具有分子排序的乙烯基组的双功能杂交半孔有机酸盐
Yongde Xia1, Wenxin Wang, Robert Mokaya
1School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
Journal of the American Chemical Society
|January 13, 2005
概括
我们合成了含有乙烯的新型混合体半孔有机酸材料,具有增强的热水稳定性. 这些材料具有分子排序的孔壁和双功能性质,可用于先进的应用.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学 有机化学
- 纳米技术纳米技术
背景情况:
- 混合中孔材料为各种应用提供可调节的性能.
- 有机酸结合了有机和无机成分的好处.
- 提高水热稳定性对于实际材料使用至关重要.
研究的目的:
- 为了合成和描述含有乙烯的新型杂交半孔有机酸盐材料.
- 研究这些材料的结构排序,多孔性和热稳定性.
- 评估乙烯添加对水热稳定性和材料功能的影响.
主要方法:
- 合成使用1,2-bis(triethoxysilyl) 乙烯 (BTEE) 作为有机 precursor 和异氧化物.
- 使用粉末X射线衍射,固态NMR ((29) Si, (13) C MAS NMR) 和拉曼光谱进行了表征.
- 在沸水中评估表面积,孔积,热稳定性和水热稳定性.
主要成果:
- 成功合成了类似晶体的,结构上有序的材料,表面积大 (>1300 m(2) / g) 和孔积大 (>1.10 cm(3) / g).
- 在框架内确认了分子排序的乙烯基组的存在,稳定高达300°C.
- 由于乙烯的结合,有机和有机酸盐材料在沸水中表现出增强的热水稳定性.
- 在由四面体协调的Al和有序的乙烯基组产生的有机酸盐材料中确定了一种双功能性特性.
结论:
- 乙烯被纳入混合的半孔有机酸中,可以改善结构秩序和增强热水稳定性.
- 合成材料表现出理想的孔隙性和热稳定性,使它们适合苛刻的应用.
- 这些材料的双功能性质为催化和吸附过程开辟了道路,这些过程需要易斯酸位和特定的有机功能.
相关概念视频
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