Influence of multi valent states of vanadium ions in ZnO doped novel calcium fluoro phosphate bio glasses

Abstract

ZnO-CaF₂-P₂O₅ glasses doped with different concentrations of V₂O₅ (ranging from 0 to 1.0 mol %) were prepared. The prepared bio glasses are soaked in SBF for duration of 2, 3, 7 and 10 days in separate plastic containers and then kept in incubator maintained at body temperature 36.5 °C. The influence of valence states of vanadium ions (V⁴⁺/V⁵⁺) with respect to the structural aspects by means of FTIR and Raman Spectra, elastic properties by means of relevant parameters, the thermal stability by means of DTA studies and other spectroscopic properties by using OA and ESR studies are studied. The raise in wavenumber and comparative areas of the two absorption bands corresponding to electronic transitions 2B_2g → E_2g, 2B_2g → 2B_1g respectively in optical absorption spectra of these CZPV glasses clearly indicate that vanadium ions have octahedral co-ordination with tetragonal compression due to modifier action of V₂O₅in the glass network. The optical absorption and ESR studies have revealed that vanadium ions exist in V⁴⁺ states. The characteristic temperatures of these prepared glasses obtained from DTA curves explain modifications taking place in the structure of glass network. The structural changes are explained with the aid of FTIR and Raman studies. The bio active nature of the titled glasses is evident from dissociation and pH studies by SEM &EDS of these glasses before and after immersion into SBF.

Keywords: ESR; IR; Optical absorption; Raman; Vandium ions; ZnO–CaF(2)–P(2)O(5) glasses.