Time-resolved laser fluorescence spectroscopy of UO2(CO3)34−

Abstract

The objective of the present study is to examine the luminescence characteristics of UO₂(CO₃)₃⁴⁻ in detail using time-resolved laser fluorescence spectroscopy. The peak wavelengths and lifetime of UO₂(CO₃)₃⁴⁻ were determined at room temperature using the two excitation laser wavelengths of 266 and 448 nm. The peak wavelengths in the luminescence spectrum exhibited hypsochromic shifts compared with those of UO₂²⁺. The lifetime determined from several samples containing various uranium concentrations was 8.9 ± 0.8 ns. Explanations for the hindrance to the observation of the luminescence spectrum of UO₂(CO₃)₃⁴⁻ in previous investigations are discussed. The representative experimental parameters, which might interrupt the measurement of weak luminescence, are the insertion delay time of the detection device, the overlapped luminescence of the background materials and the primary inner filter effect in the sample solution.