Microstructural characterization and optical polarization of glass with needle-like micro-nano silver oriented arrangement

Homogeneous glasses in the Na2O-B2O3-Al2O3-SiO2 system doped with proper amount of AgCl were obtained by melting at a temperature of 1450 degrees C. Then, with several steps of treatment, including crystallization, elongation and reduction, the glass with oriented arrangement of needle-like micro-nano silver particles was produced. The microstructure and the optical properties of the glass samples in different stages were studied by SEM-EDAX, FE-SEM and UV-Vis spectrum. The results showed that the glass after elongation and reduction exhibits excellent polarization performance in the wavelength range from 600 nm to 900 nm, with an extinction ratio larger than 45 dB. The glass only elongated shows also slight polarizing performance, which may result from the formation of filament structure of Ag during elongation processing. (c) 2008 Elsevier B.V. All rights reserved.