Energy transfer between UO22+ and Eu3+ in sol-gel glasses: a spectroscopic investigation

Silica glasses doped with uranyl ions (UO22+) and europium ions (Eu3+) via sol-gel processes have been prepared so that the quenching of the UO22+ emission by Eu3+ in the sol-gel glass could be investigated. The quenching efficiency is found to be much less than that in aqueous solutions. This difference between the quenching efficiencies in the solid sol-gel glass and the liquid solutions can be attributed to that of the mobility of Eu3+ and UO22+ in two systems. A static energy-transfer process is proposed as the dominant mechanism for the quenching of UO22+ emission by Eu3+ in the sol-gel glass.