Synthesis of Rutile (α-TiO₂) Nanocrystals with Controlled Size and Shape by Low-Temperature Hydrolysis:  Effects of Solvent Composition

Abstract

A new methodology was developed to synthesize uniform rutile (α-TiO 2 ) nanocrystals by the thermohydrolysis of titanium(IV) chloride in hydrochloric acid−alcohol aqueous solutions at 40−90 °C. Depending on the acidity, the solvent used, and the aging temperature, rod-shaped rutile nanocrystals in sizes ranging from ∼100 nm to 800 nm were obtained. Nanocrystal size and shape are shown to be strongly and systematically related to the type and the concentration of alcohol used in the alcohol−water solvent, as well as the presence or absence of both cationic and anionic surfactants. No other titania phases, such as anatase or brookite, were detected using X-ray diffraction, transmission electron microscopy, and Raman spectroscopy.