Facile synthesis of hollow Co3O4-embedded carbon/reduced graphene oxides nanocomposites for use as efficient electrocatalysts in oxygen evolution reaction. (20th March 2019)

• Record Type: Journal Article
• Authors: Zhang, Jiahui; Li, Fang; Chen, Weibin; Wang, Changshui; Cai, Dandan
• Is Part Of: Electrochimica acta. Volume 300(2019)
• Page Start: 123
• Page End: 130
• Publication Date: 2019-03-20
• Subjects: ZIF-67 -- Hollow Co3O4 -- Reduced graphene oxides -- Electrocatalysts -- Oxygen evolution reaction; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2019.01.100
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: The development of non-noble-metal electrocatalysts that are both efficient and stable is of upmost important for the oxygen evolution reaction (OER) in renewable-energy technologies. In this study, cobalt-based zeolitic imidazolate frameworks wrapped by graphene oxide-water (denoted as ZIF-67/GO-W) were successfully prepared by a simple precipitate reaction using water as solvent. Due to the high dispersion of GO in aqueous solution, the synthesis of ZIF-67/GO-W enabled a smaller particle size of ZIF-67 to be attained, also resulted in a more homogeneous distribution between ZIF-67 and GO. Furthermore, a novel hybrid nanostructure comprised of hollow Co3 O4 -embedded carbon/reduced graphene oxides (Co3 O4 C/rGO-W) is achieved through a facile synthetic route involving the calcination-oxidation of ZIF-67/GO-W. The resulting nanocomposites were found to combine the high conductivity of graphene, the promising catalytic properties of the hollow Co3 O4 nanoparticles and a homogeneous distribution of the ZIF-67/GO-W precursor. Enhanced OER activity and improved stability was therefore realized. The hollow Co3 O4 C/rGO-W was found to exhibit a low overpotential (382 mV) and a low tafel slope (62 mV dec −1 ) in 0.1 M KOH, rendering them comparable to the commercial RuO2 catalyst and an improvement to Co3 O4 nanoparticles. This work presents an alternative strategy for the development of uniformly distributed ZIF-67/GO-W using water as solvent and suggests hollow Co3 O4 C/rGO-W as potential electrocatalysts for the OER in energy-related applications. Graphical abstract: Image 105577 Highlights: ZIF-67/GO-W was synthesized by a facile precipitation reaction using water as solvent. Small particle size and homogeneous distribution were realized in the ZIF-67/GO-W. A novel hybrid nanostructure comprised of hollow Co3 O4 C/rGO-W is reported. The hollow Co3 O4 C/rGO-W was used as electrocatalyst for oxygen evolution. The hollow Co3 O4 C/rGO-W exhibits efficient electrocatalytic performance.