Synthesis,Characterization And Property Of Treating Organic Pollutants For BiOCl-Based Composites

BiOCl, as a semiconductor, has been studied extensively because of its layered structure, outstanding optical as well as electrical properties. It has been applied in many fields, including pharmaceuticals, pigments, catalysts and gas sensors.BiOCl and Fe/BiOCl have been successfully synthesized via a simple solvothermal technique. The microstructures of samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy(SEM), X-ray photoelectron spectroscopy (XPS) and N2 adsorption-desorption measurements. The results indicated that the obtained BiOCl micro-flowers with high specific surface area were made of accumulated nanosheets. Fe not only taken part in the synthetic process, but also induced a morphology transformation for BiOCl. The obtained samples exhibited excellent adsorption capabilities for cationic dye RhB, which reached nearly 100% within 10 min. However, they displayed poor adsorption performance toward anionic dye MO, which could be related to the surface electrical behaviors of samples. The adsorption isotherm of the BiOCl and Fe/BiOCl could be well-modeled using Langmuir isotherm. And the kinetic modeling study has shown that the experimental data were found to follow the pseudo-second-order model suggesting a chemisorption process.Using natural kaolin as the raw material, the ordered mesoporous material FCSBA-15 with enhanced hydrothermal stability was successfully synthesized in the presence of a fluorocarbon surfactant. FCSBA-15 was further used as the support for synthesizing the Fenton-like catalyst Fe/BiOCl-FCSBA-15 with the aim of exploring its catalytic performance towards the degradation of 2-nitrophenol. The results indicated that Fe existed as Fe3+ on the surface of flower-like BiOCl. The obtained Fe/BiOCl-FCSBA-15 exhibited an excellent degradation efficiency for 2-nitrophenol, which reached almost 100% within 40 min in the condition of H2O2 dosage=800 mg/L, pH value=4, T=60℃, Fe/Bi molar ratio=0.5 and Bi/Si molar ratio=0.6.Bi2O3/BiOCl heterojunction was constructed using uniform microspheres BiOCl as the self-sacrifice template by a simple alkaline treatment method. The flower-like BiOCl transformed to Bi2O3 with satellite structure assembled with nanorods during the alkaline treatment. The as-obtained Bi2O3/BiOCl heteroj unction exhibited remarkably enhanced photocatalytic performance for the degradation of MO under visible-light irradiation, which is 1.2 times and 2.5 times as that of pure BiOCl and Bi2O3, respectively. Photocurrent measurement confirmed that the formation of heterojunction between Bi2O3 and BiOCl can distinctively improve the separation efficiency of the photogenerated electron-hole pairs.Based on BiOCl, three kinds of environmental purification materials have been synthesized through introducing Fe3+, compounding with FCSBA-15 as well as in-situ synthesis of Bi2O3/BiOCl heterojunction. The three materials realized the complete removal of organic pollutants through adsorption, Fenton-like reaction and photocatalytic reaction. This investigation could not only provide a new idea for constructing excellent environmental purification materials, but also offer a theoretical support for exploring BiOCl application in more fields.