Effect of P2O5 addition on the structural and spectroscopic properties of sodium aluminosilicate glass

Abstract

The structural and spectroscopic properties of Na 20-Al 20 3 -Si0 2-xP 20 5 glasses (x =0 to 7 mol%) are investigated. Both Raman and IR spectra reveal that discrete phosphate species ([PO 4] -3, [PO 3O 1/2] -2) with low polymerization degree can be formed in the silicate glass. These phosphate structures scavenge non-bridging oxygen ions and cations from the silicate network, resulting in an increase of the glass transition temperature. According to the Judd-Ofelt intensity parameters (Ω2,Ω4,Ω6) of Er 3+, the asymmetry of local environment around Er 3+ becomes higher, and the bond covalency between Er 3+ and O 2- decreases after P 20 5 is introduced. In the emission spectra, photoluminescence intensity increases with increasing P 20 5 concentration and the spectra are inhomogeneously broadened, revealing that the ligand electric field around Er 3+ is dramatically changed, and the glass matrix becomes disordered. © 2012 Chinese Optics Letters.