直接Z型MIL-100(Fe)/BiOBr异质结的构建及光芬顿降解磺胺甲恶唑的性能

通过原位共沉淀法可控制备了系列直接Z型MIL-100(Fe)/Bi OBr异质结。使用粉末X射线衍射(PXRD)、傅里叶红外变换(FTIR)光谱、紫外可见漫反射光谱(UV-Vis DRS)、扫描电镜(SEM)、高倍透射电镜(HRTEM)以及X射线光电子能谱(XPS)对MIL-100(Fe)/Bi OBr异质结晶体结构、微观形貌、光学性能、化学组成进行表征。以低功率发光二级管可见光为光源，探究了MIL-100(Fe)/Bi OBr异质结光芬顿降解磺胺甲恶唑(SMX)性能。最佳反应体系MB-7/Vis/H₂O₂(MB-7是MIL-100(Fe)质量为Bi OBr质量的70%时制备的样品)在光源照射70 min后可降解99.8%SMX(5 mg·L^-1)。同时，还考察了H₂O₂浓度、催化剂投加量、p H值以及无机阴离子对MB-7/Vis/H₂O₂降解SMX影响。MB-7/Vis/H₂O₂能够在经过...

Direct Z-scheme MIL-100(Fe)/BiOBr heterojunctions: Construction and photo-Fenton degradation for sulfamethoxazole

A series of MIL-100(Fe)/BiOBr direct Z-scheme heterojunctions was fabricated by the in-situ precipitation method. The crystal structures, micromorphology, optical adsorption property, and chemical states were estimated by powder X-ray diffraction (PXRD), Fourier transforms infrared (FTIR) spectra, UV-Vis diffuse reflectance spectra (UV-Vis DRS), scanning electron microscopy (SEM), high-resolution transmission electron microscope (HRTEM) and X-ray photoelectron spectra (XPS). The performance of photo-Fenton degradation for sulfamethoxazole (SMX) under low-powered light emitting diode lamp irradiation was explored. The catalytic degradation efficiency of SMX (5 mg·L^-1) in the optimal reaction system (MB-7/Vis/H₂O₂, MB-7 was prepared when the mass of MIL-100 (Fe) was 70% of the mass of BiOBr) could reach 99.8% upon 70 min illumination. Meanwhile, the effects of H₂O₂ concentration, catalyst dosage, pH, and co-existing inorganic anions on SMX removal over MB-7/Vis/H₂O₂ were studied. The removal efficiency of SMX could reach above 95% after five consecutive operations, suggesting that MB-7 had good stability and reusability. The possible catalytic mechanism was unraveled by photoluminescence (PL) spectra, electrochemical measurements, radical trapping experiments, and electronic spin resonance (ESR) technique. The enhanced photo-Fenton reactivity could be attributed to the fabrication of heterostructures accelerated separation photocarriers and then induced the generation of reactive species and Fe³⁺/Fe²⁺ redox cycle.