【摘要】 采用水热法加溶胶-凝胶法制备了磁性纳米复合材料Fe₃O₄@C@TiO₂（简称FCT）和Fe₃O₄@C@TiO₂@AgBr-Ag（简称FCTA）,通过红外光谱（IR）、X-射线衍射（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）和比表面分析仪（BET）对样品进行表征.在模拟太阳光照射下，以土霉素溶液作为模拟废水，研究了FCT和FCTA的光催化性能.研究结果表明：FCT和FCTA对土霉素的光催化氧化反应均符合一级反应动力学；FCTA对土霉素的催化降解率最高可达99.8%,而FCT对土霉素的催化降解率最高为76.2%;在FCTA微观结构中，由于TiO₂掺杂了AgBr-Ag,禁带宽度变小，且金属Ag为电子受体，可加速TiO₂中光生电子-空穴对的分离；FCTA的光催化性能得到显著提高，并可通过磁铁或磁场与水体分离，易于回收再利用.更多还原

【Abstract】 Magnetic nanocomposites, Fe₃O₄@C@TiO₂（FCT for short） and Fe₃O₄@C@TiO₂@AgBr-Ag were prepared by hydrothermal method followed by sol-gel method. The samples were characterized by infrared spectroscopy（IR）, X-ray diffraction（XRD）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM） and specific surface analyzer（BET）. The photocatalytic properties of FCT and FCTA were studied with oxytetracycline solution as simulated wastewater under simulated sunlight. The photocatalytic oxidation of oxytetracycline by FCT and FCTA fitted well with the first-order reaction kinetics. The highest catalytic degradation rate of oxytetracycline by FCTA was 99.8%, while the highest catalytic degradation rate of oxytetracycline by FCT was 76.2%. In the microstructure of FCTA, TiO₂ is doped with AgBr and Ag, and its band gap becomes smaller. Furthermore, metal Ag, as an electron acceptor, can accelerate the separation of photo-induced electron-hole pairs. Therefore, the photocatalytic performance of FCTA was significantly improved. FCTA can be separated from water by magnet or magnetic field, and is easy to be recycled.更多还原