A Comparison of Pd/C, Perovskite, and Ni-Fe Hexacyanoferrate Bifunctional Oxygen Catalysts, at Different Loadings and Catalyst Layer Thicknesses on an Oxygen Gas Diffusion Electrode. Issue 7 (1st January 2018)

• Record Type: Journal Article
• Authors: McKerracher, R. D.; Figueredo-Rodríguez, H. A.; Avila-Alejo, J. O.; Kwasnicki, K.; de Leόn, C. Ponce; Alegre, C.; Baglio, V.; Aricò, A. S.; Walsh, F. C.
• Is Part Of: Journal of the Electrochemical Society. Volume 165:Issue 7(2018)
• Page Start: A1254
• Page End: A1262
• Publication Date: 2018-01-01
• Subjects: bifunctional oxygen electrode -- hexacyanoferrate -- metal-air battery; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0321807jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Air electrode development is one of the most challenging steps in the design of lightweight and efficient metal-air batteries and fuel cells. The best performing oxygen catalysts often contain precious metals at a high manufacturing cost. In this paper, two low-cost catalysts for the oxygen reduction (ORR) and evolution reactions (OER), based on LSFCO perovskite and Ni-Fe hexacyanoferrate, were compared with a precious metal palladium catalyst on carbon (Pd/C). LSFCO/C showed the best all-round performance as a single bifunctional catalyst but Pd/C had the strongest ORR activity. Ni-Fe hexacyanoferrate is straightforward to manufacture in industrial quantities, and is more active for the OER than palladium and LSFCO perovskite at small loadings < 5 mg cm −2 . By mixing a small loading of Pd/C with Ni-Fe hexacyanoferrate, lower overpotentials for both the ORR and OER can be reached, with the difference in potential between the two reactions being only 0.62 V at a current density of 20 mA cm −2 . The effect of catalyst loading of each catalyst on the gas-diffusion electrode was studied, and rotating disk voltammetry was used to study the catalytic behavior of the Ni-Fe hexacyanoferrate catalyst.