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A nickel nanocatalyst within a h-BN shell for enhanced hydrogen oxidation reactions.

ABSTRACT: The development of low-cost and high-performance electrocatalysts remains a challenge for the hydrogen oxidation reaction (HOR) in alkaline membrane fuel cells. Here, we have reported novel Ni@h-BN core-shell nanocatalysts consisting of nickel nanoparticles encapsulated in few-layer h-BN shells. The Ni@h-BN catalysts exhibit an improved HOR performance compared with the bare Ni nanoparticles. In situ characterization experiments and density functional theory calculations indicate that the interactions of the O, H, and OH species with the Ni surface under the h-BN shell are weakened, which helps to maintain the active metallic Ni phase both in air and in the electrolyte and strengthen the HOR processes occurring at the h-BN/Ni interfaces. These results suggest a new route for designing high-performance non-noble metal electrocatalysts with encapsulating two-dimensional material overlayers for HOR reactions.

SUBMITTER: Gao L

PROVIDER: S-EPMC5621155 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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A nickel nanocatalyst within a h-BN shell for enhanced hydrogen oxidation reactions.

Gao Lijun L Wang Ying Y Li Haobo H Li Qihao Q Ta Na N Zhuang Lin L Fu Qiang Q Bao Xinhe X

Chemical science 20170609 8

The development of low-cost and high-performance electrocatalysts remains a challenge for the hydrogen oxidation reaction (HOR) in alkaline membrane fuel cells. Here, we have reported novel Ni@h-BN core-shell nanocatalysts consisting of nickel nanoparticles encapsulated in few-layer h-BN shells. The Ni@h-BN catalysts exhibit an improved HOR performance compared with the bare Ni nanoparticles. <i>In situ</i> characterization experiments and density functional theory calculations indicate that the ...[more]

PMID: 28989613

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