【作者】 向炜成；

【导师】 徐瑞芬；

【作者基本信息】 北京化工大学 ， 材料科学与工程， 2012， 硕士

【摘要】 纳米半导体材料以其优异的声光电磁效应，受到研究者们的广泛关注。空心、核壳结构的TiO₂纳米半导体材料，具有密度低、比表面积大等特点，在光催化、太阳能电池、废水处理等领域应用前景广阔。结晶度高的掺铈YAG微球，是制备白光LED的理想黄色荧光粉。通过优化半导体材料的结构以改善材料性能是广大研究者新的课题。虽然已有众多这方面的工作，但将具有特殊结构的纳米材料成功应用于生产生活的实例仍然较少，主要原因之一是制备工艺复杂，难以大规模生产。针对于此，本课题主要开展了以下工作：1.以钛酸四丁酯（TBOT）为前驱体，利用两步法水热合成了高比表面积介孔TiO₂空心球。系统研究了其对Cr⁶⁺的吸附特性，包括溶液pH值、吸附剂添加量、等温吸附曲线以及与Cr³⁺共存对吸附特性的影响。探讨了其吸附类型和重复利用能力。2.以硫酸钛为前驱体，水和乙醇为溶剂，通过水热法成功制备了锐钛矿型TiO₂空心球。分析了空心结构的形成机理，详细研究了产品的光催化特性。该反应具有操作便捷、反应时间短、无需任何添加剂的优点。3.以硫酸铁为铁源，硫酸钛为钛前驱体不使用任何模板，成功制备了Fe³⁺掺杂的TiO₂空心球。对产物进行了XRD、SEM、TEM、Raman等多种表征，利用Uv-vis DRS、PL分析了产物的光学特性，评价了不同Fe³⁺掺杂比例产物光降解甲基橙的特性。4.以硝酸铝、硝酸铈、硝酸钇的混合水溶液为原料，不添加任何添加剂，利用高频热等离子体技术合成了单分散YAG:Ce³⁺微球。详细研究了产物的晶体结构、形貌、生长机理以及发射光谱强度与掺杂量之间的关系。更多还原

【Abstract】 Nano semiconductor materials have attracted so much attention becauseof its excellent properties in optics, electrics, magnetics, chemistry, etc.Forming the special nanostructure and morphologies to improve the properityof the products has become the scientist’s important task. TiO₂owns hollow orcore-shell structure, would be widely used in many fields, such asphotocatalysis, solar cell, waste water treatment, and so on, because of its highspecific surface and low density. The micro spherical YAG:Ce³⁺powders withhigh crystallinity was thought to be the best yellow phosphor for white lightLED. In addition, although the research has been done very widely, the nanomaterial with special structure used in practice is very limited for itscomplicated producing process and it’s poor yield. In this paper, the worksbelow have been done.1. Porous hollow TiO₂spheres with a high BET surface were synthesizedby hydrothermal method with two steps，in which TBOT was used as theprecursor. The adsorption results of the product to Cr⁶⁺was studiedsystematically, such as pH, sorbent concentration, adsorption isothermal curve,adsorption model, recycle capability, the effect by Cr⁽（3+）and so on. 2. Hollow TiO₂spheres have been synthesized by hydrothermal methodwith water and ethanol as the solvent, and the titanium sulfate as the precursor.The forming mechanism of the hollow TiO₂spheres was analysized, and thephoto catalysis was researched systematically. Compared with other methods,this method is very facile, in which no additive were used.3. Hollow TiO₂spheres doped wih Fe³⁺were synthesized in hydrothermalsystem without any templete. Fe₂（SO₄）₃was used as Fe³⁺precursor. XRD、SEM、TEM、Raman were used to characterized the products, and Uv-visDRS、PL were used to evaluated its optics performance.4. Monodisperse YAG:Ce3+microspheres were synthesized byradio-frequency （RF） thermal plasma using the aqueous solution of aluminumnitrates, yttrium nitrates and cerium nitrates as the starting materials withoutany additives. The phase structure, morphology, growth mechanism, andluminescence properties of the synthesized YAG:Ce³⁺microspheres withdifferent Ce3+doping amount have been investigated in detail.更多还原