Luminescent Properties of ${\rm Eu}^{3+}$-activated $(70\hbox{-}x){{\rm B}_2}{\rm O}_3\hbox{-}x{\rm GeO}_2\hbox{-}{{\rm Gd}_2}{\rm O}_3$ Scintillating Glasses

Abstract

Borogermanate scintillating glasses with nominal composition of (70-x)B2O3-xGeO2-29Gd2O3-1Eu2O3 (20 ≤ x ≤ 45) were synthesized by melt-quenching method. Their structure and optical properties were characterized by transmittance spectra, Fourier transform infrared spectra (FTIR), Raman spectra, excitation and emission spectra, and X-ray excited luminescence (XEL) spectra in detail. Transparency of the as-synthesized borogermanate glasses exceeds 80% in 400-800 nm regions. The cut-off edges of borogermanate glasses are in the vicinity of 308 nm, and they shift towards longer wavelength (red-shifted) with the elevated x values. Both glass density and mean molecular weight increase in a linear relationship with increasing x values. With increasing x values, the characteristic emission intensity of both Gd3+ and Eu3+ ions decrease progressively under 276 nm excitation, while these emission intensities seem irregular under 394 nm excitation. The strongest X-ray excited luminescence (XEL) intensity occurs at x = 35 glass sample, which is improved about 35% with comparison to the x = 20 one. Additionally, the information on glass structure is also discussed by FTIR and Raman spectra.