Visible Light-Driven Electron Transfer from a Dye-Sensitized p-Type NiO Photocathode to a Molecular Catalyst in Solution: Toward NiO-Based Photoelectrochemical Devices for Solar Hydrogen Production.
The photoelectrochem. activity of a mesoporous NiO electrode sensitized by a Ru complex was studied with several Rh and Co H2-evolving catalysts. Photocurrent ≤80 $μ$A cm-2 was produced by irradn. of such photocathode in the presence of the Rh(III) polypyridyl complexes, while Co complexes gave almost no photocurrent. Photolysis expts. led to the 2-electron reduced form of the Rh(III) complexes into Rh(I) complexes and demonstrate the occurrence of an electron transfer chain from NiO to the catalyst. Mott-Schottky expts. evidenced the pH dependence of the NiO flat band potential, explaining the dramatic drop of the photocurrent in acidic conditions (cyanoanilinium). By contrast, in weaker acid conditions (formic acid) the photocurrent increases and the key Rh(III) hydride intermediate was efficiently generated. In MeCN soln., Rh(III)-H slowly reacts with HCOOH to generate H2. However, this process was not catalytic, because the redn. potential of the Ru sensitizer is not sufficiently neg. to reduce the Rh(III)-H into Rh(II)-H. [on SciFinder(R)]
Références
- Titre
- Visible Light-Driven Electron Transfer from a Dye-Sensitized p-Type NiO Photocathode to a Molecular Catalyst in Solution: Toward NiO-Based Photoelectrochemical Devices for Solar Hydrogen Production.
- Type de publication
- Article de revue
- Année de publication
- 2015
- Auteurs
- Castillo, Carmen E., Gennari Marcello, Stoll T, Fortage Jérôme, Deronizer Alain, Collomb Marie-Noelle, Sandroni M, Legalite F, Blart E, Pellegrin Y, Delacote C, Boujtita M, Odobel Fabrice, Rannou P, and Sadki S
- Revue
- J. Phys. Chem. C
- Volume
- 119
- Pagination
- 5806–5818
- ISSN
- 1932-7447
Soumis le 12 avril 2018