Non-metals B, N, P and I were doped into titanium dioxide (TiO2) to form photocatalyst particles. TiO2 doped with various ratios of B, N, P and I were thus formed and these photocatalyst particles were bonded to fix each other in a column system under sunlight as a result of the photocatalytic degradation of bisphenol A (BPA). The doped TiO2 was characterized by X-ray diffraction (XRD), UV-visible absorption spectroscopy, and X-ray photoelectron spectroscopy (XPS) to elucidate the mechanism of doping reaction. Doping with B, N, P and I to form the photocatalyst greatly red-shifted the absorption wavelength, increasing the effectiveness of the photocatalyst in reducing BPA. XPS analysis following doping revealed the bonding of B, N, P, I and other functional groups of the surface of the photocatalyst. Results of an experiment that involved the photocatalysts revealed that BPA degradations of 88%, 94%, 93% and 100% in 66.5 min under sunlight using B, N, P, and I-doped titanium dioxide, respectively. The doped photocatalysts were all superior to the undoped titanium dioxide.
Keywords: Non-metal doping; bisphenol A; photocatalysis; sunlight; titanium dioxide.