订制的中孔支持的金属氧化物
Stacy M Morris1, Pasquale F Fulvio, Mietek Jaroniec
1Chemistry Department, Kent State University, Kent, Ohio 44242, USA.
Journal of the American Chemical Society
|October 17, 2008
概括
一种新的单合成产生了有序的中孔支持的金属氧化物. 这些材料提供了增强的热稳定性和大孔,非常适合催化应用.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 催化剂是一种催化剂.
背景情况:
- 开发有序的半孔材料对于先进的应用至关重要.
- 含的金属氧化物是重要的催化剂,但往往缺乏可控的多孔性.
- 现有的合成方法可能很复杂,很难复制.
研究的目的:
- 开发一种简单可重复的单合成方法,用于基支持的金属氧化物.
- 描述合成材料的结构和纹理特性.
- 为了证明该方法对各种金属氧化物的多功能性.
主要方法:
- 使用金属前体,异氧化物和triblock共聚合物结构指导剂的一自组合成.
- 包括BET表面积分析,孔隙宽度测定和X射线衍射用于对称性分析在内的特征化技术.
- 合成氧化作为一个模型系统,然后准备MgO,CaO,TiO2和Cr2O3,支持.
主要成果:
- 成功合成了具有p6毫米六角对称性的中孔支持金属氧化物.
- 实现了发达的中孔性,高的BET表面积和大孔宽度.
- 与纯相比,氧化表现出更好的热稳定性和更大的半孔孔.
- 经过长距离测定,可达到20%的含量,并成功合成其他金属氧化物.
结论:
- 一自组装方法为订购的半孔支持金属氧化物提供了方便的途径.
- 合成的材料具有理想的特性,如高表面积,大孔和增强的热稳定性.
- 这种方法是一般的,适用于一系列的金属氧化物,为先进的催化材料铺平了道路.
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