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Imaging nanobubble nucleation and hydrogen spillover during electrocatalytic water splitting.

ABSTRACT: Nucleation and growth of hydrogen nanobubbles are key initial steps in electrochemical water splitting. These processes remain largely unexplored due to a lack of proper tools to probe the nanobubble's interfacial structure with sufficient spatial and temporal resolution. We report the use of superresolution microscopy to image transient formation and growth of single hydrogen nanobubbles at the electrode/solution interface during electrocatalytic water splitting. We found hydrogen nanobubbles can be generated even at very early stages in water electrolysis, i.e., ?500 mV before reaching its thermodynamic reduction potential. The ability to image single nanobubbles on an electrode enabled us to observe in real time the process of hydrogen spillover from ultrathin gold nanocatalysts supported on indium-tin oxide.

SUBMITTER: Hao R

PROVIDER: S-EPMC6003330 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Imaging nanobubble nucleation and hydrogen spillover during electrocatalytic water splitting.

Hao Rui R Fan Yunshan Y Howard Marco D MD Vaughan Joshua C JC Zhang Bo B

Proceedings of the National Academy of Sciences of the United States of America 20180521 23

Nucleation and growth of hydrogen nanobubbles are key initial steps in electrochemical water splitting. These processes remain largely unexplored due to a lack of proper tools to probe the nanobubble's interfacial structure with sufficient spatial and temporal resolution. We report the use of superresolution microscopy to image transient formation and growth of single hydrogen nanobubbles at the electrode/solution interface during electrocatalytic water splitting. We found hydrogen nanobubbles c ...[more]

PMID: 29784824

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