Linear Optical Properties of x PbO – 20 SiO2–10 Na2O – (70 - x) B2O3 Glass System

Abstract

Optical spectral analysis of a glass system with composition xPbO – 20 SiO2–10 Na2O – (70 - x) B2O3, where x = 20, 30, 40, 50 and 60 mol %, was studied. The investigated samples were prepared using the normal melt quench technique. The structural properties of the prepared samples were characterized using X-ray diffraction (XRD), density, molar volume and Fourier Transformation Infrared (FTIR) spectroscopy. The XRD showed the amorphous phase of the prepared samples. FTIR and molar volume results showed the formation of non-bridging oxygen in the glass network. The reflectance and transmittance were measured using two beams spectrophotometer in the spectral range of 200–2500 nm. The cutoff wavelengths of the investigated samples were increased with increase of the lead concentration. Analytical relations were used to deduce the real and imaginary refractive indices, at each scanned wavelength, from the measured reflectance and transmittance. No significant change was observed in the refractive indices with the variation of the wavelengths. Dispersive parameters of Wemple–DiDomenico dispersion’s relation were deduced. The variation of the dispersion energies was attributed to the large number of Pd+ 2 per unit volume. Optical band gap was calculated from the absorption coefficients. Its values were found in the range from 1.9 to 2.75 eV. Also, Urbach energy was evaluated and found to be in the range from 0.32 to 0.5 eV. The studied glasses possess proper optical properties, so these glasses can find applications in the optical domain.