中文摘要：

制备了一种高磁响应的Fe3O4-SiO2-Polypyrrole纳米复合核壳颗粒,并成功应用于水相体系中重金属离子Cr2O72-的吸附研究.分别采用X射线衍射仪（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、红外光谱仪（FTIR）和振动样品磁强计（VSM）对产物的结构、形貌与磁性能进行了表征,结果揭示,核壳复合吸附材料由400nm大小的Fe3O4多晶球簇内核、100nm厚度的非晶SiO2壳层以及外层聚吡咯材料组成,其饱和磁化强度为43.5emu/g.通过电感耦合等离子体发射光谱仪（ICP-AES）研究了其对重金属离子的吸附性能,按照Langmuir等温吸附模型计算的饱和吸附量为35.52mg/g.证明对于Cr2O72-离子,该核壳结构纳米材料是一种性能良好、可高效磁分离的吸附材料.

英文摘要：

Core-shell Fe3O4-SiO2-Polypyrrole nanoparticles have been prepared, and their adsorption of Cr2O7^2- ions investigated. Nanoparticle morphology and structure were characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and infrared spectroscopic techniques. Their magnetic saturation values were determined using a vibration sample magnetometer. The nanoparticle structure was composed of a polycrystalline Fe3O4 inner core （diameter -400 nm）, and outer shells of amorphous SiO2 （thickness -100 nm） and polypyrrole （thickness -100 nm）. The magnetic saturation was found to be 43.5 emu/g. The adsorption of Cr2O72 was characterized using inductively coupled plasma atomic emission spectroscopy. The maximum saturated adsorption capacity was calculated to be 35.52 mg/g, by fitting to a Langmuir adsorption isotherm model. This result suggested that the nanoparticles could be applied to Cr2O72- adsorption, with high efficiency magnetic separation.