Electrical properties of SrBi2(Nb0.7V0.3)2O9− in the SrO–Bi2O3–0.7Nb2O5–0.3V2O5–Li2B4O7 glass system

Abstract Glasses in the system (100 − x )Li 2 B 4 O 7 – x (SrO–Bi 2 O 3 –0.7Nb 2 O 5 –0.3V 2 O 5 ) (where x = 10, 30 and 50, in molar ratio) were fabricated via melt quenching technique. The compositional dependence of the glass transition ( T g ) and crystallization ( T cr ) temperatures was determined by differential thermal analysis. The as-quenched glasses on heat-treatment at 783 K for 6 h yielded monophasic crystalline strontium bismuth niobate doped with vanadium (SrBi 2 (Nb 0.7 V 0.3 ) 2 O 9− δ (SBVN)) in lithium borate (Li 2 B 4 O 7 (LBO)) glass matrix. The formation of nanocrystalline layered perovskite SBVN phase was preceded by the fluorite phase as established by both the X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The dielectric constants for both the as-quenched glass and glass–nanocrystal composite increased with increasing temperature in the 300–873 K range, exhibiting a maximum in the vicinity of the crystallization temperature of the host glass matrix. The electrical behavior of the glasses and glass–nanocrystal composites was characterized using impedance spectroscopy.