Effect of proton irradiation on the structure and luminescence properties of Ce^3+-doped lithium-borophosphate glasses

Abstract

Ce3+- doped lithium borophosphate (LBPO) glasses were prepared with a melt quenching method. The structure and luminescence properties of Ce3+-doped LBPO glass after proton irradiation (API) are investigated and compared with those before proton irradiation (BPI). BO4 units and non-linear P-O-P bonds in the LBPO:Ce glass were broken after the proton irradiation, leading to the BO3 units, as well as more PO3 and PO4 units. There was a large red-shift (30 - 70 nm) of the absorption cut-off edge for the glasses after proton irradiation. A blue shift (about 10 nm) in the emission and excitation spectra was observed for the LBPO:Ce glass after proton irradiation compared with that before proton irradiation. This is due to the structure of LBPO:Ce glass and [CeOn] polyhedra becoming more flexible and larger after the proton irradiation. In addition, the integrated emission intensity decreased to about 20% for both under UV and X-ray excitation. The depths of the traps generated in the glasses during the proton irradiation process were estimated to be about 0.12 - 0.28 eV for different Ce3+ concentrations.