Optical, infrared and electrical conductivity of glasses in the TeO2-B2O3 system

• Published in: Journal of materials science 1995-01, Vol.30 (15), p.3930-3935
• Main Authors: SABRY, A. I, EL-SAMANOUDY, M. M
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conductivity phenomena in semiconductors and insulators; Disordered solids; Electronic transport in condensed matter; Exact sciences and technology; Infrared and raman spectra and scattering; Low-field transport and mobility; piezoresistance; Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity); Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Physics
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/BF01153959

Infrared (IR) and optical absorption spectra were measured in order to study the structure of some tellurite glasses containing boric oxide. The compositions (mol%) were (100-X)TeO2, XB2O3 where X = 5, 10, 20, 25, 30. The optical spectra were measured at room temperature in the wavelength range 350-450 nm, and the results show that the fundamental absorption edge is a function of composition, with the optical absorption due to indirect transitions. The optical band gap increases with increasing B2O3 content. The validity of the Urbach rule was investigated. The IR results prove the distribution of the TeO4 polyhedra which determines the network and the basic oscillations of the building units in the tellurite glasses. The IR results also prove the distribution of the boroxal group. The electrical conductivity was measured as a function of temperature in the temperature range 300-573 K. Both the conductivity and activation energy were found to be a function of added oxide type. 26 refs.