Mixed-Alkali Effect in Li2O-Na2O-K2O-B2O3 Glasses: Infrared and Optical Absorption Studies

作者：Samee M A; Edukondalu A; Ahmmad Shaik Kareem; Taqiullah Sair Md; Rahman Syed^*

来源：Journal of Electronic Materials, 2013, 42(8): 2516-2524.

DOI：10.1007/s11664-013-2605-0

• Density
• glasses
• infrared spectroscopy
• optical absorption
• band gap energy
• Urbach energy
• mixed-alkali effect

The mixed-alkali effect (MAE) has been investigated in the glass system (40 - x)Li2O-xNa(2)O-10K(2)O-50B(2)O(3) (0 mol% a parts per thousand currency sign x a parts per thousand currency sign 40 mol%) through density, modulated differential scanning calorimetry (DSC), and optical absorption studies. From the absorption studies, the values of the optical band gap (E (opt)) for direct transition and Urbach energy (Delta E) have been evaluated. The values of E (opt) and Delta E show nonlinear behavior with the compositional parameter. The density and glass-transition temperature of the present glasses also show nonlinear variation, supporting the existence of MAE. The infrared (IR) spectra of the glasses reveal the presence of three- and four-coordinated boron atoms. The specific vibrations of Li-O, Na-O, and K-O bonds were observed in the present IR study.

• 出版日期2013-8