Preparation of TiO2 Coated ZnO Nanocomposite by a Two-Step Chemical Method

Abstract

Nanocrystalline TiO₂ coated ZnO particles were synthesized by a two-step chemical method, which were prepared by the polymerization of ZnO nanoparticles and followed by a sol-gel coating with a TiO₂ nanolayer. The variation in zeta potential of ZnO and TiO₂ with pH exhibited isoelectric points (IEP) at 9.3 and 3.5, respectively. The ZnO particles coated with TiO₂ nanoparticles show a uniformly dispersed morphology without any agglomeration. The average particle size of ZnO particles coated with TiO₂ particles was ca. 120-140 nm. The size of the ZnO particles was 100 nm and the size of the TiO₂ coating was below 10-20 nm. The size, morphology, composition and structure of the nanocrystalline TiO₂ coated ZnO particles were characterized by TG/DTA, XRD, SEM, EDS and TEM in detail.