Quantum capacitance of graphene-like/graphene heterostructures for supercapacitor electrodes

The charge storage capacity, quantum capacitance, and atomic structures of transition-metal doped graphene-like/graphene heterostructures were studied by density functional theory (DFT). The impact of transition-metal (TM) doping (Ni, Co, Fe, Mn, Cr, V, Ti, and Sc) on the capacitance capacity of silicene/graphene, phosphorene/graphene, germanene/graphene, WSe2/graphene heterostructures was also examined. The findings showed that doping was more useful compared to vacancy defects to enhance the quantum capacitance of heterostructures. The Sc-doped WSe2/graphene exhibited the highest quantum capacitance (838.24 μF/cm2), which is the most promising positive electrode material for supercapacitors. The findings were supposed to provide the theoretical foundation to produce high-capacitance supercapacitors.