Zirconia-decorated V2CT 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. V 2 CT x 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 ZrO 2 -MXene composite where ZrO 2 nano-particles are grown on V 2 CT X MXene sheets. The interconnected structure boosts up the conductivity and suppresses the restacking. The ZrO 2 -V 2 CT x composite showed an outstanding capacitance of ≈ 1200F/g @ 5mVs −1 in 3 M H 2 SO 4 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. • First report on the Zirconia intercalated V 2 CT x MXene sheets as electrode material. • Re-stacking of MXene sheets was worked out by layer modification via ion intercalation. • Resulting electrode showed a remarkable pseudocapacitive behavior and enhanced storage performance. • Modified electrode represents attractive power density and energy density with improved rate capability in 3 M H 2 SO 4