Structure-tunable Mn₃O₄-Fe₃O₄@C hybrids for high-performance supercapacitor

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Controlling nanomaterial morphology is crucial for optimizing electrochemical properties.
• Metal oxide-carbon composites offer potential for enhanced energy storage applications.

Purpose of the Study:

• To synthesize Mn3O4-Fe3O4@C hybrids with tunable architectures.
• To investigate the structure-property relationships for supercapacitor performance.

Main Methods:

• Incubation of electrospun FeOx-containing carbon fiber (Fe-CNF) in KMnO4 solution.
• Annealing treatment to form Mn3O4-Fe3O4@C hybrids.
• Tuning Fe content in the precursor to control hybrid morphology.

Main Results:

• Successfully synthesized Mn3O4-Fe3O4@C hybrids with half-tube, tube, and oolite-filled fiber structures.
• Oolite-filled Mn3O4-Fe3O4@C exhibited a high specific capacitance of 178 F g-1 at 1 A g-1.
• Achieved excellent cyclic stability with 95% capacitance retention after 1000 cycles at 3 A g-1.

Conclusions:

• The FeOx content in Fe-CNF precursors dictates the final hybrid nanostructure.
• The developed hybrids demonstrate superior electrochemical properties for supercapacitor applications.
• This strategy offers a simple route to engineer nanostructures for high-performance energy storage.