中文摘要：

采用溶剂热法制备出具有尺寸可调、分散性好、亲水性和超顺磁性的亚微米Fe3O4磁球,并考察了不同表面活性剂、反应时间和反应温度的影响。分别采用XRD、FE-SEM、FTIR、超导量子干涉仪（SQUID）对其结构、形貌、表面性质及磁性进行了表征。结果表明,产物为立方结构、具有单分散性的Fe3O4亚微米球,粒径在140~360nm可调。所得Fe3O4亚微米球在室温条件下的磁滞回线表现出超顺磁性,矫顽力为零。不同表面活性剂对粒径大小和磁饱和强度有一定的影响,但对其形貌和晶相结构无影响。随着反应时间的延长和反应温度的提高,颗粒粒径有逐渐减小的趋势。

英文摘要：

Size-controllable,better dispersed,hydrophilic and superparamagnetic submicron Fe3O4 spheres were perpared by a solvothermal method.Effects of surfactants,reaction time and reaction temperature on the product were examined.XRD,FTIR,FE-SEM,and superconducting quantum interface device（SQUID） were employed to characterize the Fe3O4 microspheres.The results show that Fe3O4 microshperes have a cubic structure and better dispersibility,the sizes of Fe3O4 microshperes can be controlled at 140~360 nm,the samples are superparamagnetic at room temperature and the coercivity is negligible.The surfactants have an influence on the size and saturation magnetization of the samples but have no effect on the crystalline phase structure and morphologies.With the increasing of reaction time and temperature,the size of the samples decreases.