中文摘要：

采用水相共沉淀法制备小尺寸磁性Fe3O4纳米颗粒，以没食子酸作为还原剂和表面修饰剂，还原Ag[（NH3）2]’制备出Fe3O4／Ag磁性纳米颗粒。研究该磁性纳米颗粒对水溶液中铅离子的吸附行为，研究结果表明，pH为7．0，吸附温度30℃时可得到最好的处理效果，铅的去除率可达99．7％以上，Fe3O4／Ag颗粒吸附行为符合二级动力学模型（R2〉0．99）。该磁性纳米颗粒经过多次再生处理后，仍具有很好的吸附效果，表明Fe3O4／Ag在水处理方面拥有良好的应用前景。

英文摘要：

Small size Fe3O4 magnetic nanoparticles were prepared by aqueous phase coprecipitation and then the Fe3 O4/Ag core-shell nanoparticles were synthesized by reducing Ag[ （NH3 ）2 ] ＋ with gallic acid as re- ducer and surface modifier. The absorption behavior of lead ions of the nanoparticles in aqueous solution was studied. The results showed that the optimized condition of pH for metal ions removal was 7. 0 while the temper- ature was 30℃. The removal efficiency of lead was above 99.7% and the absorption kinetics for Pb2＋ was agree with the second order model （R2 〉 0.99）. Furthmore, the Fe3 O4/Ag nanoparticles could be well reusable after being regenerated, indicating that Fe3Og/Ag nanoparticles had a good prospect in water treatment.