The integrated study of the morphology and the electrochemical behavior of Pt-based ORR electrocatalysts during the stress testing

This article provides relevant information on the catalysts' morphological characteristics that allow for the optimal combination of activity and durability of the materials for proton-exchange membrane fuel cells. The home-made Pt/C and PtCu/C catalysts have been established to have at least by 20% higher values of the mass activity in the oxygen reduction reaction than the commercial Pt/C analogue (HiSPEC 3000, Johnson Matthey). The detailed analysis of the microstructure by transmission electron microscopy and the electrochemical parameters by electrochemical surface-sensitive methods after the stress testing has allowed estimating the contribution of various mechanisms to the degradation process. After the stress testing, the residual activity in the oxygen reduction reaction of the home-made materials has proved to be at least more than double that of the commercial Pt/C catalyst. A specific feature of this work is the presented correlation between the morphology and the electrochemical behavior of the catalysts, with this interconnec- tion appearing to be a valuable resource for a wide range of scientists.& COPY; 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.