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Platinum-nickel alloy excavated nano-multipods with hexagonal close-packed structure and superior activity towards hydrogen evolution reaction.

ABSTRACT: Crystal phase regulations may endow materials with enhanced or new functionalities. However, syntheses of noble metal-based allomorphic nanomaterials are extremely difficult, and only a few successful examples have been found. Herein, we report the discovery of hexagonal close-packed Pt-Ni alloy, despite the fact that Pt-Ni alloys are typically crystallized in face-centred cubic structures. The hexagonal close-packed Pt-Ni alloy nano-multipods are synthesized via a facile one-pot solvothermal route, where the branches of nano-multipods take the shape of excavated hexagonal prisms assembled by six nanosheets of 2.5 nm thickness. The hexagonal close-packed Pt-Ni excavated nano-multipods exhibit superior catalytic property towards the hydrogen evolution reaction in alkaline electrolyte. The overpotential is only 65 mV versus reversible hydrogen electrode at a current density of 10 mA cm^-2, and the mass current density reaches 3.03 mA μgPt^-1 at -70 mV versus reversible hydrogen electrode, which outperforms currently reported catalysts to the best of our knowledge.

SUBMITTER: Cao Z

PROVIDER: S-EPMC5413976 | biostudies-literature |

REPOSITORIES: biostudies-literature

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