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Origin of high oxygen reduction reaction activity of Pt₁₂ and strategy to obtain better catalyst using sub-nanosized Pt-alloy clusters.

ABSTRACT: In the present study, methods to enhance the oxygen reduction reaction (ORR) activity of sub-nanosized Pt clusters were investigated in a theoretical manner. Using ab initio molecular dynamics and Monte Carlo simulations based on density functional theory, we have succeeded in determining the origin of the superior ORR activity of Pt₁₂ compared to that of Pt₁₃. That is, it was clarified that the electronic structure of Pt₁₂ fluctuates to a greater extent compared to that of Pt₁₃, which leads to stronger resistance against catalyst poisoning by O/OH. Based on this conclusion, a set of sub-nanosized Pt-alloy clusters was also explored to find catalysts with better ORR activities and lower financial costs. It was suggested that Ga₄Pt₈, Ge₄Pt₈, and Sn₄Pt₈ would be good candidates for ORR catalysts.

SUBMITTER: Miyazaki K

PROVIDER: S-EPMC5368974 | biostudies-literature |

REPOSITORIES: biostudies-literature

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