CoO nanoparticles deposited on 3D macroporous ozonized RGO networks for high rate capability and ultralong cyclability of pseudocapacitors. Issue 1 (January 2018)

• Record Type: Journal Article
• Authors: Bhattacharya, Pallab; Joo, Taigyu; Kota, Manikantan; Park, Ho Seok
• Is Part Of: Ceramics international. Volume 44:Issue 1(2018)
• Page Start: 980
• Page End: 987
• Publication Date: 2018-01
• Subjects: 3D structure -- High energy -- Graphene -- Cobalt oxide -- Nanocomposite -- Supercapacitor; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2017.10.032
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: The integration of pseudocapacitive metal oxides with reduced graphene oxide (RGO) is considered an innovative chemical strategy to resolve both bottlenecks of pseudocapacitor and electrical double-layer capacitor for high performance supercapacitors. Herein, we report a facile synthesis method of highly porous three-dimensional (3D) CoO/RGO nanocomposite via ozone treatment, ice templating, and thermal annealing. The ozonized RGO surface provides a favorable interaction with cobalt precursor for a stable and uniform deposition of well-defined CoO nanoparticles. The morphology, structure, and chemistry of the resulting CoO/RGO nanocomposites are comprehensively characterized by spectroscopic methods. The CoO/RGO nanocomposites show fast and reversible pseudocapacitance due to a large accessible area, rapid ion transport, and low charge transfer resistance arising from 3D internetworked macroporosity. Thus, the nanocomposites achieve high specific capacitance up to 239.4 F g -1 (volumetric capacitance = 12.04 F cm -3 ), excellent rate capability of 79.1%, and ultralong cyclic stabilities (of 93.2% at 10 A g -1 even up to 10, 000 cycles) in 6 M KOH electrolyte. This simple synthesis method offers a promising solution for the design of high performance hybrid energy storage materials consisting of high capacity metal oxides and conductive graphene networks. Graphical abstract: