On the utility of C24 fullerene framework for Li-ion batteries: Quantum chemical analysis

Abstract

The potential application of carbonaceous C24 nanocluster framework as an anode in Li-ion batteries (LIBs) is investigated using density functional theory calculations. We find that this fullerene unexpectedly gives an imaginary cell voltage and cannot be used as an anode in LIBs. Here, we explain the origin of this unusual behavior and introduce a strategy to make it suitable for anode materials. We show that there is no energy barrier for Li+ diffusion through two neighboring hydrogenated C24 fullerenes. The percentage of Hartree Fock (HF) exchange of density functionals reversely affects the adsorption energies of Li and Li+, so that it is decreased and increased by increasing %HF exchange, respectively. Also, a linear relationship between %HF and HOMO or LUMO level of the studied systems is predicted.