Graphene and activated carbon-wrapped and Co3O4-intercalated 3D sandwich nanostructure hybrid for high-performance supercapacitance. (31st May 2018)

• Record Type: Journal Article
• Authors: Li, Yue; Jia, Mengying; Xu, Lanshu; Gao, Jianmin; Zhang, Fan; Jin, Xiao-Juan
• Is Part Of: New journal of chemistry. Volume 42:Number 13(2018)
• Page Start: 10733
• Page End: 10740
• Publication Date: 2018-05-31
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c8nj01160e
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : The graphene/Co3 O4 /activated carbon (GCA) 1 : 9 capacitor shows the best electrochemical properties with Co3 O4 particles that were homogeneously dispersed between the graphene/Co3 O4 (GC) layers. Abstract : A graphene/Co3 O4 /activated carbon (GCA) hybrid with excellent electrochemical properties for supercapacitance was successfully fabricated via a simple two-step hydrothermal method. The as-synthesized hybrid was examined by transmission electron microscopy (TEM), X-ray diffraction (XRD), and electrochemical characterization. The results confirmed that Co3 O4 particles were homogeneously distributed between the graphene and activated carbon layers. The GCA 1 : 9 capacitor (GC : AC = 9 : 1) showed the best electrochemical property compared with other hybrid capacitors. The specific capacitance of the GCA 1 : 9 hybrid capacitor is 564 F g −1 with activated carbon (AC) covering the outside of the graphene/Co3 O4 (GC) layers. The specific capacitance of the GCA 1 : 9 was improved by 53.26% compared with the GC composite capacitor (368 F g −1 ) at 50 mA g −1 in 7 M KOH. The GCA 1 : 9 also exhibits outstanding cycling property with 90.43% capacitance retention over 10 000 cycles at a current density of 20 A g −1 . Moreover, it also achieved a high energy density of 35.7 W h kg −1 at a power density of 235.5 W kg −1, demonstrating that it is a promising candidate for supercapacitance.