Spectroscopic investigation of the photochemistry of uranyl-doped sol-gel glasses immersed in ethanol

Uranyl ion (UO(2)(2+)) has been doped in silica glasses through a sol-gel process. The photochemistry of UO(2)(2+) doped glasses immersed in ethanol solution has been investigated. Our experimental results indicate that UO(2)(2+) in this system can be photochemically converted to U(IV) species, and evidence is provided for the possible formation of U(IV) species via a subsequent chemical reduction of the intermediate UO(2)(+) instead of the conventional bimolecular disproportionation reaction. The latter mechanism is known to be a dominant mechanism for the photochemical reactions in homogeneous solutions.