Preparation and characterization of bioactive silica derived from Rice husk supported TiO2 and cobalt nanocomposite via sol – gel route

Abstract

In the present study, amorphous silica nano particles were taken from low cost rice husk by carrying out an acid treatment by the process of heat treatment. Silicon precursor was obtained in the form of sodium silicate rice husk ash. Sodium silicate solution was obtained by direct silica extraction from rice husk via solvent extraction method without adding any template. The target nano composite (RHS/TiO₂/Co) was formed by embedding the cobalt nanoparticles into SiO₂/TiO₂. The prepared samples were characterized by XRD,FTIR, SEM/EDS, TG-DTA,UV and TEM. The cobalt was found to isomorphouslysubstitute in the silica matrix. A good dispersion of cobalt nanoparticles was evidenced by X-ray diffraction. Scanning electron microscopy confirmed the formation of well dispersed and spherical cobalt nanoparticles. During TGA analysis, it was observed that, mass trace suddenly goes backwards along the abscissa and then continues forward normally. This technique provided an environmentally friendly production process for conversion of waste rice husk to high performance materials.