Orange and red emitting long-lasting phosphors MO : Eu3+ (M = Ca, Sr, Ba)

Orange and red phosphorescence from Eu3+-activated MO (M = Ca, Sr, Ba) was clearly observed after exciting with ultraviolet (UV) light. The phosphores cence properties for CaO:Eu3+ were investigated with a fluorescence photome ter. The phosphorescence was due to D-5(0) to F-7(1) and D-5(0) to F-7(2) t ransitions of Eu3+ ions and it lasted more than 2 h. It is suggested that t rapped-electron and hole centers in the CaO host were induced by the UV lig ht and they were responsible for the generation of the long-lasting phospho rescence. (C) 2000 The Electrochemical Society. S1099-0062(00)03-006-8. All rights reserved.