Nanocrystlline 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 approximately 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.

Keywords: Nanocrystalline, TiO2 coated ZnO, two-step chemical method, interdependent attraction.