Mustansiriyah Journal of Pure and Applied Sciences

Effects of Cs-137 radiation on hydrophobic silica monolithic prepared by two precursors

Ghufran Waleed Mohammed

Israa F. Al-sharuee

Muhanad Alrakabi

Keywords: Silica aerogel, Cs-137, FTIR spectroscopy, radiation, ambient pressure

Abstract

Cesium (Cs-137) radiation energy was shined on two aerogel samples made from two different starting materials at room temperature and pressure three times a day for one hour, two hours, and twenty-four hours. G1 and G2 were used as silicic acid sources to fabricate the two different types of aerogel samples. G1 represents tetraethyl orthosilicate (TEOS), while G2 represents sodium silicate (Na₂SiO₃). Field emission scanning electron microscopy analysis revealed the morphological characteristics of the molecular bonds and the impact of irradiation on them. Fourier-transform infrared spectroscopy investigated the molecular bonds and their characterization before and after exposure to radiation. The samples made from TEOS at room temperature and pressure were not affected by radiation in either the FTIR or FESEM tests. However, the samples made from Na₂SiO₃ at room temperature and pressure showed that some of the peaks were disappearing because they were exposed to radiation. Also, the peaks of the CH₃ functional group are associated with the hydrophobicity of the material. The homogeneity and uniformity for all samples are dominant, and the size of the colloidal particles is about 30-33 nanometers (nanometer structure), which is no different from the size of the particles before and after exposure to gamma rays.