Abstract

Alumino-tellurite glasses with wide range of Al2O3 concentration (1 to 20-mol%) are prepared and their short-range structural and thermal properties are studied by Raman spectroscopy, 27Al Magic Angle Spinning Nuclear Magnetic Resonance (MAS-NMR) and Differential Scanning Calorimetry (DSC). Glass sample with 1-mol% of Al2O3 has TeO co-ordination of 3.66, which is close to the value of 3.68 reported in pure TeO2 glass. TeO co-ordination decreases steadily to 3.33 on increasing alumina content to 20-mol%. 27Al MAS-NMR studies found that Al ions exist in hexa, penta and tetrahedral co-ordination in the alumino-tellurite network. On increasing alumina content from 3 to 20-mol%, the concentration of hexa-co-ordinated AlO units decreases from 54% to 35% with a simultaneous increase in the concentration of penta and tetra co-ordinated AlO units. Glass transition temperature increases with increase in Al2O3 concentration and correlates directly with the average single bond enthalpy of the glass network.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.