Effect of the TiO2 shell thickness on the photocatalytic activity with ZnO/TiO2 core/shell nanorod microspheres

TiO2 shell has been fabricated directly on the surface ZnO nanorod microspheres by thermal decomposition of tetrabutyl titanate in octadecane. The thickness of the coverage with TiO2 was controlled by the amount of tetrabutyl titanate added. The core/shell nanorods have anatase TiO2 shells after annealed at 873 K in air. This method enables us to tailor the thickness of TiO2 shell for desired photooxidation application in phenol degradation. ZnO nanorods showed a relatively low efficiency in the photooxidation reaction of phenol. After coating atanase TiO2, the photocatalytic activity of the ZnO/TiO2 core/shell nanocomposites was significantly enhanced in photocatalytic degradation of phenol. It was also found that the thickness of the TiO2 shell affected the catalytic efficiency of ZnO/TiO2 core/shell nanorod microspheres.