Zirconia-decorated V2CTx MXene electrodes for supercapacitors

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 approximate to 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 rep-resented the pseudocapacitive nature of composite electrodes with an energy density and power density of 15.39 Wkg 1 and 4000Whkg 1, respectively.

Automated summary

Two-dimensional MXenes are efficient electrochemical capacitors with high energy and power densities. V2CTx MXene, as one of the lightest members, is limited in its effective use due to restacking. A composite of ZrO2-MXene was reported, where ZrO2 nanparticles were grown on V2CTx MXene sheets. The interconnected structure boosted conductivity and suppressed restacking. This composite showed outstanding capacitance and cyclic stability.