Enhanced radical scavenging performance of Pt@CeO2 via strong metal-support interaction effect for improving durability of proton exchange membrane fuel cell

Since scavenging free radical is regarded as an efficient strategy to enhance the durability of proton exchange membrane fuel cells (PEMFCs), strong metal-support interaction (SMSI) effect between metal and reducible oxide supports is employed as a strategy to moderate the number of accessible active sites for reduction-oxidation reaction. Enriched Pt–CeO2 interface to enhance SMSI effect is achieved as well via constructing multicore-shell structure Pt@CeO2. Theoretical calculation confirms that SMSI effect at Pt–CeO2 interface endows electrons flowing from Pt to CeO2 to reduce the formation energy of oxygen vacancies, while Pt@CeO2 with higher magnitude of lattice distortion plan provides enriched Pt–CeO2 interface that made more concentration of Ce3+ ions feasible. Results show that better free radical scavenging performance is achieved with higher concentration of Ce3+ ions in Pt@CeO2. Based on the open circuit voltage (OCV) test, the Pt@CeO2-modified membrane in this work decays at only 70% of the commercial membrane, while 65% of the maximum power is still maintained after the test. This superior performance to the commercial membrane indicates this designed structure with SMSI effect could be considered as a potential route to solve the free radical problem in PEM for enhanced durability of PEMFCs.