Excellent Bifunctional Oxygen Evolution and Reduction Electrocatalysts (5A1/5)Co2O4 and their Tunability

Author

Xin Wang
Harish Singh
Manashi Nath, Missouri University of Science and TechnologyFollow
Kurt Lagemann
Katharine Page

Abstract

Hastening the Progress of Rechargeable Metal-Air Batteries and Hydrogen Fuel Cells Necessitates the Advancement of Economically Feasible, Earth-Abundant, Inexpensive, and Efficient Electrocatalysts Facilitating Both the Oxygen Evolution Reaction (OER) and Oxygen Reduction Reaction (ORR). Herein, a Recently Reported Family of Nano (5A1/5) Co2O4 (A = Combinations of Transition Metals, Mg, Mn, Fe, Ni, Cu, and Zn) Compositionally Complex Oxides (CCOs) [Wang Et Al., Chemistry of Materials, 2023, 35 (17), 7283-7291.] Are Studied as Bifunctional OER and ORR Electrocatalysts. among the Different Low-Temperature Soft-Templating Samples, Those Subjected to 600 °C Post annealing Heat Treatment Exhibit Superior Performance in Alkaline Media. One Specific Composition (Mn0.2Fe0.2Ni0.2Cu0.2Zn0.2) Co2O4 Exhibited an Exceptional overpotential (260 MV at 10 MA Cm-2) for the OER, a Favorable Tafel Slope of 68 MV Dec-1, Excellent Onset Potential (0.9 V) for the ORR, and Lower Than 6% H2O2 Yields over a Potential Range of 0.2 to 0.8 V vs. the Reversible Hydrogen Electrode. Furthermore, This Catalyst Displayed Stability over a 22 H Chronoamperometry Measurement, as Confirmed by X-Ray Photoelectron Spectroscopy Analysis. Considering the Outstanding Performance, the Low Cost and Scalability of the Synthesis Method, and the Demonstrated Tunability through Chemical Substitutions and Processing Variables, CCO ACo2O4 Spinel Oxides Are Highly Promising Candidates for Future Sustainable Electrocatalytic Applications.

Recommended Citation

X. Wang et al., "Excellent Bifunctional Oxygen Evolution and Reduction Electrocatalysts (5A1/5)Co2O4 and their Tunability," ACS Materials Au, vol. 4, no. 3, pp. 274 - 285, American Chemical Society, May 2024.

The definitive version is available at https://doi.org/10.1021/acsmaterialsau.3c00088

Department(s)

Chemistry

Publication Status

Open Access

Comments

University of Tennessee, Grant None

International Standard Serial Number (ISSN)

2694-2461

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2024 American Chemical Society, All rights reserved.

Creative Commons Licensing

This work is licensed under a Creative Commons Attribution 4.0 License.

Publication Date

08 May 2024