Effect of Ca deficiencies on the photoluminescence of CaTiO3:Pr3+

The effect of different Ca deficiencies on structural and luminescent properties of the Ca1−x−yPrxTiO3 powders was investigated in this study. Ca deficiencies affect both the fluorescence intensity at 613 nm and afterglow properties of the phosphors. An increase in the fluorescence intensity at 613 nm was observed when x = 0.25 mol% and y increases from 0 to 1.5x. Similar result was found for x = 0.15 and 0.35 mol%. Increased afterglow was observed for samples having low y values after irradiated by 375 nm light. To explain the experimental results, the formation of trapping centers related to Pr3+ defects when they are not compensated by Ca vacancies was proposed based on the research works of [P. Boutinaud, E. Pinel, M. Dubois, A.P. Vink, R. Mahiou, J. Lumin. 111 (2005) 69] and [W. Jia, D. Jia, T. Rodriguez, D.R. Evans, R.S. Meltzer, W.M. Yen, J. Lumin. 119/120 (2006) 13].