可磁分离Fe3O4/g-C3N4复合材料的制备及其性能
Preparation and properties of magnetic separation Fe3O4/g-C3N4 composites

为了利用Fe3O4的磁响应性及石墨相C3N4（g-C3N4）优良的光催化活性，首先采用高温热聚合法，以尿素为前驱体制备g-C3N4，然后采用水热法合成了可磁分离Fe3O4/g-C3N4复合材料。利用TEM、XRD、TGA、BET和振动样品磁强计（VSM）等多种测试手段表征分析Fe3O4/g-C3N4复合材料的形貌、晶型结构、比表面积、成分、饱和磁化强度等。通过模拟太阳光下Fe3O4/g-C3N4复合材料光催化吸附降解亚甲基蓝（MB）的实验，评价了Fe3O4/g-C3N4复合材料的吸附性能及光催化性能。结果表明，可磁分离Fe3O4/g-C3N4复合材料具有较大的比表面积，约为71.89 m2/g；且具有较好的磁性，饱和磁化强度为18.79 emu/g，可实现复合材料的分离回收；光照240 min时，Fe3O4/g-C3N4复合材料对MB的去除率为56.54%。所制备的Fe3O4/g-C3N4复合材料具有优良的吸附性能、光催化活性和磁性，并可通过外加磁场进行分离与回收。 In order to utilize the magnetic responsiveness of Fe3O4 and the excellent photocatalytic activity of graphite carbon nitride (g-C3N4), high temperature thermal polymerization method was used to prepare g-C3N4 with urea as a precursor. The magnetic separation Fe3O4/g-C3N4 composite photocatalyst was synthesized by hydrothermal method. The obtained samples were characterized by TEM, XRD, TGA, BET and vibrating sample magnetometer (VSM) to investigate the morphology, crystalline phase, specific surface area, composition and saturation magnetization of Fe3O4/g-C3N4 composites. The adsorption and photocatalytic properties of Fe3O4/g-C3N4 composites were evaluated by the adsorption and photocatalytic degradation of dye methylene blue (MB) under simulated sunlight. The results show that the specific surface area of magnetic separation Fe3O4/g-C3N4 composites is large compared with g-C3N4, up to 71.89 m2/g. Fe3O4/g-C3N4 composites possess good magnetic, and the intensity of saturation magnetic field reaches to 18.79 emu/g, which is enough for magnetic separation and recovery. The removal rate of MB reaches to 56.54% under irradiation for 240 min. Fe3O4/g-C3N4 composites not only exhibit good adsorption and photocatalytic activity and magnetic, but also can be recovered easily by external magnetic field. 国家自然科学地区科学基金（21762038）；西北民族大学中央高校基本科研业务费资金（Y17125）；西北民族大学中央高校基本科研业务费专项资金（31920170022）；西北民族大学引进人才科研项目（2016035）；甘肃省重点研发计划项目（17YF1GA014）；甘肃省自然科学基金（1506RJZA267）；甘肃省科技计划项目（18 JR3RA372）