Extended X-ray absorption fine structure (EXAFS) study of CaSO4:Dy phosphors

Extended X-ray absorption fine structure (EXAFS) measurements have been carried out on CaSO4:Dy phosphors at the Dy L3 edge with synchrotron radiation. The data have been analysed to find out the Dy–S and Dy–O bond lengths in the neighborhood of the Dy atoms. Measurements have been carried out over several samples thermally annealed for different cycles at 400 °C in air for 1 h and the change in bond lengths in samples with increasing number of annealing cycles have been studied by analyzing the EXAFS data.