Acupressure mat-like hierarchical structure of Ni3S2@Ti3C2Tx nanosheets as high rate capability and high power density electrodes for advanced supercapacitor

Layered material Ti3C2Tx has good pseudo capacitance properties, but its structure is unstable, and it was easily affected by water molecules in the air, which seriously limits its application in practical applications. The electrostatic self-assembly of nanoparticle Ni3S2 solid polyhedron provides more active sites for pseudo capacitive reaction, and the ion transport resistance is low, which provides a buffer space when the structure changes, and overcomes the structural instability of the carbon-based material (Ti3C2Tx) and the low theoretical specific capacity. Ti3C2Tx layered material was used as a stable conductive network substrate for charge transfer interconnection, which further improves the charge transfer rate between multi-layer structures, and successfully prepares Acupressure Mat-like Hierarchical Structure Ni3S2 @Ti3C2Tx composite material. It was capacity retention rate can reach 98% after 5000 cycles at a current density of 2 A/g. The assembled SSC unit has a huge potential window of 0–1.6 V, excellent magnification performance (93%), high power density (792.1 W/kg), and energy density (71.7 Wh/kg). The solid polyhedral Ni3S2 @layeredTi3C2Tx composite material has a good synergistic effect. It can synergistically reduce the expansion and collapse of materials, realize the steady improvement of electrochemical properties such as rate characteristics and energy density, and provide a potential application prospect for SSCs with high energy density.