Organic Solvent Dispersed TiO2 Nanocrystal Sol: Synthesis and Characterization

Anatase TiO2 nanoparticles with a mean diameter of approximately 10 nm were successfully synthesized by a nonaqueous sol-gel route without the use of air-free equipment. The nanoparticles are well dispersed in common organic solvents in the form of primary particles, and the colloid is stable for more than one year. The particles and colloid were studied by X-ray diffraction (XRD), transmission electron microscope (TEM), atomic force microscopy (AFM), quasielastic light scattering (QELS), nuclear magnetic resonance (NMR) spectroscopy, and size-exclusion chromatography (SEC). The average particle size measured by several analytical methods is in excellent agreement. Moreover, NMR and SEC are able to detect the presence of an additional component comprising a second population of smaller particles with a diameter of 2 nm. The work in this paper shows that nanotechnology can benefit significantly from the new application of conventional analytical tools.