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Shape-Controlled Synthesis of Dumbbell-like Pt-Fe₃O₄-MnO _x Nanoparticles by Governing the Reaction Kinetics.

ABSTRACT: The production of shape-controlled heterometallic nanoparticles (NPs) consisting of Pt and nonprecious metal oxides is crucial to demonstrate the composition-property relationship of NPs. Herein, we report a facile one-pot approach for the controlled synthesis of dumbbell-like Pt-Fe₃O₄-MnO _x and dendritic Pt-MnO _x NPs. The key to the success of this synthesis is in changing the quantity of Fe(CO)₅ additive to control the reaction kinetics. In the absence of Fe(CO)₅, dendritic Pt-MnO _x NPs were synthesized through the assembly of small seed NPs. On the other hand, dumbbell-like Pt-Fe₃O₄-MnO _x NPs were obtained in the presence of Fe(CO)₅ through controlling the nucleation and growth of Fe and Mn on the Pt NPs, followed by air oxidation. Compared to a Pt/graphene oxide (GO) catalyst, dumbbell-like Pt-Fe₃O₄-MnO _x NPs on GO showed an enhancement of specific activity toward the oxygen reduction reaction owing to the compressive-strain effect exerted on the Pt lattice.

SUBMITTER: Woo H

PROVIDER: S-EPMC6644934 | biostudies-literature |

REPOSITORIES: biostudies-literature

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