Photoluminescence and vibrational spectroscopic studies on weathered uranium oxides

摘要

Spectroscopic studies were performed both on uranium oxides as baseline and on uranium oxides artificially weathered under known laboratory conditions in air, varying humidity, carbon dioxide concentration, temperature and exposure to UV light. Spectroscopic techniques included photoluminescence and diffuse reflectance FTIR. Photoluminescence measurements were made using a Spex Fluorolog-3$+TM$/ spectrofluorometer with phosphorimeter. FTIR measurements were made using a Bomem MB157 FTIR spectrophotometer with DTGS detector and approximately 450 cm$+$MIN@1$/ cut-off and a Graseby Selector$+TM$/ diffuse reflectance accessory with special cells and diamond dust as diluent and internal standard. Weathered-related reactions involving the uranium oxides that have been studied include oxidation and the formation of hydroxides and carbonates. Data are discussed with respect to both the reactions of the uranium oxides in the study and in context of reaction chemistry and mechanisms that have been previously documented. The results will be discussed in the context of environmental monitoring.