Micro-Structural and Flexible Reduced Graphene Oxide/Ti₃C₂T_x Composite Film Electrode with Long Cycle Life for Supercapacitor

Poor rate capability due to the sheet self-stacking of conventional MXene electrode limits their electrochemical application to some extent. Herein, incorporating reduced graphene oxide into Ti₃C₂T_x MXene is reported to improve the electrochemical performance, cycle lifetime, and mechanical flexibility significantly. Graphene oxide is reduced by thermal heating, by which it can release gas locally to induce micro-surface structure. The resulting film with an introduction of 20 wt% graphene oxide exhibits an expansion of the interlayer space to multiply the active sites and thereby lead to a specific capacitance of up to 322 F g⁻¹ at 1 A g⁻¹ in 3 m H₂SO₄ electrolyte. In addition, the fabricated composite electrode also exhibits an excellent cycle stability and mechanical flexibility even after 32 000 charge/discharge cycles. This work provides a progressive strategy to synthesize micro-structural and flexible MXene-based electrode for the future application in flexible energy storage devices.