Tin-nitrogen/carbon for superior oxygen reduction reaction at fuel cell cathode. (19th April 2023)

• Record Type: Journal Article
• Authors: Sapkota, Prabal; Lim, Sean; Aguey-Zinsou, Kondo-Francois
• Is Part Of: International journal of hydrogen energy. Volume 48:Number 33(2023)
• Page Start: 12433
• Page End: 12443
• Publication Date: 2023-04-19
• Subjects: Tin -- Nitrogen -- Catalyst -- ORR -- PEMFC; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.11.245
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: This work reports on the synthesis of tin-nitrogen/carbon (Sn–N/C) catalysts suitable for the electroreduction of molecular oxygen at the cathode of proton exchange membrane fuel cells. The catalysts were synthesized through a simple pyrolysis process of folic acid as the carbon and nitrogen source, tin chloride as a tin source and Vulcan carbon as the substrate. The synthesized catalyst exhibited excellent oxygen reduction activity with a half wave potential of 0.82 V and a mass activity of 15.5 mA mg −1 . Successful application at the cathode of a self-breathing fuel cell further confirmed the superior performance of this catalyst leading to a power density of 29.4 mW cm −2 . This is very comparable to the reference platinum/Vulcan carbon catalyst (28.4 mW cm −2 ). In addition, this Sn–N/C catalyst showed good stability under accelerated stress tests with only a 12% decrease in fuel cell performance after 10, 000 cycles. The superior performance was assumed to be due to the presence of both metal-nitrogen and nitrogen-carbon active sites, which facilitate the four-electron path of the oxygen reduction reaction. Graphical abstract: A tin-nitrogen/carbon catalyst shows similar performances in polymer electrolyte membrane fuel cells as platinum on Vulcan carbon. Image 1 Highlights: Tin-nitrogen/carbon electrocatalysts could be synthesized through a simple solid-state route. These oxygen reduction catalysts exhibited excellent mass activity compared to the state-of-the-art platinum-based catalysts. When operated in a self-breathing fuel cell, the tin-nitrogen/carbon catalyst achieved the same power density than platinum.