Fe2O3@N-C@MnO2 Composite with Chinese-Chestnut Structure for High-Performance Supercapacitors

Utilizing the synergistic effect of binary/ternary transitional metal oxides to boost the electrochemical performance of supercapacitors is demonstrated to be an efficient strategy to construct advanced high-performance supercapacitors. In this work, a ternary Fe 2 O 3 @N-C@MnO 2 (N-C refers to N-doped carbon) composite with a Chinese-chestnut structure was prepared and used as the electrode of a supercapacitor. It was demonstrated that both the high electrical conductivity of N-C and the synergistic effect between Fe 2 O 3 and MnO 2 help to improve the electrochemical performance of the material. At current density of 1 A g −1 , the results show that the specific capacitance of Fe 2 O 3 @N-C@MnO 2 is as high as 1712.5 F g −1 in 1.0 M KOH solution. When the voltage window is 0–1.7 V, the energy density is 17.6 Wh kg −1 and the power density is 424.9 W kg −1 . This work may provide an approach for the design and fabrication of transition metal oxide-based binary/ternary composite electrodes with high electrochemical performance for energy storage devices. Graphical Abstract A ternary composite consisting of Fe 2 O 3 , N-doped carbon, and MnO 2 was synthesized and demonstrated to be an effective electrode of a supercapacitor.