Effect of oxygen vacancies on the red phosphorescence of Sr2SnO4:Sm3+ phosphor

We reported the synthesis of a novel red long-afterglow material Sr2SnO4:Sm3+. Comparing with the air-sintered sample, a significant enhancement in both the fluorescence and phosphorescence for the vacuum-sintered sample was observed. This improvement could be attributed to the increase of oxygen vacancies which act as the sensitizer and the electron traps for the effective energy transfer from Sr2SnO4 host to Sm3+. The defects act as traps were investigated with thermoluminescence. For the presence of deep stable traps able to immobilize the energy permanently at room temperature, the Sr2SnO4:Sm3+ could be considered as a potential storage phosphor as well. (C) 2010 Optical Society of America