Electrophoretically-Deposited Nano-Fe3O4@carbon 3D Structure on Carbon Fiber as High-Performance Supercapacitors

Structural and electrochemical behaviors of electrophortically-deposited Fe 3 O 4 and Fe 3 O 4 @C nanoparticles on carbon fiber (CF) were investigated. The nanoparticles were synthesized via a green-assisted hydrothermal route. The as-prepared samples were characterized by x-ray diffraction, transmission and scanning electron microscopies, Fourier transform infrared and UV–visible spectroscopies as well as by a vibration sample magnetometer. Surprisingly, the saturation magnetization ( M s ) of the Fe 3 O 4 @C (~ 26.99 emu/g) was about 20% higher than that of Fe 3 O 4 nanoparticles. A rather rectangular CV curve for both the elecrophortically-deposited Fe 3 O 4 and Fe 3 O 4 @C on CF indicated the double-layer supercapacitor behavior of the samples. The synergistic effects of double shells improved the electrochemical behavior of Fe 3 O 4 @CF. The Fe 3 O 4 @C@CF composite exhibited a higher specific capacitance of ~ 412 F g −1 at scan rate of 0.05 V/s compared to the Fe 3 O 4 @CF with a value of ~ 193 F g −1 . The superb electrochemical properties of Fe 3 O 4 @C@CF confirm their potential for applications as supercapacitors in the energy storage field.