Envisaging the quantum capacitance in modified monolayer silicon carbide

Versatile properties of electric double layer supercapacitors such as high output power, safety, high efficiency and durability have gained so much attention for use as energy storage systems. On the other hand their applications have been limited due to an attributed low energy density. It therefore necessary to improve their quantum capacitance in an effective way. In this research, we have investigated the effects of monovacancy and divacancy, nonmetal doping and adsorption of transition metals (Co, Cu, Ni and Zn) on the quantum capacitance of monolayer SiC using first principles calculations. The calculated results show that, incorporating boron in defected 2D-SiC significantly improves the C_Q of monolayer silicene. The corresponding C_Q values for 1st, 2nd, 3rd and 4th boron substitutions are 59.4, 82.3, 110.2 and 79.4 µF/cm² respectively, which were found to be good for anode materials for supercapacitors. Moreover, transitions metals adsorbed monolayer SiC were also found to significantly improve the CQ value with high output of 139.3 µF/cm². Finally, embedding of these TMs (Co, Cu, Ni and Zn) in 2D SiC will provide better alternative to the use of toxic TMs embedded systems such Ti, Mo, Ba and so on.