在金属有机框架中的H3O2桥接连体. 洞察水-氧氧平衡:一个结合实验和理论研究的研究
Richard F D'Vries1, Victor A de la Peña-O'Shea, Natalia Snejko
1Department of New Architectures in Materials Chemistry, Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, c/Sor Juana Inés de la Cruz, 3, 28049 Madrid, Spain.
Journal of the American Chemical Society
|March 21, 2013
概括
本研究研究了金属有机框架 (Sc-MOFs) 中的水- (O2H3) 和 (OH) 均衡. 该研究确定了热力学稳定 (O2H3) Sc-MOF 阶段及其催化应用.
科学领域:
- 材料化学 材料化学
- 超分子化学 超分子化学
- 催化剂是一种催化剂.
背景情况:
- 金属有机框架 (MOF) 是具有可调节性质的多功能材料.
- 了解MOF中的配体的物种化对于控制它们的稳定性和功能至关重要.
- 水- (O2H3) 和 (OH) 种在基于的MOF (Sc-MOF) 的水热合成和稳定性中发挥作用.
研究的目的:
- 调查Sc-MOFs中的水- (O2H3) 和 (OH) 物种之间的平衡.
- 为了确定不同Sc-MOF阶段的相对稳定性和形成条件.
- 探索合成的Sc-MOF的电子结构和催化活性.
主要方法:
- 在不同的热水条件和pH值下,Sc-MOFs的实验合成和表征.
- 计算研究 (密度函数理论) 用于计算不同物种的相对能量.
- 电子结构的分析和异质的催化试验在化的cyanosilylation.
主要成果:
- 热力学稳定阶段[Sc3{3,5-DSB) 2{μ-O2H3) 2{μ-OH) 2{H2O) 2} ((O2H3) Sc-MOF) 已经成功分离出来.
- 确定了基主导相[Sc3(3,5-DSB) 2(μ-OH) 3(H2O) 4作为前体,不能作为纯相分离.
- 为进行比较分析,报告了另外两种在不同pH值范围内出现的Sc-MOF化合物.
结论:
- 该研究阐明了Sc-MOF中的水-和基物种之间的pH依赖平衡.
- 在特定的热水条件下, (O2H3) Sc-MOF 阶段表现出优越的热力学稳定性.
- 合成的 (O2H3) Sc-MOF 在化化反应的异质催化中显示出潜力.
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