Influence of Vanadium Oxide on the Optical and Electrical Properties of Li (Oxide or Fluoride) Borate Glasses

Abstract

Abstract Binary glass systems of the chemical composition 0.25Li 2 O–0.75B 2 O 3 and 0.25LiF–0.75B 2 O 3 with different additive ratios of V 2 O 5 were prepared using the melt-quenching method. Characterization was carried out through different techniques such as Fourier-transform infrared (FTIR) and ultraviolet–visible absorption (UV–visible) spectroscopy. Optical and electrical properties have been investigated in order to recognize the role of V 2 O 5 in glass. FTIR spectra of the studied glasses expose repetitive vibration curves with limited variations. BO 4 and BO 3 are the basic constituent units of the studied glasses in addition to the BO 2 F and BO 3 F units in the case of fluoro-borate glasses. Shifting to a higher wavelength in the optical absorption spectra and a decrease in the optical band gap values via increasing V 2 O 5 content confirms the formation of non-bridging oxygen (NBO). The ac-electrical conductivity ( σ ac ) and the dielectric constants ( ɛ ′) of the glass samples were studied in the frequency range 10 2 Hz–8 MHz. The ionic conduction takes place by Li-ion movement in all samples. The electronic conduction of borate glass can be explained using hopping between V 4+ and V 5+ . The results show excellent properties of the glass with a low concentration of vanadium oxide. Graphical Abstract