Fe3O4-based core/shell nanocomposites for high-performance electrochemical supercapacitors

• Published in: Journal of materials science Vol. 51; no. 3; pp. 1572 - 1580
• Main Authors: Wu, Qianhui, Chen, Ming, Chen, Kaiyu, Wang, Shishuang, Wang, Chengjiao, Diao, Guowang
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.02.2016; Springer Nature B.V
• Subjects: Capacitance; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Crystallography and Scattering Methods; Discharge; Electrochemical analysis; Electrochemical impedance spectroscopy; Electrode materials; Electrons; Energy storage; Fourier transforms; Iron oxides; Materials Science; Microprocessors; Nanocomposites; Nanomaterials; Original Paper; Polyanilines; Polymer Sciences; Solid Mechanics; Spectrum analysis; Supercapacitors; Synergistic effect; Transmission electron microscopy; X-ray diffraction; Fe3O4; Specific Capacitance; PANI; High Specific Capacitance; Ultrasonic Irradiation
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-015-9480-4

In this work, magnetite (Fe 3 O 4 )-based core/shell composites, including Fe 3 O 4 @carbon (C), Fe 3 O 4 @polyaniline (PANI), and Fe 3 O 4 @C@PANI, are synthesized via a facile hydrothermal process. The as-prepared core/shell composites are characterized by transmission electron microscopy, X-ray diffraction powder, and Fourier transform infrared spectroscopy. The electrochemical performances of Fe 3 O 4 , Fe 3 O 4 @C, Fe 3 O 4 @PANI, and Fe 3 O 4 @C@PANI are investigated using cyclic voltammetry, galvanostatic charge–discharge measurement, and electrochemical impedance spectroscopy. The results show that the as-prepared nanomaterials are all typical pseudocapacitance capacitors. Carbon shell can significantly increase the electronic conductivity of electrode materials, reduce capacity loss, and improve the reversibility of Fe 3 O 4 . PANI coating layer can expressively enhance the specific capacitance. Synergistic effect of double shells improves the electrochemical property of Fe 3 O 4 . Fe 3 O 4 @C@PANI composites display the high capacitance of 322.5 F g −1 at 2.5 A g −1 , and 87.8 % of which can still be maintained after 3000 charge–discharge cycles. The excellent electrochemical properties of Fe 3 O 4 @C@PANI evidence their potential application as supercapacitors in energy storage field.