在Pd/TiO2中的振荡强金属支相互作用在氧化条件下
Yuhui Chen1, Jinting Hao1, Kai Zhang1
1Center of Electron Microscopy and State Key Laboratory of Silicon and Advanced Semiconductor Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
Angewandte Chemie (International ed. in English)
|April 28, 2025
概括
在Pd/TiO2纳米催化剂上的强金属支相互作用 (SMSI) 在氧化还原条件下表现出动态的振荡行为. 这种SMSI振荡影响TiO2支形态,并提供了对固态生长机制的见解.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
背景情况:
- 强金属支相互作用 (SMSI) 在催化中至关重要,但其在氧化还原条件下的动态行为尚不清楚.
- SMSI的封装对化学环境敏感,需要进一步研究其实时演变.
研究的目的:
- 在不同氧化还原条件下研究Pd/TiO2纳米催化剂上SMSI覆盖层的动态行为.
- 阐明SMSI振荡的机制及其对支形态的影响.
主要方法:
- 使用环境传输电子显微镜 (ETEM) 在现场观察SMSI动态.
- Pd/TiO2纳米催化剂被暴露在纯 O2,纯 H2 和混合 O2/H2 氧化还原大气中.
主要成果:
- 在纯O2和H2下,SMSI覆盖层形成稳定,但在0.05Pa的5:1O2/H2比下表现出振荡行为.
- 在SMSI上层的振荡中,Pd-TiO2接口附近的形成和收缩,改变了TiO2支形态.
- 该SMSI覆盖层充当了Ti物种储库,推动了支突起的生长.
结论:
- 该研究揭示了SMSI在特定的氧化还原条件下的动态和振荡性质.
- 通过Ti物种的固态生长机制,SMSI振荡在修改支形态方面发挥着作用.
- 这项工作增强了对SMSI在反应条件下的行为的理解,这对于催化剂设计至关重要.
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