摘要
Alkaline hydrogen peroxide treatment was proposed as a simple and green way to improve the performance of commercial TiO 2 powder for water-dispersibility and visible-light photocatalytic activity on the degradation of dye pollutants. The performance of treated TiO 2 was evaluated as a function of NaOH concentration, H 2 O 2 concentration, and treatment time. The optimal conditions were determined to be 24 h in 100 mM H 2 O 2 and 8 M NaOH. The treated samples were characterized by Raman spectroscopy, high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and ultraviolet–visible spectrophotometry. The analysis revealed that the crystal structure, morphology, and absorption band gap were retained, but the surface of the treated TiO 2 was dramatically changed. The treated TiO 2 was highly dispersible with a uniform hydrodynamic size of 41 ± 12 nm and stable over months in water at pH 3 without any stabilizing ligand and could significantly enhance the visible-light photodegradation of dye pollutants. The superior performance might be attributed to the formation of abundant surface hydroxyl groups. This treatment paves the way for developing water-dispersible TiO 2 with superior visible-light induced photocatalytic degradation of dye pollutants without any complicated and expensive surface modification.