Zirconia-decorated V2CTx MXene electrodes for supercapacitors

Abstract

The two-dimensional (2D) MXenes are considered efficient electrochemical capacitors (EC) having high energy and power densities with high-rate capabilities as their layered structure provides redox-active surface sites and enhanced electrolytic ion transport simultaneously. V2CTx MXene, one of the lightest members, is theoretically predicted as high performing electrode material for supercapacitors however, restacking of delaminated MXene limits its effective use as EC. We have reported ZrO2-MXene composite where ZrO2 nano-particles are grown on V2CTX MXene sheets. The interconnected structure boosts up the conductivity and suppresses the restacking. The ZrO2-V2CTx composite showed an outstanding capacitance of ≈ 1200F/g @ 5mVs−1 in 3 M H2SO4 which is more than twice the capacitance of pristine MXene. The composite was subjected to cyclic stability up to 10,000 cycles that showed retention of 97 % capacitance. The nonlinear galvanometric charge-discharge (GCD) curves represented the pseudocapacitive nature of composite electrodes with an energy density and power density of 15.39 Wkg−1 and 4000Whkg−1, respectively.