Abstract: Two dimensional Fe₃O₄@C nanosheet was prepared by facile and effective in situ deposition crystallization followed by pyrolysis route using sucrose as carbon source and sodium chloride as template. The structure and electrochemical energy storage properties of Fe₃O₄@C nanosheet were characterized. The results showed that Fe₃O₄@C nanosheet is made of 2D graphitic carbon nanosheets, which uniform Fe₃O₄ nanoparticles were embedded. The thickness of Fe₃O₄@C nanosheet was less than 100 nm with the specific surface area 255 m²/g and average pore size 3.79 nm, and the mass fraction of Fe₃O₄ was 36.98%. Besides, the results of the electrochemical energy storage performance showed that Fe₃O₄@C nanosheet exhibited high specific capacitance and excellent rate capability (436 F/g at 1 A/g, and still up to 332 F/g at 20 A/g). However, the cycle stability of it was poor, over 500 cycles at 10 A/g, the specific capacitance dropped to 178 F/g, only 50.71% of the initial value.

Key words: supercapacitor, Fe₃O₄, carbon nanosheets, electrode materials, cycling stability