Polyaniline-MXene composite electrode with excellent electrochemical properties for all-solid flexible supercapacitors

In this paper, MXene based electrode active materials and MXene cross-linked polyacrylic acid hydrogel electrolytes with high cycling performance and high specific capacitance have been successfully prepared. Poly aniline with high capacitance values has been grown on the MXene surface by in situ polymerization, which can significantly improve electrochemical properties. As the MXene surface is rich in functional groups, it can be used as a nucleation site for in situ polymerization of aniline monomers deposited. The PANI filled with MXene forms a 3D porous conductive network reducing the self-stacking of MXene and providing a large number of channels for electrolyte ions to enter MXene. The supercapacitor has been tested and assembled with good flexibility and the specific capacitance has risen to 222 F g-1. The capacitance retention of 98.5 % after 10,000 charges and discharges is due to the improved performance of the composite material and the excellent stability of the gel electrolyte and electrodes. The above results show that the prepared electrodes and devices have promising applications in flexible wearable devices.