Samarium doped calcium sulfate ultra-phosphate glasses: Structural, physical and luminescence investigations

Abstract

Luminescence mechanism of RE doped glasses is significant in optical devices, the glasses of compositions (80-x) P2O5-20CaSO4-(x) Sm2O3 with 0.3 ≤ x ≤ 1.5 mol% have been prepared by melt-quench method. The result of XRD patterns affirmed the amorphous nature of the samples. The structure was investigated successfully using FTIR, NMR and Raman in order to examine the molecular vibrational modes and to verify the de-polymerization process. Absorption and photoluminescence spectra of Sm2O3 doped calcium ultra-phosphate glasses have been reported. Three emission band of Sm3+ centered at 4G5/2→6H9/2 (642 nm), 4G5/2→6H7/2 (597 nm) and 4G5/2→6H5/2 (559 nm) have been observed at λexc = 402 nm. The spectroscopic research reveals the de-polymerization pattern in P2O5 glass structure by conversion of Q3→Q2→Q1 and to Qo units. Physical and optical properties were investigated, doped ions were successfully position at interstice spaces in CSP, the physical properties such as, density, Polarizability, Molar refractivity, and refractive index etc, have been estimated. The absorption spectra in the wavelength range 900–1700 nm were determined, the spectra consist of seven absorption peaks corresponds to transitions from 6H5/2 ground state to excited state. From the absorption edge spectra, the band gap (direct and indirect) and the Urbach energy (ΔE) values were evaluated. The conventional JO (Judd-Ofelt) intensity parameters (Ω2, Ω4 and Ω6) and root mean square (δrms) deviation have been evaluated and discussed with respect to Sm3+ concentration. Obtained result goes along with the Sm3+ doped magnesium zinc sulfo-phosphate glasses for advancement of many functional glasses.