3D porous MXene induced by zinc-assisted electrodeposition for flexible all-solid-state supercapacitors

The MXene Ti 3 C 2 T x shows good promise for use in energy storage applications. 2D MXene sheets exhibit serious restacking problems, so these MXene sheets are assembled into 3D macro structures to develop MXene-based functional materials. However, existing methods for the macro assembly of 3D MXenes usually require high temperatures and high-concentration MXene solutions, which exacerbate the oxidation of MXene and result in poor surface utilization. In this paper, a simple and rapid zinc-assisted electrodeposition strategy utilizing a lowconcentration MXene solution was used to successfully prepare Ti 3 C 2 T x MXene hydrogel. This self-assembled 3D porous structure inhibits MXene layer stacking, shortens the electrolyte ion transport/diffusion pathways, and exposes a higher number of electrochemically active sites. As a supercapacitor electrode, Zn-Ti 3 C 2 T x exhibits good capacitance (352 F g -1 at 2 mV s -1 ) and excellent rate performance (73.3% at 1 V s -1 ). The assembled ZnTi 3 C 2 T x /carbon cloth all-solid symmetric supercapacitor (ASSC) device exhibits excellent energy density (11.65 Wh kg -1 ) under a power density of 104.85 W kg -1 . This research offers new ideas for designing porous MXene-based materials.