Preparation of Co/CoOx Derived from a Low-temperature Etching of ZIF-67 for Oxygen Reduction and Oxygen Evolution Catalytic Reaction

• Published in: Journal of Wuhan University of Technology. Materials science edition Vol. 38; no. 6; pp. 1255 - 1261
• Main Authors: Tan, Shifeng, Tu, Wenmao, Pan, Hongfei, Zhang, Haining
• Format: Journal Article
• Language: English
• Published: Wuhan Wuhan University of Technology 01-12-2023; Springer Nature B.V
• Subjects: Advanced Materials; Catalytic activity; Chemistry and Materials Science; Cobalt oxides; Controllability; Electrocatalysts; Etching; Functional groups; Graphene; Low temperature; Materials Science; Oxidation; Oxygen; Roasting; Synthesis; Vaporization; oxygen evolution reaction; oxygen reduction reaction; ZIF-67; bifunctional electrocatalyst
• ISSN: 1000-2413; 1993-0437
• DOI: 10.1007/s11595-023-2817-y

Catalysts consisting of Zeolite imidazolyl ester skeleton-67 (ZIF-67) and graphene oxide (GO) were fabricated through a solvothermal method, followed by etching ZIF-67 with oxygen-rich functional groups on GO in a reduction atmosphere at 400 °C. During this process, an open type of cobalt metal center was formed by the partial vaporization and oxidation of ZIF-67, further reducing to Co and partially combining with oxygen species to amorphous CoO
x
. Benefiting from the rich functional N, and metal/oxides active centers derived from the calcination process, the synthesized Co/CoO
x
@NSG-400 showed a low OER overpotential of 10 mA·cm
−2
at 298 mV, and an ORR half-wave potential of 0.8 V, which demonstrated its excellent bifunctional catalytic activity. Such a controllable calcination strategy with high yields could be expected to pave the way for synthesizing low-cost and efficient bifunctional electrocatalysts.