Selenized Binary Transition Metals-MXene Composite for High-Performance Asymmetric Hybrid Capacitors.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• High-performance supercapacitors require innovative energy storage materials.
• MXene (Ti3C2Tx) and NiCo2Se4 offer promising properties for energy storage applications.

Purpose of the Study:

• To synthesize and characterize a novel composite of multilayered MXene and porous NiCo2Se4 nanosheets.
• To evaluate the electrochemical performance of the composite for supercapacitor applications.
• To investigate the synergistic effects between MXene and NiCo2Se4 for enhanced energy storage.

Main Methods:

• Synthesis of a composite material integrating multilayered MXene (Ti3C2Tx) nanoparticles with porous NiCo2Se4 nanosheets.
• Characterization of the nanostructure and interfacial properties of the composite.
• Electrochemical testing of the composite electrode in a supercapacitor configuration.
• Fabrication and testing of an asymmetric hybrid capacitor using the composite material and activated carbon.

Main Results:

• The composite exhibited an accordion-like nanostructure with enhanced surface area and cycling stability.
• The material achieved a high specific capacity of 796.25 C g-1 at 1 A g-1 with over 90% capacity retention after 8000 cycles.
• The asymmetric hybrid capacitor delivered an energy density of 64.36 Wh kg-1 at 0.8 kW kg-1.

Conclusions:

• The synergistic interaction between MXene and NiCo2Se4 significantly improved electrochemical activity and ion transport.
• The developed composite material demonstrates excellent potential for high-performance supercapacitors.
• This novel material structure is suitable for integration into various electrochemical devices, including batteries, sensors, and electrolyzers.