State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, PR China.
J Colloid Interface Sci. 2012 Nov 1;385(1):58-65. doi: 10.1016/j.jcis.2012.06.082. Epub 2012 Jul 15.
In this paper, we report the preparation of γ-Fe(2)O(3) and Fe(3)O(4) magnetic hierarchically nanostructured hollow microspheres by a solvothermal combined with precursor thermal conversion method. These γ-Fe(2)O(3) and Fe(3)O(4) magnetic hierarchically nanostructured hollow microspheres were constructed by three-dimensional self-assembly of nanosheets, forming porous nanostructures. The effects of experimental parameters including molar ratio of reactants and reaction temperature on the precursors were studied. The time-dependent experiments indicated that the Ostwald ripening was responsible for the formation of the hierarchically nanostructured hollow microspheres of the precursors. γ-Fe(2)O(3) and Fe(3)O(4) magnetic hierarchically nanostructured hollow microspheres were obtained by the thermal transformation of the precursor hollow microspheres. Both γ-Fe(2)O(3) and Fe(3)O(4) hierarchically nanostructured hollow microspheres exhibited a superparamagnetic property at room temperature and had the saturation magnetization of 44.2 and 55.4 emu/g, respectively, in the applied magnetic field of 20 KOe. Several kinds of organic pollutants including salicylic acid (SA), methylene blue (MB), and basic fuchsin (BF) were chosen as the model water pollutants to evaluate the removal abilities of γ-Fe(2)O(3) and Fe(3)O(4) magnetic hierarchically nanostructured hollow microspheres. It was found that γ-Fe(2)O(3) hierarchically nanostructured hollow microspheres showed a better adsorption ability over SA than MB and BF. However, Fe(3)O(4) hierarchically nanostructured hollow microspheres had the best performance for adsorbing MB.
本文采用溶剂热结合前驱体热转化法制备了γ-Fe(2)O(3)和 Fe(3)O(4)磁性分级纳米结构空心微球。这些γ-Fe(2)O(3)和 Fe(3)O(4)磁性分级纳米结构空心微球是由纳米片的三维自组装形成的多孔纳米结构。研究了反应物摩尔比和反应温度等实验参数对前驱体的影响。时间依赖性实验表明，奥斯特瓦尔德熟化是前驱体分级纳米结构空心微球形成的原因。通过热转化前驱体空心微球得到γ-Fe(2)O(3)和 Fe(3)O(4)磁性分级纳米结构空心微球。γ-Fe(2)O(3)和 Fe(3)O(4)分级纳米结构空心微球在室温下均表现出超顺磁性，在 20 KOe 的外磁场下饱和磁化强度分别为 44.2 和 55.4 emu/g。选择水杨酸（SA）、亚甲蓝（MB）和碱性品红（BF）等几种有机污染物作为模型水污染物，评估γ-Fe(2)O(3)和 Fe(3)O(4)磁性分级纳米结构空心微球的去除能力。结果表明，γ-Fe(2)O(3)分级纳米结构空心微球对 SA 的吸附能力优于 MB 和 BF，而 Fe(3)O(4)分级纳米结构空心微球对 MB 的吸附性能最好。
