复合软模板法可控制备红毛丹状AlOOH/Al_2O_3纳米材料

Controllable Preparation of Rambutan-Shape AlOOH/Al_2O_3Nanomaterials with a Composite Soft Template

以Al(NO3)3为铝源,尿素为均相沉淀剂,在聚乙二醇4000(PEG4000)-DL-天冬氨酸形成的复合软模板体系中,通过简单的常压回流方式成功合成出形貌和尺寸较为均一的红毛丹状γ-AlOOH纳米结构,继而考察了反应物和添加剂用量对前驱体形貌和尺寸的影响,并对γ-AlOOH纳米结构可能的形成机理进行了探讨.实验结果表明,所合成的红毛丹状γ-AlOOH具有球中球的核壳结构,统计得内球直径约为400 nm,外壳外径约为600nm,密集状态的壳层厚度约为15 nm,毛刺状凸出物长度可达60 nm以上.前驱体样品经600°C煅烧5 h后即转变为具有良好形貌继承性的γ-Al2O3,Brunauer-Emmett-Teller(BET)N2吸附-脱附实验表明其比表面积高达299.97 m2·g-1.

Using PEG4000-DL-aspartic acid as a composite soft template, Al（NO3）3 as an aluminum source and urea as an alkali source, homogeneous rambutan-shaped AIOOH nanomaterials were successfully synthesized by a simple heating method under atmospheric conditions. The effects of the concentrations of reactants and additives on the morphology and size of the particles were studied and the possible formation mechanism of the y-AIOOH nanostructures was explored. The rambutan-like y-AIOOH particles had a core-shell structure resembling a ball within a ball. Based on the statistical results from SEM images of the particles, the ball diameter, external diameter, shell thickness and length of burr-like projections were about 400,600, 15 and 60 nm, respectively. Results indicate that y-Al2O3 retained the morphology of the AIOOH precursor following calcination at 600 ℃ for 5 h. Brunauer-Emmett-Teller （BET） N2-adsorption experiments showed that the specific surface area of rambutan-shaped y-Al2O3 reached as high as 299.97 m2.g-1.