Interfacial Engineering of TiCT MXene Electrode Using g-CN Nanosheets for High-Performance Supercapacitor in Neutral Electrolyte.

The superior performance of the TiCT (MXene)-based supercapacitor in acidic electrolytes has recently gained much interest in the energy storage community. Nevertheless, its performance in most neutral electrolytes is unfavorably low, plausibly due to limited ion diffusion between the MXene layers. Herein, protonated g-CN (pg-CN) is incorporated into the TiCT electrode by using a facile self-assembling process and annealing, which results in increased interlayer -spacing and electrical conductivity of the composite electrode. As a result, the annealed TiCT/pg-CN film revealed an enhanced ion-accessibility and gravimetric capacitance of 140 F g in 1 M aqueous MgSO electrolyte. The cyclic stability test also indicates excellent capacitance retention, with negligible loss of capacitance over 10000 cycles.