Author(s):
Vikas Attri, M.S. Dahiya, Ashima Hooda, A. Agarwal and Satish Khasa

Abstract:
Barium-Boro-Bismuthate glasses modified with Nb2O5 and V2O5 having composition xNb2O5-(10-x)V2O5-25BaO-30B2O3-35Bi2O3 (where x = 0, 1, 3, 5, 8, 9 and 10 mol%) were prepared via melt-quench technique and investigated for structural, optical, electrical and thermal properties. The produced glasses were subjected to thermal exposure for five hours at 450 C in order to examine structural modifications inside the glass matrix. Densities of as-prepared glass samples were measured and values were found to lie in order of 5.5 g/cc. XRD profile containing broad humps for as-prepared glass samples reflected their amorphous nature, and ordered peak pattern for annealed glass samples reflected development of Bi45BO69 crystalline phase (with crystallite size < 50 nm) inside annealed glass matrix. FTIR spectroscopy helps in identification of different structural units (such as BO4, BO3, BiO6 & BiO3) inside base glass matrix. Dielectric analysis reflects usability of glass samples for high frequency signal transmission, high- temperature semi-conducting and energy storage devices. Lower value for ac conductivity (~10-5 S/m) reflects usability of glass samples towards high-voltage bearing materials (due to high resistance for electrical breakdown). Optical band-gaps (Eg) for as-prepared and annealed glass samples lie between 1.13 and 2.39 eV, suggesting their usability towards various optical and opto- electronic devices (such as absorber material in solar cells, optical fibre, lenses, filters, etc.). A non-significant change in refractive index values for as-prepared glass samples after annealing reflected enlisted these into transparent glass ceramic category. A single sharp exothermic peak in each differential thermal analysis (DTA) curve reflects nucleating ability of as-prepared glass samples.

Pages: 340-359

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