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Showing papers by "Michael Grätzel published in 1981"


Journal ArticleDOI
01 Jan 1981-Nature
TL;DR: In this article, a bifunctional redox catalyst composed of RuO2 and Pt co-supported on colloidal TiO2 particles is used for water decomposition by visible light illumination.
Abstract: A bifunctional redox catalyst, composed of Pt and RuO2 co-deposited on a colloidal TiO2 carrier, is a highly potent mediator for water decomposition by visible light1. The system contains apart from the sensitizer (Ru(bipy)2+3) an electron relay—methylviologen. The latter is reduced on light excitation, and the photoreaction is coupled with catalytic steps2 generating H2 and O2 from water. To rationalize the surprisingly high efficiency of this photoredox system, we proposed a mechanism involving species adsorbed at the TiO2 surface. This led us to explore sensitizers which through suitable functionalization show an enhanced affinity for adsorption at the particle–water interface. We describe here the performance of electron relay-free systems capable of efficiently decomposing water into H2 and O2 under visible light illumination. A bifunctional redox catalyst composed of RuO2 and Pt co-supported on colloidal TiO2 particles is used. The only other component present is a sensitizer. Amphiphilic surfactant derivatives of Ru(bipy)2+3 exhibit extremely high activity in promoting the water cleavage process. Adsorption of the sensitizer at the TiO2 particle–water interface and electron ejection into the TiO2 conduction band are evoked to explain the observations. Exposure to UV radiation leads to efficient water cleavage in the absence of sensitizer.

353 citations



Journal ArticleDOI
TL;DR: In this paper, the authors present a Web of Science Record created on 2006-02-21, modified on 2017-05-12.Reference LPI-ARTICLE-1981-010
Abstract: Reference LPI-ARTICLE-1981-010View record in Web of Science Record created on 2006-02-21, modified on 2017-05-12

120 citations


Journal ArticleDOI
TL;DR: This poster presents a poster presenting a probabilistic procedure to characterize the response of the immune system to laser-spot assisted, 3D image analysis of central nervous system injury.
Abstract: Reference LPI-ARTICLE-1981-002doi:10.1002/hlca.19810640626View record in Web of Science Record created on 2006-02-21, modified on 2017-05-12

36 citations



Journal ArticleDOI
TL;DR: In this article, the authors present a Web of Science Record created on 2006-02-21, modified on 2017-05-12, with the purpose of improving the quality of the Web.

26 citations


Journal ArticleDOI
TL;DR: In this article, a surfact derivative of phenothiazine was synthesized which is capable of micelle formation in aqueous solution and strong changes in the photochemical behaviour occur.
Abstract: A surfact derivative of phenothiazine was synthesized which is capable of micelle formation in aqueous solution. Concomitantly with micellization, strong changes in the photochemical behaviour occur. In particular, monophotonic photoionization is only observed above the critical micelle concentration (CMC.). Cooperative effects associated with self-assembly of this amphiphilic redox chromophore leading to local electrostatic barriers are evoked to explain these effects.

18 citations


Journal ArticleDOI
TL;DR: In this paper, it was shown that very low energy losses occur when a suitable redox catalyst mediates the oxidation step, showing that the chlorine generation from NaCl evolution takes place.

15 citations


Journal ArticleDOI
TL;DR: The use of dioctadecyldimethylammonium chloride, a cationic surfactant vesicle, to facilitate charge separation and electron storage was investigated in this article.
Abstract: The use of dioctadecyldimethylammonium chloride, a cationic surfactant vesicle, to facilitate charge separation and electron storage was investigated using Ru(bipy)32+(bipy = 2,2′-bipyridyl) and zinc tetra-methylpyridyl porphyrin as sensitizers and an alkyl-substituted methylviologan as an electron relay

8 citations



Journal ArticleDOI
TL;DR: In this paper, the authors propose a method to solve the problem of low energy consumption in the human brain using LPI-ARTICLE-1981-021, which can be found in the Web of Science Notice.
Abstract: Reference LPI-ARTICLE-1981-021Afficher la publication dans Web of Science Notice creee le 2006-02-21, modifiee le 2016-08-08