Ti3C2Tx MXene and Vanadium nitride/Porous carbon as electrodes for asymmetric supercapacitors

MXenes are the emerging class of 2D materials, widely explored as supercapacitor electrodes with their explicit properties. Using the pseudocapacitive nature of the widely reported MXene - TTi3C2Tx, an asymmetric cell is designed with Ti3C2Tx as the negative electrode and Vanadium nitride/Porous carbon as the positive electrode. The asymmetric cell provides a high cell voltage of 1.8 V with a specific capacitance of 105 F/g at 1 A/g in 6 M KOH. It also presents a capacitance retention of 73% even after 10,000 charge-discharge cycles. The asymmetric cell exhibits a high potential window, which is about 3 times higher when compared to symmetric supercapacitors. The asymmetric electrode system exhibits an energy density of 12.81 Wh/kg and a corresponding power density of 985.8 W/kg at 1 A/g. This value of energy density is greater when compared to various symmetric supercapacitors. Thus Ti3C2Tx MXene electrodes can effectively replace the conventional carbon electrodes used in asymmetric supercapacitors. (C) 2020 Elsevier Ltd. All rights reserved.