The influence of auxiliary codopants on persistent phosphor Sr2P2O7:Eu2+,R3+ (R = Y, La, Ce, Gd, Tb and Lu)

•The persistent luminescence in Sr2P2O7:Eu2+,R3+ was reported.•Sr2P2O7:Eu2+,Lu3+ shows the best performance.•The influence of auxiliary codopants was discussed in terms of ionic potential and ionic radius.

We investigate the persistent luminescence in europium-doped strontium pyrophosphate upon codoping with auxiliary rare earth ions. The persistent phosphors are synthesized via solid-state reaction method under flowing N2 + H2. Under UV irradiation, broadband emission persistent luminescence located at 420 nm is observed in all of these phosphors at room temperature. The effects of auxiliary rare earth ions on Sr2P2O7:Eu2+ are discussed according to the decay curves and thermoluminescence spectra. Sr2P2O7:Eu2+,Lu3+ shows the best performance, while and La3+ and Ce3+ codoped samples are the weakest. The influence of auxiliary codopants is discussed in terms of ionic potential and ionic radius. We derive an empirical formula based on the experimental results.

Graphical abstractRare earth ions which close to the line are good codopants.Figure optionsDownload full-size imageDownload as PowerPoint slide