Abstract
Two sets of tellurium-based glasses doped with vanadium and vanadium-cobalt oxides have been prepared by melt quench method and investigated for density, glass-transition temperature, specific-heat capacity and dc electrical conductivity in the temperature range 300–500 K. Thermal stability, fragility and glass-forming tendency in these systems have been estimated. Thermal stability of these glasses was found to be larger than for similar systems. The dc electrical conductivity has been analyzed in the light of Mott's small polaron hopping (SPH) and Mott's and Greave's variable range hopping (VRH) models. The electrical conduction was confirmed to be due to non-adiabatic SPH. The conductivity behavior at temperatures above TD (=θD/2) (where θD is Debye's temperature) was found to be in agreement with Mott's SPH model and at low temperatures behaved in accordance with Mott's VRH model. The temperature regions in which Mott's SPH and VRH models hold for the present systems are found to be different from similar systems already reported. Various physical parameters in these models such as, activation energy, polaron hopping energy, etc., were determined. It is for the first time that the above-mentioned properties have been investigated for the present mixed transition-metal ions-doped glasses.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
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.