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 (TiO 2 ) 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 TiO 2 (A/R–TiO 2 ) hollow photocatalyst through in-situ growth of rutile TiO 2 on anatase TiO 2 hollow microspheres byheat treatment. The as-synthesized A/R–TiO 2 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–TiO 2 hollow photocatalyst significantly promotes efficient charge separation due to the intimate contact of two phases within a single hollow sphere. Notably, A/R–TiO 2 exhibits more efficient than commercial TiO 2 (P25) towards the photodegradation of various pesticide pollutants, which suggests that such a structural design can be an effective method for rationally constructing TiO 2 -based photocatalyst with advanced performance.