High-performance flexible solid-state supercapacitors based on binder-free V2CTx/Ni3S2 nanocomposites on carbon cloth

[Display omitted] •·VNS@CC solves V2CTx self-accumulation problem while increasing the layer spacing.•·As a charge storage site, Ni3S2 significantly increases the surface charge density.•·The sulfur vacancies facilitate the increased involvement of more charge carriers. Designing excellent binder-free composite materials with high performance flexible is an important research direction for energy storage devices. The high theoretical capacity of two-dimensional V2CTx MXene is ideal for electrode materials. However, the interlayer spacing and self-aggregation affect the practical application of the V2CTx. The reduced available surface area and hindered diffusion of electrolytes limit the application development. Designing and constructing self-supporting layered structural composite materials to increase ion transport paths and show excellent structural stability. Herein, the Ni3S2 nanoblock arrays were orderly arranged on the V2CTx supported by carbon cloth. The V2CTx nanosheets are coated on carbon cloth without binder. Thus, the synthesized hierarchical structure significantly increased the surface area with electrolyte penetration and ion transport. Additionally, the interlayer Ni3S2 nanoblock arrays prevent the collapse of the V2CTx interlayers. The designed flexible solid-state hybrid supercapacitor delivers an energy density of 55.69 Wh·kg−1 at a power density of 413.82 W·kg−1 and maintains 91.08 % cycling stability over 10,000 cycles. The strategy results indicate that the constructed composites provide a pathway for binder-free high performance energy storage devices.