Preparation and Characterization of High-Performance Fe 3 O 4 /RGO Anode for Supercapacitors

As a key factor affecting the performance of supercapacitors, the research on electrode materials for supercapacitors has been primarily focused on the cathode with little work found on anode materials. This has hindered the improvement of the energy density of supercapacitors. The objective of this work, therefore, was to prepare a high-performance, low-cost anode material for supercapacitors. Fe 3 O 4 was synthesized by a hydrothermal method and Fe 3 O 4 /rGO nanocomposites were prepared by further hydrothermal treatment of Fe 3 O 4 with graphene oxide. The Fe 3 O 4 /rGO nanocomposites were characterized by XRD, SEM, TEM, BET. and other methods to analyze their micromorphology and elemental composition. Electrochemical measurements were performed to assess the electrochemical properties of Fe 3 O 4 /rGO, which was tested with a high specific capacitance of 571.2 F g −1 (1 A g −1 ), much higher than that of pure Fe 3 O 4 (214.7 F g −1 ). Assembling Fe 3 O 4 /rGO//MnO 2 asymmetric supercapacitors (ASC) with MnO 2 as the positive electrode and Fe 3 O 4 /rGO as the negative electrode, the device obtained an energy density of 95.1 Wh kg −1 at a power density of 2881 W kg −1 . After 10,000 cycles at 10 A g −1 , the ASC retained 87.2% of its original capacitance, so the Fe 3 O 4 /rGO nanocomposite could be an ideal anode material for high-performance supercapacitors.