Photocatalytic self-cleaning properties of cotton fabrics functionalized with p-BiOI/n-TiO2 heterojunction

To endow cotton fabrics with self-cleaning property, TiO2 films were coated on the cotton fabrics by means of sol–gel method, and then BiOI nanosheets were loaded on the surface of TiO2 films by a chemical bath deposition method. The as-prepared BiOI/TiO2-cotton samples were characterized by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and UV–vis diffuse reflectance spectroscopy. The photocatalytic activity and stability of the BiOI/TiO2-cotton samples toward degradation of methyl orange (MO) solutions were evaluated. In comparison with TiO2-cotton, the dramatic enhancement in the photocatalytic performance of the BiOI/TiO2-cotton could be attributed to strong visible-light absorption of BiOI photocatalysts and the formation of a p-BiOI/n-TiO2 heterojunction. Meanwhile, the photocatalytic performances of BiOI/TiO2-cotton were maintained for the cycling experiments, indicating that BiOI/TiO2-cotton could be used as stable and efficient self-cleaning materials.