Metal free crystals, hydrogen production

After crystal illumination, spectrophotometric examination of the electrolyte by the pertitanate method (16) showed no dissolved titanium with a sensitivity on the order of 10 monolayers. It appears that no irreversible change in the surface stoichiometry of constituent elements accompanies the slow photogeneration of hydrogen on metal-free crystals in aqueous NaOH. Although a change in stoichiometry occurred in NaClOi, no such change occurs in other electrolytes which are also ineffective for hydrogen production. 

Photocatalytic and Photoelectrochemical Hydrogen Production on Strontium Titanate Single Crystals. Both metal-free and platinized samples studied in aqueous alkaline electrolytes or in the presence of NaOH-coated crystals. 391... 

A series of anhydrous and hydrated polycrystalline metal acetates has been irradiated at 77°K. with 1-Mev. electrons and the ESR spectra observed. The principal stable free radical found in the hydrated materials is methyl whereas other species predominate in the anhydrous acetates and methyl radical is not observed or is only a minor product. The absolute yield of methyl radicals, as well as the ratio of methyl to other species, appears to increase with the number of molecules of water of crystallization. The radicals obtained by breaking C-C bonds are also found in irradiated sodium perfluorosuccinate hexahydrate and acetamide and it appears that such species may be favored in crystals whose structures are largely determined by hydrogen bonding. 

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