Effectiveness of Nitrogen-Doping in MXene-Based Composites for Supercapacitor Electrodes

Abstract

The MXenes present a candidate for use as electrode material in the development of supercapacitors due to the presence of numerous interlayer ions, lightweight characteristics, and fast charge/discharge ability. Although MXenes have gained significant attention as an electrode material for supercapacitors, the inherent challenge posed by the stacking of layers due to interlayer van der Waals forces remains unresolved. The incorporation of nitrogen (N) into MXene materials and their composites represents a significant approach to improving their electrochemical properties. N-doped exhibits considerable potential for enhanced electrochemical performance, primarily by facilitating effective interaction between electrolyte ions and carbon-based materials. The N-doping has emerged as an effective modification technique to improve the electrochemical characteristics of MXenes. This review presents a comparative study of the performance enhancement of MXene-based supercapacitor electrodes and their composites through the N-doping technique. Results indicated by N-doping the specific capacitance (SC) of the MXene-based supercapacitors was increased. The SC improvement can be attributed to the synergistic interaction of optimum N levels, augmented interlayer spacing, and improved surface redox activity, facilitating rapid ion intercalation and electron transfer. Levels of doping have been reviewed by various techniques such as photochemical N-doping, ammonium decomposition, thermal treatment, and N sources.

Keywords

• MXene
• Nitrogen-doping
• Composite materials
• Supercapacitor
• Specific capacitance