模板法是制备无机中空微纳米球的重要方法之一。本文以苯乙烯为单体，通过乳液聚合得到粒径约为620 nm的单分散聚苯乙烯(PS)微球。以磺化后的聚苯乙烯(PSS)微球为模板，利用阴阳离子静电吸附作用，将PSS与前驱体SnSO4中的Sn2+结合。通过Sn2+在乙醇-水介质中的水解作用得到核-壳复合结构，再经高温煅烧，得到SnO2中空微纳米球。实验对前驱体的浓度、表面活性剂的用量、反应时间及模板选择等方面做了研究，通过扫描电镜(SEM)、X射线衍射(XRD)、红外(IR)光谱、热重分析(TGA)、H2程序升温还原(H2-TPR)、Brunauer-Emmett-Tel er (BET)比表面积等技术深入探究SnO2中空微纳米球的结构，并对比中空SnO2与实心粒子的氧化还原特性。 BET和H2-TPR显示将SnO2制备成微纳米空心球后其比表面积增大，表面氧空位明显增多，氧化活性明显提高。从IR及XRD推断核-壳结构形成机理，进而优化出简单合理的实验方案，获得表面光滑、结构致密，包覆厚度可控的SnO2中空微纳米球。%Templating is one of the most important methods for preparation of inorganic hol ow micro/nano spheres. We prepared monodisperse polystyrene (PS) microspheres having a diameter of 620 nm by the emulsion polymerization of styrene. Sulfonated polystyrene (PSS) microspheres were used as a template, through electrostatic adsorption of anions and cations, for modification with Sn2 + from SnSO4 precursor. The core-shel composite structures thereby produced through Sn2+ hydrolysis in an ethanol-water medium were calcined at high temperature to remove PSS and to obtain SnO2 hol ow micro/nano spheres. We investigated the effects of precursor concentration, amount of surfactant, reaction time, and templates choice. Scanning electron microscopy (SEM), X-ray diffraction (XRD), infrared (IR) spectroscopy, thermogravimetric analysis (TGA), H2 temperature programmed reduction (H2-TPR), Brunauer-Emmett-Tel er (BET) measurement, and other technical probes were used to detect the structure and properties of the prepared SnO2 hol ow micro/nano spheres, and compared them with those of solid SnO2. BET and H2-TPR showed that the hol ow SnO2 micro/nano spheres had improved specific surface area, surface oxygen vacancies, and oxidation activity. We inferred the growth mechanism of the core-shel structure from IR spectroscopy and XRD pattern and optimized the simple and reasonable synthesis procedure to obtain SnO2 hol ow micro/nano spheres which had smooth surface, compact structure, and wel control ed cladding thickness.
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