Tetrachloroaluminate Ion on Graphene Quantum Dots: Towards the Design of Cathode for Aluminum-ion Battery

Abstract

The adsorption of tetrachloroaluminate, AlCl4-, on Graphene Quantum Dot (GQD) were studied using Density Functional Theory (DFT). Coronene (C24H12) and circumcoronene (C54H18) were used as the model of GQDs. All possible adsorption sites which include hollow, bridge, and on-top as well as three possible standing positions of AlCl4- were investigated. AlCl4- can be adsorbed on the GQD surface with the adsorption energy of -2.35 to -2.83 eV for the charging condition. The adsorption energy of AlCl4- during charging is around 10 times that during discharging. From our study, GQDs can be used as cathode material for Aluminium-ion Battery (AIB) providing higher voltage than graphite. The theoretical voltage for coronene and circumcoronene was found to be 4.3V and 4.0 V, respectively.