Luminescence properties of Ce3 +-doped lithium borophosphate glasses and their correlations with the optical basicity

Abstract

Ce3+-doped lithium borophosphate glasses were prepared by melt quenching method, their luminescence properties were investigated by excitation and emission spectra, as well as X-ray excited luminescence (XEL) spectra. The broad emission band with the maximum center around 338nm attributing to 5d–4f transitions of Ce3+ ions is observed, and the optimal concentration of CeO2 is found to be 0.75wt.% in the CeO2-doped 57.5Li2O–5B2O3–37.5P2O5 scintillating glasses. Both the excitation and emission bands show a red shift in the 45Li2O–yB2O3–(55-y) P2O5–0.75wt.% CeO2 glasses due to the increasing value of the optical basicity with the increase of y. Moreover, the strongest XEL intensity of 45Li2O–yB2O3–(55-y)P2O5–0.75wt.% CeO2 glasses reaches a maximum at y=16.5, which might be associated with the decreasing concentration of the non-bridging oxygen and the change ratio between BO4 groups and total amount of borate groups by increasing B2O3. From the standpoints of the high Li+ concentration and fast fluorescence decay time (28.5ns), Ce3+-doped lithium borophosphate glasses are potential candidates for neutron detection.