Surface Photochemistry and Miscellaneous Topics

A review (in Japanese) of the photochemistry of TiOa has been published.838 

Irradiation of high-purity ZnO in aqueous solution produces e.s.r. signals which have been assigned to unpaired electrons both in the conduction band of the bulk ZnO and in partially ionized donors (e.g. Zn+) near the surface.836 Illumination of the 2 plate in 2 electrolyte Pt cell induces photocurrents with low efficiency ( = 10-3).537 The photoreduction of methyl viologen in the presence of TiOa has been reported.838 Other studies deal with the photoreduction of Ti02 in organic media,839 and the photocatalytic deposition of Pd on Ti02.840 

The photo-oxidation of SOa to S03T in the presence of H20 and Oa or NaO has been monitored by e.s.r.841 The photo-oxidation of carbon monoxide by oxygen may be catalysed by illumination of a number of inorganic oxides,842 and in another study it has been shown that the catalytic activity of ZnO for this reaction depends on the contact time of the catalyst with the gases prior to irradiation.843 Flash illumination of TiOz initiates the dehydrogenation of methanol or ethanol to formaldehyde and acetaldehyde, respectively.844 The oxidation of paraffins and olefins to ketones takes place on irradiation of Ti02 in the presence of these 

Other subjects recently discussed include the photocoabsorption of carbon monoxide and oxygen on ZnO,664 the relative photoabsorption of oxygen and methane over ZnO,665 the photocatalytic properties of ZnO and MgO,66 the effect of irradiation on the dielectric properties of Ti02,667 the photoluminescence of an oxide layer on aluminium,668 the singlet-triplet splitting of the free A-exciton in ZnO,659 the properties of the photosensitive film of copper in iodine solution,580 and the photosensitivity of layers of CuCla and [Fe(ox)8]3-.681 

Formenti, F. Juillet, P. Meriaudeau, and S. J. Teichner, in Catalysis, Proc. International Congress, 5th , ed. J. W. Hightower, North Holland, Amsterdam, 1973, p. 1011. 

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