Afterglow luminescence properties and mechanism of novel orange afterglow phosphor: Ca2Sb2O7:Sm3+

A novel afterglow phosphor Ca2Sb2O7:Sm3+ with a weberite-type structure is synthesized using a solid state reaction at 1150 °C. The intense orange afterglow luminescence is first observed in antimonates (Ca2Sb2O7:Sm3+) and lasts for approximately 770 s (0.32 mcd/m2). The afterglow emissions are composed of host emission and characteristic emission lines of Sm3+. Further, the Sm3+ ions not only act as afterglow emission centers but also serve as aliovalent auxiliaries to create hole traps. The thermoluminescence indicates that at least two types of traps are created by doping Sm3+ ions, which are basically responsible for the afterglow luminescence of Ca2Sb2O7:Sm3+. Accordingly, the possible afterglow luminescence mechanism of Ca2Sb2O7:Sm3+ is proposed.