Synchrotron X-ray imaging material from high quantum yield Sm3+- doped Li2O-Gd2O3-ZrO2-P2O5 glass

초록

The fabrication of phosphate glass samples utilized the melt quenching procedure to synthesize the scintillating glass for synchrotron X-ray imaging application. A comprehensive investigation of the physical, optical, structural, photoluminescence, radioluminescence properties, and X-ray imaging was conducted. The findings exhibited that the density and refractive index clearly increased with higher concentrations of Sm3+ doping. The absorption spectra revealed absorbance in the UV-Vis-NIR regions. The photoluminescence and radioluminescence spectra exhibited the strongest emission intensities at 0.50 mol % of Sm2O3, with a remarkable photoluminescence quantum yield (PLQY) of 85 %. The Sm3+ ion revealed its most intense emission peak at 600 nm, relating to the f-f transition (4G5/2 -> 6H7/2) of the Sm3+ ion. The photoluminescence (PL) emission peak of Gd3+ ions at 311 nm exhibited a decreasing trend with the concurrent increase in Sm3+ emission intensity. This variation suggests the occurrence of energy transfer from Gd3+ to Sm3+ ions. The energy transfer was further confirmed by decay time analysis (lambda Ex = 275 nm and lambda Em = 311 nm), which demonstrated a maximum energy transfer efficiency of 66.08 % at a Sm2O3 concentration of 2.00 mol%. The decay time (lambda Ex = 401 nm and lambda Em = 600 nm)of Sm3+ ion was in the millisecond range, dropping from 3.156 to 0.944 ms when increasing of Sm2O3 concentration. The Inokuti-Hirayama (IH) model (S = 6) confirms dipole-dipole interactions as the primary energy transfer mechanism among Sm3+ ions. Radioluminescence measurements revealed an integral scintillation efficiency of 55.39 % relative to the standard BGO crystal. High-resolution X-ray imaging using synchrotron radiation demonstrated a spatial resolution of 10 lp/mm and a modulation transfer function (MTF) of 0.46 at this frequency. These findings validate the potential of Sm3+- doped phosphate glass as a promising candidate for synchrotron X-ray imaging scintillators.

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