High-performance supercapacitor electrodes of MXene/PANI/carbon fiber hybrid composites with 2D/0D/1D hierarchical nanostructures

MXene-based electrodes have shown great performance as flexible supercapacitors in the application of portable and wearable electronics. Nevertheless, 2D MXene nanosheets suffer from severe self-stacking issues during electrode preparation, which can significantly limit the charge storage capacity. Herein, a simple yet efficient strategy is developed for fabricating the supercapacitor electrode based on the MXene@PANI coated activated carbon cloth (MXene@PANI-ACC). The resulting MXene@PANI-ACC possesses 2D/0D/1D hierarchical nanostructures , where the 1D carbon fibers are uniformly coated with MXene@PANI nanocomposites and the 0D PANI nanoparticles are densely anchored on the surfaces of the 2D MXene nanosheets. This hierarchical structure can effectively tackle the restacking issue of MXene nanosheets during electrode fabrication and provide the obtained electrode with good conductivity for fast electron transfer . Benefiting from those features, this MXene@PANI-ACC electrode demonstrates an excellent area capacitance of 1347 mF/cm 2 at a current density of 1 mA/cm 2 and can retain of its original capacity at 20 mA/cm 2 after 5000 cycles. The excellent electrochemical performance highlights great promise of the developed electrode with hierarchical nanostructures for applications in high-performance energy storage devices.