High-performance asymmetric supercapacitors based on 2D MXene/NiCoP hybrid and ZIF derived porous nanocarbon

Abstract

The performance of supercapacitors can be improved by strategically designing 2D MXene-based electrodes with excellent electrochemical properties. However, several challenges remain in developing hybrid materials based on 2D MXenes due to restacking, which hinders energy storage performance. In this work, we successfully synthesized a 2D MXene/Ni-Co phosphide (MX/NCP) hybrid material for supercapacitors via a facile hydrothermal reaction followed by phosphorization. The optimized MX/NCP positive electrode showed good energy storage performance with a specific capacitance of 1754.0 F g⁻¹ at 3 mA cm⁻² in a three-electrode configuration. The synergistic effect of MXene and Ni-Co phosphide has contributed towards the enhanced charge storage performance. Furthermore, an asymmetric supercapacitor (ASC) fabricated with MX/NCP and porous nanocarbon (PNC) delivered a maximum energy density of 54.3 Wh kg⁻¹ at a power density of 565.6 W kg⁻¹ with a cycling stability of 93.8% after 10000 cycles. To evaluate the practical versatility of the ASC, a planar device was successfully fabricated making MX/NCP a promising electrode material in next-generation wearable and flexible supercapacitors.