Luminescence and structural properties of Eu3+-doped calcium fluoride-bismuth oxide-phosphate glasses

Abstract

Calcium fluoride-bismuth oxide-phosphate glass of (60-x)P2O5–25Bi2O3–14CaF2–1Sb2O3-xEu2O3 (PBCFS), (x = 0, 0.25, 0.5, 0.75, and 1 mol%) was manufactured by melt-quenching technique. XRD and FT-IR spectra were obtained to characterize the PBCFS glass structure. The glass density, molar volume, refractive index, and thermal properties were determined. The absorption spectra of the PBCFS glass had three absorption peaks. The absorption peak with the highest intensity corresponded to the electronic transition of 7F0→5L6 (~392 nm), and the electronic transition starting from the first excited state (7F1) was also found. The excitation spectra corresponding to the 5D0→7F2 transition of Eu0.5 at 612 nm was obtained. When excited by a λex = 392 nm xenon lamp, the strongest orange-red emission occurred at 612 nm (5D0→7F2). According to the CIE1931 chromaticity coordinates, the chromaticity coordinates of the PBCFS glass with different Eu2O3 contents were determined by the emission spectra. The decay curve of Eu3+ ions with 5D0→7F2 (612 nm) transition was obtained by monitoring the excitation at λex = 392 nm, which was compared with other Eu3+-doped luminescent glass. The color tunability of the orange-red light emission of the Eu3+ ions indicated that Eu3+-doped PBCFS glass may be suitable for LEDs and display device applications.