kekulene nanoring in the anode of Li-ion batteries using B3LYP-gCP-D3/6-31G* model chemistry. Molecular electrostatic potential analysis indicates a current density alternatively on the kekulene hexagons, being compatible with the Clar’s aromaticity model. Li atom or cation prefer deposit above the aromatic rings with adsorption energies of −53.4 or −21.4 kcal/mol. The maximum deformation energy upon the Li/Li+ adsorption is 5.2 kcal/mol, demonstrating that the kekulene nanoring preserves its initial geometry during the adsorption process. The Li cation has to overwhelm a small maximum energy barrier of 4.7 kcal/mol to migrate in the kekulene surface, indicating an ultra-high ion mobility. The specific capacity and cell voltage are predicted to be 504.6 mAh/g and 1.38 V, respectively. Thus, the large cell voltage, high ion mobility, and great storage capacity make the kekulene a plausible candidate for application as an anode material of Li-ion batteries.