On February 3rd, the Journal of the American Chemical Society published the latest research result entitled "Pseudo-Pt Monolayer for Robust Hydrogen Oxidation" by Professor Wang Deli's team in the School of Chemistry and Chemical Engineering.
In the context of carbon peaking and carbon neutrality goals, the "transformative" alkaline membrane fuel cell technology offers the possibility of alleviating one of the bottleneck problems of hydrogen energy conversion -- "Pt atom economy". However, the activity and stability of the catalyst at the anode end of this technology are still worrying, especially since the mechanism of stability decline is not clear, which greatly limits the commercial development of this technology.
To solve the above-quoted problems, Professor Wang Deli's team first proposed a two-stage recession mechanism from the perspective of commercial Pt/C stability: 1. When the potential was lower than 0.5V vs RHE, Pt atoms catalyzed the oxidation of carbon support to produce CO, and CO* species then flowed back to the surface of Pt, resulting in the toxicity of the catalyst and the decrease of the electrochemically active area. 2. When the potential is higher than 0.5V vs RHE, the OH* species in the solution promotes the separation of Pt atoms on the surface of Pt nanocrystals, and the active sites are sharply reduced. The results provide a theoretical basis and design ideas for the development of catalysts with high activity and high stability in alkaline membrane fuel cells.
