通过triblock共聚合物辅助合成形成一个新的Ia-3d立方半结构
Katarina Flodström1, Viveka Alfredsson, Niklas Källrot
1Physical Chemistry 1, Lund University, P.O. Box 124, SE- 221 00 LUND, Sweden. katarina.flodstrom@fkem1.lu.se
Journal of the American Chemical Society
|April 10, 2003
概括
研究人员合成了一种具有大型单元细胞和高表面积的新型半孔. 这种新材料表现出立方Iad对称性,可能基于状腺的最小表面.
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:
- 半孔二氧化材料在催化和分离中至关重要.
- 开发具有受控毛孔架构的新型结构是一个正在进行的研究领域.
- 现有的合成方法通常会产生较小单元细胞的结构.
研究的目的:
- 为了合成和表征一种新的半孔结构.
- 为了研究结构性质,包括对称性和单元细胞尺寸.
- 探索在半孔二氧化合成中使用酸盐的潜力.
主要方法:
- 使用triblock共聚合物 (Pluronics P103或P123) 的合成,添加化 (NaI).
- 使用小角度X射线散射 (SAXS) 来确定对称性的表征.
- 分析电子微图,以阐明孔隙结构.
- 使用气体吸附技术确定表面积.
主要成果:
- 成功合成了一种具有立方 Iad 对称性的中孔性.
- 观察到非常大的单元细胞尺寸 (高达250 Å 合成,222 Å 化).
- 实现了大约700m2/g的高表面积.
- 建议与MCM-48的结构相似性,表明状腺的最小表面.
结论:
- 将NaI添加到合成混合物中,可以形成一种具有IAD对称性的新型中性孔.
- 合成材料具有异常大的单元细胞和高表面积.
- 该结构建议基于状腺的最小表面,为材料设计提供了新的可能性.
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