@Canageek do uranyl salts undergo photoreduction to U(IV) on exposure to visible light?
@Canageek My sole exposure (if that is the correct word to use) to any uranium chemistry is in carrying out the well-known qualitative test for sodium in solution by precipitation of the mixed acetate NaZn(UO2)3(OAc)9.6H2O, one of the very few slightly soluble sodium salts. I don't suppose anyone carries out this reaction today.
@mona Yes, but they very quickly react with H2O and O2 to go back to U(VI) :D