Jump to main content
Jump to site search

Issue 25, 2017
Previous Article Next Article

Ultrathin Co3O4 nanofilm as an efficient bifunctional catalyst for oxygen evolution and reduction reaction in rechargeable zinc–air batteries

Author affiliations

Abstract

Two-dimensional (2D) nanocatalysts with a large specific surface area and efficient charge conductivity are promising candidates for catalyzing the sluggish oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), which are at the heart of various electrochemical energy conversion and storage technologies. Here, we report the synthesis of an ultrathin Co3O4 nanofilm with a thickness of nearly 1.8 nm via a surfactant- and template-free facile hydrothermal route. The proposed synthesis strategy can be extended to the preparation of 2D NixCo3−xO4 and FexCo3−xO4 nanostructures. The synthesized Co3O4 nanofilm exhibited bifunctional activity that was superior to that of the counterpart Co3O4 nanoparticles, including a lower overpotential and higher reduction and evolution current densities, and demonstrated faster catalytic kinetics over the 2D nanofilm surface. In comparison with precious metal-based catalysts, to achieve an OER current density of 40 mA cm−2 the overpotential of the nanofilm (461 mV) was lower than that of RuO2 (526 mV), whereas the ORR on the nanofilm proceeded via a dominant 4e transfer mechanism, which is similar to that of commercial carbon-supported Pt (Pt/C). The Co3O4 nanofilm enabled the assembly of rechargeable Zn–air batteries with a lower overpotential (0.72 V), higher round-trip efficiency (62.7%), and a longer cycle lifetime (175 cycles). The remarkable bifunctional activity contributes to an increase in the number of electrochemically active sites, a large interfacial contact area with the electrolyte, and the enrichment of Co3+ ions on the surface, which facilitates the adsorption and activation of oxygen-containing species. This study should shed light on the future development of new electroactive materials with optimized 2D nanostructures to enhance the overall bifunctional ORR/OER performance of rechargeable metal–air batteries.

Graphical abstract: Ultrathin Co3O4 nanofilm as an efficient bifunctional catalyst for oxygen evolution and reduction reaction in rechargeable zinc–air batteries

Back to tab navigation

Supplementary files

Publication details

The article was received on 04 Apr 2017, accepted on 05 May 2017 and first published on 12 May 2017


Article type: Paper
DOI: 10.1039/C7NR02385E
Citation: Nanoscale, 2017,9, 8623-8630
  •   Request permissions

    Ultrathin Co3O4 nanofilm as an efficient bifunctional catalyst for oxygen evolution and reduction reaction in rechargeable zinc–air batteries

    Y. He, J. Zhang, G. He, X. Han, X. Zheng, C. Zhong, W. Hu and Y. Deng, Nanoscale, 2017, 9, 8623
    DOI: 10.1039/C7NR02385E

Search articles by author

Spotlight

Advertisements