Abstract

A novel class of electrocatalyst for oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cell (PEMFC) was prepared by electrochemically dealloying Pt25Cu75 precursor alloys in a membrane electrode assembly (MEA) cathode. The precursor was prepared by a novel liquid impregnation-freeze drying route. The performance of the electrochemically de-alloyed catalyst was compared to 3 other catalysts, in particular (i) a chemically dealloyed Pt25Cu75, (ii) a precursor Pt-Cu with an atomic ratio of Pt:Cu identical to that of the acid dealloyed catalyst, and (iii) a commercial 30wt% Pt catalyst. The mass activity of the electrochemically dealloyed catalyst @ 0.9V-IR-free is superior to acid dealloyed or as prepared Pt-Cu catalysts and significantly better than reported values of state-of-the-art MEA activities (1). It is observed that electrochemical dealloying of Pt25Cu75 leads to Pt enriched surfaces, results in very Pt-like voltammetric behavior, however, shifts the water activation to more anodic electrode potentials suggesting delayed chemisorption hindering oxygenated species.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.