NiCoP/MXene nanocomposites via electrostatic self-assembly for high-performance supercapacitor electrodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Bimetallic phosphides offer high specific capacity for energy storage.
• Volume expansion and sluggish kinetics limit phosphide-based supercapacitor stability.

Purpose of the Study:

• To develop stable and high-performance supercapacitor electrodes using NiCoP/MXene composites.
• To investigate the influence of MXene content on the electrochemical properties of NiCoP/MXene.

Main Methods:

• Solvothermal synthesis followed by phosphidization to create NiCoP/MXene.
• Electrochemical characterization of the composite electrodes at various MXene loadings.
• Fabrication and testing of an asymmetric supercapacitor device.

Main Results:

• The optimized NiCoP/MXene electrode (NCP/MX-20/CC) achieved a specific capacity of 848.83 C g^-1 at 1 A g^-1.
• Exceptional cyclic stability was observed, with 86.57% capacity retention after 5000 cycles.
• The composite electrode exhibited battery-type behavior with surface-controlled charge storage mechanisms.

Conclusions:

• NiCoP/MXene composites significantly enhance supercapacitor performance due to increased surface area, conductivity, and faster kinetics.
• The developed asymmetric supercapacitor demonstrates a high energy density of 49.7 W h kg^-1 and durability.
• NiCoP/MXene materials show great promise for advanced supercapacitor applications.