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Dealloying of Nitrogen-Introduced Pt-Co Alloy Nanoparticles: Preferential Core-Shell Formation with Enhanced Activity for Oxygen Reduction Reaction.

ABSTRACT: Voltammetric dealloying is a typical method to synthesize Pt-shell/less-noble metal (M) alloy core nanoparticles (NPs) toward the oxygen reduction reaction (ORR). The pristine nanostructures of the Pt-M alloy NPs should determine the ORR activity of the dealloyed NPs. In this study, we investigated the voltammetric dealloying behavior of the Pt-Co and nitrogen-introduced Pt-Co alloy NPs generated by synchronous arc-plasma deposition of Pt and Co. The results showed that the dealloying behavior is sensitive to cobalt nitride in the pristine NPs, leading to the preferential generation of a Pt-rich shell/Pt-Co alloy core architecture having enhanced ORR activity.

SUBMITTER: Takahashi S

PROVIDER: S-EPMC6640784 | biostudies-literature |

REPOSITORIES: biostudies-literature

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