Synthesis of titania microspheres with hierarchical structures and high photocatalytic activity by using nonanoic acid as the structure-directing agent

摘要

The titania, as the heterogeneous photocatalyst, has attracted much attention in attempts to eliminate pollutants, especially organic compounds in water and air. In this study, the titania microspheres with hierarchical structures were prepared by a combined sol-gel and solvothermal method. The X-ray powder diffraction (XRD) result indicated that the synthesized titania microspheres were of anatase phase. Field-emission scanning electron microscope (FESEM) and high-resolution transmission election microscope (HRTEM) showed that the microspheres with well-dispersity had an average diameter of 651 nm and were composed of nanoparticles with about 20 nm in diameter. The Brunauer-Emmett-Teller (BET) results showed that the microspheres possessed high surface areas and lots of mesopores. Further study indicated that the synthesized titania microspheres exhibited high photocatalytic activity and had an important advantage over the commercial P25.