In-situ regulation of hollow TiO2 with tunable anatase/rutile heterophase homojunction for promoting excellent photocatalytic degradation of pesticides

Constructing phase junction is an effective strategy to increase photocatalytic performance of titanium dioxide (TiO2) because it can promote charge separation. However, both low surface area and unstable phase interface limit its further application. In this investigation, we introduce a structural regulation strategy to prepare anatase/rutile TiO2 (A/R-TiO2) hollow photocatalyst through in-situ growth of rutile TiO2 on anatase TiO2 hollow microspheres byheat treatment. The as-synthesized A/R-TiO2 photocatalyst was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet-visible (UV-vis) spectroscopy. The results reveal that the A/R-TiO2 hollow photocatalyst significantly promotes efficient charge separation due to the intimate contact of two phases within a single hollow sphere. Notably, A/R-TiO2 exhibits more efficient than commercial TiO2 (P25) towards the photo degradation of various pesticide pollutants, which suggests that such a structural design can be an effective method for rationally constructing TiO2-based photocatalyst with advanced performance.