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Tungsten Carbide Hollow Microspheres with Robust and Stable Electrocatalytic Activity toward Hydrogen Evolution Reaction.

ABSTRACT: Here, we report a stable tungsten carbide hollow microsphere (W2C-HS) electrocatalyst with robust electrocatalytic activity toward hydrogen evolution reaction fabricated from carburization of tungsten oxides at 700 °C with CH4/H2 flow, which demands overpotentials of 153 and 264 mV to deliver 10 and 100 mA cm-2 ascribing to the hollow structures beneficial for interfacial charge transfer as well as releasing of hydrogen molecular. Meanwhile, the W2C-HS electrocatalyst exhibits undetectable degradation after 20?000 potential cycles indicative of extraordinary durability; in contrast, overpotential@100 mA cm-2 is dramatically increased from 128 to 251 mV after only 2000 potential cycles for benchmark platinum electrocatalyst.

SUBMITTER: Ling Y

PROVIDER: S-EPMC6648149 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Tungsten Carbide Hollow Microspheres with Robust and Stable Electrocatalytic Activity toward Hydrogen Evolution Reaction.

Ling Ying Y Luo Fang F Zhang Quan Q Qu Konggang K Guo Long L Hu Hao H Yang Zehui Z Cai Weiwei W Cheng Hansong H

ACS omega 20190226 2

Here, we report a stable tungsten carbide hollow microsphere (W2C-HS) electrocatalyst with robust electrocatalytic activity toward hydrogen evolution reaction fabricated from carburization of tungsten oxides at 700 °C with CH4/H2 flow, which demands overpotentials of 153 and 264 mV to deliver 10 and 100 mA cm-2 ascribing to the hollow structures beneficial for interfacial charge transfer as well as releasing of hydrogen molecular. Meanwhile, the W ...[more]

PMID: 31459628

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