Microporous Materials for Hydrogen Liquefiers and Storage Vessels

Abstract

Using the traditional melt quenching method, a zinc tellurite glass system doped with Sm3+ ions and having the following composition: [(TeO2 )0.7 (ZnO) 0.3]1-x [Sm2 O3 ] x , where x = 0.01, 0.02, 0.03, 0.04, and 0.05 molar fraction was synthesized. The structural properties of a fabricated glass system were investigated using Fourier Transform Infrared (FTIR) and X-ray diffraction (XRD) analyses. The results obtained from XRD revealed the amorphous nature of e glass system. FTIR analysis shows the bonding parameters present in the prepared glass system. The physical parameters such as density and molar volume show opposite behaviour. The UV-VIS spectroscopy was employed in order to obtain the optical properties of glass system. The optical absorption spectra were recorded in the wavelength ranging from of 200 to 2000 nm. The optical energy band gap for both direct and indirect transitions are found to be increased on increasing the content of samarium oxide. Other useful optical parameters such as refractive index, molar refraction and Urbach energy are found to be decreased. The photo luminescent spectra displays four emission spectral bands at wavelengths 566, 604, 647 and 710 nm under the excitation wavelength of 404 nm. The recorded transitions correspond to 4 G5/2 → 6 H5/2, 6 H7/2, 6 H9/2 and 6 H11/2 transitions of samarium ions respectively. The observed luminescence spectra ascertain that the studied glasses have potential to serve as laser active medium.