Formation of Monodisperse TiO2 nanoparticles Generated without HPC Dispersant by Controlling Reaction Method and Temperature

Abstract

Monodisperse TiO2 nanoparticles were synthesized from tetraethyl orthotitanate (TEOT) dissolved in ethanol using a semibatch method, which is easier than a batch process in controlling the size, shape, and size distribution, without the addition of HPC. In this semibatch system, the preparation conditions of a low flow rate (1.1 cc/min) and high reaction temperature (70 degrees C) were applied to produce monodisperse nanoparticles. As a result, the smallest size nanoparticles (similar to 12.7 nm in diameter) with a narrow size distribution were produced. Tn addition, it was found that the semibatch reaction had an advantage of a short nucleation due to the repetitive addition of the TEOT solution and a high temperature, at which point the solubility of the solute increased, thereby decreasing the particle size. In conclusion, the efficacy of nanoparticle synthesis was established by controlling the reaction method and temperature.