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

Abstract

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 Sm<inf>2</inf>O<inf>3</inf>, 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 (⁴G<inf>5/2</inf> → ⁶H<inf>7/2</inf>) 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 (λ<inf>Ex</inf> = 275 nm and λ<inf>Em</inf> = 311 nm), which demonstrated a maximum energy transfer efficiency of 66.08 % at a Sm<inf>2</inf>O<inf>3</inf> concentration of 2.00 mol%. The decay time (λ<inf>Ex</inf> = 401 nm and λ<inf>Em</inf> = 600 nm)of Sm³⁺ ion was in the millisecond range, dropping from 3.156 to 0.944 ms when increasing of Sm<inf>2</inf>O<inf>3</inf> 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.