Stabilizer-free low-acid rapid synthesis of highly stable transparent aqueous titania nano sol and its photocatalytic activity

摘要

A rapid method of synthesis is reported to obtain highly stable, transparent TiO2 aqueous nano sol. The sol has been prepared using alkoxide precursor in the presence of different acids such as hydrochloric acid, acetic acid, and citric acid without using any additional stabilizer. The influence of sol-gel synthesis parameters such as inhibition ratio, hydrolysis ratio and sequence of addition of different reactants on the stability of resultant sol was investigated. Using this method, TiO2 nano sols with a low inhibition ratio (<0.57) and a high hydrolysis ratio (>5000) could be realized with storage stability of >2 years. The characterization of the sols confirmed the formation of sufficiently anatase phase, pebble like titania nanoparticles with an average diameter of similar to 4 nm as confirmed by Transmission electron microscope (TEM) and Small angle x-ray scattering (SAXS). Also, the titania nano sol finished cotton fabric exhibited self-cleaning activity of similar to 80% initially and similar to 60% after 25 washes against photostable Solophenyl green dye under UV irradiation. (C) 2020 Published by Elsevier B.V.