不寻常的中孔 SBA-15 具有沿短轴运行的平行通道
He Zhang1, Junming Sun, Ding Ma
1State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116023, PR China.
Journal of the American Chemical Society
|June 17, 2004
概括
研究人员合成了亚微米大小的半孔氧化SBA-15,具有立方形状的形态. 这种材料呈现出一个有序的通道结构,孔径大约为12nm.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 化学 化学 化学
背景情况:
- 半孔二氧化材料,如SBA-15,由于它们的高表面积和可调节的孔隙结构,在各种应用中至关重要.
- 控制半孔二氧化的形态和通道方向对于优化它们在催化,吸附和分离过程中的性能至关重要.
研究的目的:
- 为了合成亚微米大小的半孔氧化SBA-15,具有特定的立方体状形态.
- 调查过多的达和化 (NH4F) 对SBA-15.5的结构性质的影响.
- 为了描述合成材料的通道结构和孔径大小.
主要方法:
- 使用修改的sol-gel方法合成中孔性二氧化SBA-15.
- 在NH4F的存在下使用多余的Decane作为辅溶剂.
- 使用电子显微镜和吸附等技术,对材料的形态,结构和孔径大小进行表征.
主要成果:
- 成功制备了微微米大小的中孔性酸盐SBA-15,具有明显的立方体形态.
- 合成的SBA-15表现出一个有序的通道结构.
- 发现这些通道与立方体状粒子的短轴平行.
- 平均孔径大小被确定为大约12nm.
结论:
- 在NH4F的存在下,作为辅溶剂的过量的decane可以形成亚微米大小的立方体状半孔体SBA-15.5.
- 控制合成产生的材料具有一个有序的,平行通道系统.
- 由此产生的SBA-15材料具有其特定的形态和孔状特征,有可能在材料科学中获得先进的应用.
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