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Coupled molybdenum carbide and reduced graphene oxide electrocatalysts for efficient hydrogen evolution.

ABSTRACT: Electrochemical water splitting is one of the most economical and sustainable methods for large-scale hydrogen production. However, the development of low-cost and earth-abundant non-noble-metal catalysts for the hydrogen evolution reaction remains a challenge. Here we report a two-dimensional coupled hybrid of molybdenum carbide and reduced graphene oxide with a ternary polyoxometalate-polypyrrole/reduced graphene oxide nanocomposite as a precursor. The hybrid exhibits outstanding electrocatalytic activity for the hydrogen evolution reaction and excellent stability in acidic media, which is, to the best of our knowledge, the best among these reported non-noble-metal catalysts. Theoretical calculations on the basis of density functional theory reveal that the active sites for hydrogen evolution stem from the pyridinic nitrogens, as well as the carbon atoms, in the graphene. In a proof-of-concept trial, an electrocatalyst for hydrogen evolution is fabricated, which may open new avenues for the design of nanomaterials utilizing POMs/conducting polymer/reduced-graphene oxide nanocomposites.

SUBMITTER: Li JS

PROVIDER: S-EPMC4822009 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Carbon Nanotube Supported Molybdenum Carbide as Robust Electrocatalyst for Efficient Hydrogen Evolution Reaction.

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CoSe2 nanobelt coupled with CoMoO4 nanosheet as efficient electrocatalysts for hydrogen and oxygen evolution reaction

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Nanostructured Nickel Nitride with Reduced Graphene Oxide Composite Bifunctional Electrocatalysts for an Efficient Water-Urea Splitting.

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Facile Synthesis of Molybdenum Diselenide Layers for High-Performance Hydrogen Evolution Electrocatalysts.

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