Correlation between physical and structural properties of Co2+ doped mixed alkali zinc borate glasses

• Published in: Journal of non-crystalline solids 2011-09, Vol.357 (18), p.3373-3380
• Main Authors: Rao, T. Raghavendra, Reddy, Ch. Venkata, Krishna, Ch. Rama, Thampy, U.S. Udayachandran, Raju, R. Ramesh, Rao, P. Sambasiva, Ravikumar, R.V.S.S.N.
• Format: Article
• Language: English
• Subjects: Co2+ ions; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Correlation; Density; Diffusivity; Electronics; Energy gap; Exact sciences and technology; FT-IR; Glass; Mixed alkali effect; Mixed alkali zinc borate glasses; Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity; Optical properties; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Physical; Physics; Spectra
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2011.06.004

The physical and structural properties of Co2+ doped 20ZnO+xLi2O+(30−x)Na2O+50B2O3 (5≤×≤25) (ZLNB) glasses have been studied and correlated. The physical and structural parameters of all the glasses are evaluated and a non-linear behavior is observed. No sharp peaks are observed in XRD patterns of the glass samples which confirm the amorphous nature. FT-IR spectra of ZLNB glasses reveal diborate units in borate network. The optical absorption spectra suggest the site symmetry of Co2+ in the glasses is near octahedral. Crystal field and inter-electronic repulsion parameters are also evaluated. The optical band gap and Urbach energies exhibit the mixed alkali effect. All the samples are found to be strong and stable in structure with low values of Urbach energy which lie between 0.027eV and 0.039eV. The correlation between densities and Urbach energies of Co2+ doped ZLNB glasses with respect to Li2O content suggest a changeover conduction mechanism from electronic to ionic, with a diffusivity crossover point at x=15mol%. ► In the present investigation various physical and structural parameters are evaluated and correlated. ► ZLNB-3 and ZLNB-4 glass systems may be used as N-type and P-type semiconducting materials in solid-state devices. ► The optical absorption and FT-IR spectrum confirm the structural stability of ZLNB glass systems.MAE is observed. ► The correlated physical and structural properties indicates that the structural stability is very strong at x=15mol%.