Tailoring Mesoporous Titania Features by Ultrasound-Assisted Sol-Gel Technique: Effect of Surfactant/Titania Precursor Weight Ratio

Abstract

A mesoporous titania structure has been prepared using the ultrasound-assisted sol-gel technique in order to find out a way to tailor its structure. The TiO2 obtained was compared to the same version of titania but synthesized by a conventional sol-gel method with the objective of understanding the effect of ultrasound in the synthesis process. All synthesis experiments were focused on the preparation of a titania photocatalyst. Thus, the anatase photocatalytic active phase of titania was proven by X-ray diffraction. Additionally, the ultrasonation treatment proved to increase the crystallinity of titania samples, being one of the requirements to having good photocatalytic activity for titania. The influence of surfactant/titania precursor weight ratio on the structural (XRD), textural (N2-sorption measurements), morphological (TEM), surface chemistry (FTIR) and optical properties (UVDR) was investigated. It was observed that the crystallite size, specific surface area, band gap energy and even photocatalytic activity was affected by the synergism occurring between cavitation effect and the surfactant/titania precursor weight ratio. The study yielded interesting great results that could be considered for further application of ultrasound to tailor mesoporous titania features via sol-gel soft template synthesis, against conventional sol-gel process.