Influence of heat treatment on structure and some physical properties of lithium boro-niobate glass

Abstract

The glass composition (90 mol% Li₂B₄O₇–10 mol% Nb₂O₅) was prepared by the melt quenching technique. The quenched sample was heat treated at 480°C, 545°C and 630°C for 5 h and heat treated at 780°C with different time. The times were 5, 10, 15, 20, 28, and 36 h. The glass and glass ceramics were studied by differential thermal analysis (DTA), X-ray diffraction (XRD), and dc conductivity as a function of temperature. Lithium niobate (LiNbO₃) and lithium diborate (Li₂B₄O₇) were the main phases in glass ceramic addition to traces from LiNb₃O₈. Crystallite size of the main phases determined from the X-ray diffraction peaks are in the range <100 nm. The fraction of crystalline (LiNbO₃) phase increases with increase the heat treatment temperature and time. The relation between physical properties and structure were studied.

Keywords:

• oxide glass
• differential thermal analysis (DTA)
• X-ray diffraction (XRD)
• dc conductivity
• optical properties