Polyoxothiometalate-Derivatized Silicon Photocathodes for Sunlight-Driven Hydrogen Evolution Reaction.

Autor: Fu D; Université Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR6226, F-35000 Rennes, France., Fabre B; Université Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR6226, F-35000 Rennes, France., Loget G; Université Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR6226, F-35000 Rennes, France., Mériadec C; Université Rennes, CNRS, IPR (Institut de Physique de Rennes)-UMR6251, F-35000 Rennes, France., Ababou-Girard S; Université Rennes, CNRS, IPR (Institut de Physique de Rennes)-UMR6251, F-35000 Rennes, France., Cadot E; Institut Lavoisier de Versailles (UMR-CNRS 8180), UVSQ, Université Paris-Saclay, 45 Avenue de Etats-Unis, 78000 Versailles, France., Leclerc-Laronze N; Institut Lavoisier de Versailles (UMR-CNRS 8180), UVSQ, Université Paris-Saclay, 45 Avenue de Etats-Unis, 78000 Versailles, France., Marrot J; Institut Lavoisier de Versailles (UMR-CNRS 8180), UVSQ, Université Paris-Saclay, 45 Avenue de Etats-Unis, 78000 Versailles, France., de Ponfilly Q; Institut Lavoisier de Versailles (UMR-CNRS 8180), UVSQ, Université Paris-Saclay, 45 Avenue de Etats-Unis, 78000 Versailles, France.
Jazyk: angličtina
Zdroj: ACS omega [ACS Omega] 2018 Oct 22; Vol. 3 (10), pp. 13837-13849. Date of Electronic Publication: 2018 Oct 22 (Print Publication: 2018).
DOI: 10.1021/acsomega.8b01734
Abstrakt: Silicon photocathodes coated with drop-casted {Mo 3 S 4 }-based polyoxothiometalate assemblies are demonstrated to be effective for sunlight-driven hydrogen evolution reaction (HER) in acid conditions. These photocathodes are catalytically more efficient than that coated with the parent thiomolybdate incorporating an organic ligand, as supported by a higher onset potential and a lower overvoltage at 10 mA cm -2 . At pH 7.3, the trend is inversed and the beneficial effect of the polyoxometalate for the HER is not observed. Moreover, the polyoxothiometalate-modified photocathode is found to be also more stable under acid conditions and can be operated at the light-limited catalytic current for more than 40 h. Furthermore, X-ray photoelectron spectroscopy and atomic force microscopy measurements indicate that the cathodic polarization of both photocathodes leads to the release of a large amount of the deposited material into the electrolyte solution concomitantly with the formation of mixed valence species {Mo(IV) 3- x Mo(III) x O 4- n S n } (4- x )+ resulting from the replacement of S 2- sulfido ligands in the cluster by oxo O 2- groups; these combined effects are shown to be beneficial for the photoelectrocatalysis.
Competing Interests: The authors declare no competing financial interest.
Databáze: MEDLINE
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