通过混合集群来形成Ir/MoO接口的高密度形成,用于化学选择性酸化
Shun Hayashi1, Tetsuya Shishido2,3,4
1Division of Physical Sciences, Department of Science and Engineering, National Museum of Nature and Science, Ibaraki 305-0005, Japan.
ACS organic & inorganic Au
|October 9, 2023
概括
一种新的混合集群方法可以创建高密度的- (Ir-Mo) 接口点. 这种催化剂由于其独特的接口特性,与传统催化剂不同,可以选择性地化基.
科学领域:
- 不同质的催化剂.
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 开发具有高密度活性位点的高效催化剂对于选择性化学转化至关重要.
- 金属氧化物接口在催化活性和选择性中起着至关重要的作用.
- 现有的方法往往难以实现特定界面活性位点的高密度.
研究的目的:
- 开发一种新的催化剂制备方法,用于形成高密度金属/氧化物界面活性位.
- 为了研究一种- (Ir-Mo) 杂交聚类催化剂的选择性化的催化性能.
- 阐明控制催化剂选择性的结构-活性关系.
主要方法:
- 合成一个Ir-Mo混合集群催化剂,使用一个[(IrCp*) 4Mo4O16]前体 (Cp* = η5-C5Me5).
- 在4-尼托烯的化过程中对催化选择性的评估.
- 在不同的Ir负载下与共浸的Ir-Mo催化剂和Ir/MoO3进行比较.
- 在现场X射线吸收光谱 (XAS) 探测接口电子结构并确定氧气空缺.
主要成果:
- 混合集群的Ir-Mo催化剂在4 - 尼托基化中显示出对基组减少的高选择性.
- 相比之下,同浸的Ir-Mo催化剂显示了和乙烯基组的非选择性减少.
- 混合催化剂即使在高IR负荷 (5重 %) 中也保持了高选择性,与需要低负荷 (<0.3重 %) 的Ir/MoO3不同.
- 在现场XAS揭示了H2下的Ir/MoO接口上氧气空缺的形成.
结论:
- 高密度的Ir/MoO接口,通过混合聚类来促进,是选择性基组化的关键.
- 在界面氧气空隙上,基的优先吸附增强了选择性.
- 混合集群方法为设计具有量身定制接口特性的先进异质催化剂提供了一个有前途的途径.
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