Visible-light photocatalytic properties and biological effects of BiOI modified using a bismuth metal-organic framework

In this work, a bismuth metal-organic framework is used as a modifier to prepare a modified BiOI photocatalytic material (BBI-2), which is then characterized via X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption isotherm, and X-ray photoelectron spectroscopy. In photocatalytic degradation tests, much higher photocatalytic activity is found for BBI-2 than for pure BiOI. After 75 min of visible-light irradiation, the degradation ratio of 10 mg/L rhodamine B by 100 mg/L BBI-2 can reach 97.14%. In addition, BBI-2 shows good performance in terms of pH applicability and circulation. Photoelectric analysis, free-radical analysis, and energy band analysis make clear that the improvement in the visible-light photocatalytic performance of BBI-2 is mainly due to the optimization of its morphology, size, specific surface area, energy band position, and the transmission and separation properties of photogenerated carriers. The active substances that play a significant role in the photocatalytic system are also determined. A study of biological effects finds that BBI-2 shows distinct photocatalytic antibacterial activity under visible-light irradiation, low cytotoxicity to human primary fibroblasts, and good compatibility with defibrinated rabbit blood.