BiOI thin film (BiOI TF) was prepared via a low temperature chemical vapor transport (CVT) route for the first time, and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, fast-Fourier transform pattern and UV–vis diffuse reflectance. As-synthesized BiOI thin film was composed of high symmetrical BiOI nanosheets with dominant exposed {0 0 1} facets. It displayed better photocatalytic activity, durability and selectivity than benchmark P25 TiO 2 thin film and the origin come from the layered structure and good photoelectrochemical performance, CVT immobilization, the 100% terminal oxygen atoms of {0 0 1} facets, respectively. At end, the photocatalytic mechanism with O 2 − production was studied.
Qian Zhao,Liang Hao,Fei Li,Tongyang Liu,Yiqiang He,Jun Yang,Yifan Zhang,Yun Lu
The hydrothermal method was used to prepare flexible BiOCl-BiOI films on one stainless steel wire mesh. Nano-flower like BiOCl-BiOI crystals consisted of nanoplates were formed, and BiOCl was uniformly distributed. The XPS (X-ray photoelectron spectroscopy) spectra confirm the formation of BiOCl-BiOI heterojunction, which enhanced the visible light absorption of the BiOI film. The photocatalytic activity of the BiOCl-BiOI film in degrading RhB and MB was elevated by at most 8.7 and 2.4 times, respectively, comparing with the individual BiOI film. We designed and constructed a piezo/photocatalytic platform in which the prepared BiOCl-BiOI films were fixed on a rotating shaft. Compared with the static state, the photocatalytic activity of the BiOCl-BiOI film was increased by 1.4 times when the shaft was rotating. We believe that the enhancement of the photocatalytic activity should be ascribed to the piezoelectric field by introducing bending deformation, which accelerated the separation of photogenerated electrons and holes. The improvement mechanism of the photocatalytic and piezo/photocatalytic performance was proposed and discussed. The flexible BiOCl-BiOI heterojunction films show significant application potential in the pollution control of fluid fields such as rivers, oceans, waterfalls, and air.
BiOI powder has been proved to be an efficient photocatalyst, but the difficulty in removing it from water after reaction limits its application in real water treatment . To solve this problem, a thin-film fixed-bed reactor (TFFBR) was set-up by developing a BiOI thin film on glass fiber cloth (GFC). The composition and structure of the as-prepared films were characterized with X-ray diffraction, X-ray photoelectron spectroscopy, field emission microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy . The BiOI thin film was made by painting a silica sol containing BiOI on GFC, which could be tailored to desired sizes to accommodate the TFFBR. The mass of BiOI on the GFC increased with the number of iterations of the painting process. SiO 2 sol glued the BiOI particles tightly onto the GFC, making the thin film strong enough to resist fluid flushing in the TFFBR. The photocatalytic activity of the BiOI thin film was investigated by degrading bisphenol A (BPA) under simulated sunlight. Ninety eight percent of BPA (20 mg/L in 2 L) was degraded by the BiOI thin film sample of seven layers (GFC-7) on the TFFBR within 8 hr irradiation. The GFC-7 displayed good photocatalytic ability toward artificial sewage containing BPA in a wide pH range (5–9), and also demonstrated excellent durability and reusability. The working conditions were optimized and it was found that the thickness of the fluid film and residence time over the thin film were key factors affecting the photocatalytic efficiency.
危险品化学品经营许可证（带存储）