Effect of CuO on the structure and properties of (50− x/2)Na 2O xCuO(50− x/2)P 2O 5 glasses

Abstract

(50− x/2)Na 2O xCuO(50− x/2)P 2O 5 glasses (5≤ x≤33.33) have been synthesized and investigated by Fourier transform infrared (FT-IR) and Raman spectroscopies. FT-IR and Raman spectral investigations reveal the formation of POCu bonds and show the evolution of the phosphate skeleton: (PO 3) ∞ chains for NaPO 3 to P 2O 7 4− groups in the richest CuO glass. The formation of POCu bonds increases the cross-link density in the glass network and therefore increases T g of the glasses. The improvement in chemical durability with increasing CuO addition is attributed to the replacement of POP bonds in the glass by more hydratation resistant POCu bonds and to the strong cross-linking of the phosphate chains by the copper ions.