Observation of Energy Transfer from Host to Rare‐Earth Ions in Ca 2 SnO 4 :Pr 3+ Phosphor

Red optical properties of Pr 3+ ‐doped Ca 2 SnO 4 compounds prepared by the solid‐state reaction at different atmospheres were investigated. Comparing with the air‐sintered phosphor, a significant enhancement of the red emission intensity was observed for the vacuum‐sintered phosphor. This improvement could be attributed to the increased oxygen vacancies, which act as the sensitizers for the effective energy transfer (ET) from Ca 2 SnO 4 host to Pr 3+ . This study demonstrated that the ET process between the host and rare‐earth ions in Ca 2 SnO 4 was closely related to the oxygen vacancies.