Enhanced oxygen evolution performance of spinel Fe0.1Ni0.9Co2O4/Activated carbon composites. (5th December 2019)

• Record Type: Journal Article
• Authors: Lu, Yi-Ting; Wu, Jianyuan; Lin, Zhi-Xiu; You, Ting-Hsuan; Lin, Sheng-Chi; Tiffany Chen, Hsin-Yi; Hardwick, Laurence J.; Hu, Chi-Chang
• Is Part Of: Electrochimica acta. Volume 326(2019)
• Publication Date: 2019-12-05
• Subjects: Iron-doped nickel cobalt oxide -- Activated carbon -- Oxygen evolution reaction -- Rechargeable zinc-air battery -- Cycling stability; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2019.134986
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: A series of iron-doped nickel cobalt oxide/activated carbon (Fe0.1 Ni0.9 Co2 O4 /AC) composites with various ratios of activated carbon were synthesised via a microwave-assisted hydrothermal method. The introduction of activated carbon significantly promotes the catalytic activity of Fe0.1 Ni0.9 Co2 O4 for the oxygen evolution reaction (OER); meanwhile the complete coverage of nanoparticulate Fe0.1 Ni0.9 Co2 O4 onto activated carbon particles prevents the carbon oxidation, leading to improved cycling durability of a zinc-air cell. Scanning electron microscopy images shows a good protective coverage of the nanoparticulate Fe0.1 Ni0.9 Co2 O4 onto the activated carbon particles. Rotating disk electrode voltammetry and electrochemical impedance spectroscopic results reveal that the OER overpotential and charge-transfer resistance of the Fe0.1 Ni0.9 Co2 O4 electrocatalyst are substantially lowered by the introduction of activated carbon. With respect to the cycling stability, Fe0.1 Ni0.9 Co2 O4 /1.0 wt%AC and Fe0.1 Ni0.9 Co2 O4 /1.5 wt%AC composites maintain excellent activity for 80 h in a rechargeable zinc-air battery, due to the uniformly protective coverage of metal oxide on activated carbon. Furthermore, the Fe0.1 Ni0.9 Co2 O4 /3.7 wt%AC composite was examined in a prolonged rechargeable zinc-air battery test for 120 h and the charge-discharge voltage gap was negligibly enlarged (0.02 V increment after 120 h), which showed their potential as electrocatalysts for long-term energy storage systems. Graphical abstract: The OER activity of Fe0.1 Ni0.9 Co2 O4 is enhanced by the introduction of activated carbon (AC).Image 1 Highlights: Activated carbon (AC) enhances the O2 evolution reaction activity of Fe0.1 Ni0.9 Co2 O4 . Fe0.1 Ni0.9 Co2 O4 particles cover the AC and prevent carbon corrosion. The composite shows stable cycling in the 120-h test. The zinc-air cell shows a power density of 99 mW cm −2 at 100 mA cm −2 .