Bimetallic Pt or Pd-based carbon supported nanoparticles are more stable than their monometallic counterparts for application in membraneless alkaline fuel cell anodes

Alkaline fuel cells (AFCs) are relevant for niche applications, but still require enhanced performance and lifetime. Active durable hydrogen oxidation reaction (HOR) catalysts must be developed: linking their electrochemical surface area (ECSA) loss to HOR activity understanding whether the ECSA of carbon-supported platinum group metal-based (PGM/C) is irreversible (nanoparticles dissolution, detachment, Ostwald ripening) or reversible pivotal. Using identical-location transmission electron micrographs (IL-TEM) characterizations by “CO-like” stripping undertaken pre post accelerated stress tests (AST), different degradation mechanisms undergone monometallic (Pt/C Pd/C) bimetallic (Pd-Pt/C Pd-Ni/C) unveiled. Monometallic PGM/C undergo extensive poisoning upon operation at low potential, in contrast catalysts, which less affected. Pd-Ni exhibits smallest ECSAPGM activity: it poorly catalyzes carbon corrosion hardly poisoned species.