Double bandpass filter and dual band gap study for NiO doped into P₂O₅–ZnO–Na₂O glassy system

Abstract

Glass compositions 42 P₂O₅–40ZnO–(18-x)Na₂O: xNiO in which x varies from 0 to 6 mol.% with step of 1 mol.%, are prepared by using the conventional melt annealing method. The effect of nickel ions in the investigated glass system appears in the combined structural and optical properties. Some structural and optical parameters such as molar volume, interionic distance, optical band gap, and Urbach energy are deduced. The variations in the spectroscopic data, which is affected by the deviations in composition and coordination state of nickel ions, are studied in relation to the structural evolution. The analysis of FTIR of the proposed structure shows that the local network structure is based mainly on Q ¹ and Q ² tetrahedron units connected by P–O–P linkages. Also, the optical properties show that the nickel ions occupy both tetrahedral and octahedral sites in the glass network.

Graphical Abstract

Keywords:

• Phosphate glass
• nickel ions
• structure
• FTIR
• optical absorption
• optical band gap