Photoreduction methylviologen

The first report on photocurrent measurements at liquid-liquid interfaees was published by Marecek et al. for the photoreduction of methylviologen in the aqueous phase by Ru(bpy)3 located in the organic phase (DCE or benzonitrile) [48],... 

AOT-isooctane-H20 reversed micelles 50-A-diameter CdS particles generated in situ in reversed micelles from CdCl2 or Cd(N03)2 by H2S Reversed-micelle-entrapped CdS was fluorescence quenched by methylviologen band-gap excitation in the presence of Rh as catalyst and PhSH as sacrificial electron donor resulted in water photoreduction 611... 

Photoreduction of Methylviologen and Phosphotungstic Acid on CdS Colloids, the Effect of Surface Charge... 

Since the surface properties of the colloid have a strong influence on the photoreduction kinetics, it seemed interesting to elucidate the effect of the added surface-active substances on the kinetic regularities of the reactions photosensitized by semiconductor colloid. The surfactant molecules are known to concentrate near the surface of the colloidal particle, so they may affect strongly the kinetics of photocatalytic reactions proceeding at the particles surface [52,53]. Fig. 2.30 presents the temperature dependencies of the initial rate of the MV photoreduction over colloidal CdS prepared at the excess of the sulfide ions. These dependencies were obtained at the addition of different amounts of PAA. One may see that both the initial rate and the observed activation energy of the methylviologen photoreduction do not depend, within the experimental error, on the concentration of... 

Fig. 2.30. Temperature dependence of the initial rate of methylviologen photoreduction over colloidal CdS with an excess of S2 at the addition of variable PAA amounts. [CdS] = 5 10-3 M, [TG] = 5 10 2 M, [MV] = 2.5-10-4 M. Dimensionality of W is M-s l.

The second example which emphasized the electron-transfer step as a key process in polymer catalysis is the Ru(bipyridine) complex sensitized photoreduction of methylviologen, which is of interest as a means to reduce protons leading to hydrogen evolution (Scheme 3). To suppress a spontaneous backward reaction which consumes the acquired energy, a heterogeneous reaction... 

Photochemistry within a glass gas chromatographic column Photodecomposition of sulfonamides and tetracyclines Photoreduction of methylviologen adsorbed on cellulose Radiolysis of D,L-tryptophan Photolysis of dichlorofluanid... 

Such "potential" photochemical reactions can be mediated (or sensitized) by species which exhibit specific spectroscopic, redox, and excited state properties. For example, the photoreduction of methylviologen by triphenylamine takes place in the presence of Ru(bpy)3 [37] ... 

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