在Pt/TiO2上同时激活分子氧和表面晶格氧,用于低温CO氧化
Tengfei Zhang1, Peng Zheng2, Jiajian Gao3
1Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China.
Nature communications
|August 9, 2024
概括
开发先进的 (Pt) 催化剂用于低温一氧化碳 (CO) 氧化是关键. 这项研究在有缺陷的TiO2上引入了一种新的Pt-Ti金属间单原子合金 (ISAA) 和纳米粒子 (NP) 催化剂,实现了创纪录的CO氧化效率.
科学领域:
- 不同质的催化剂.
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
背景情况:
- 具有低Pt负载的高性能 (Pt) 基催化剂对于高效的一氧化碳 (CO) 氧化至关重要,特别是在100°C以下的温度下.
- 由于竞争性吸附和有限的活性位点等问题,开发这种催化剂存在重大挑战.
研究的目的:
- 设计和合成一种基于Pt的新型催化剂,具有超低的Pt负载,用于增强CO氧化.
- 研究催化机制,了解特定结构元件在低温CO氧化中的作用.
主要方法:
- 一种基于Pt的催化剂的合成,其中包括Pt-Ti金属间单原子合金 (ISAA) 和在有缺陷的TiO2支上共同支的Pt纳米粒子 (NP).
- 描述催化剂的结构和组成.
- 在低温下对CO氧化发生的催化性能的评估,包括周转频率 (TOF) 和转换率.
主要成果:
- 在80°C时实现了创纪录的高转速频率11.59s-1,只有0.15w%的Pt负载.
- 在120°C证明了完全的CO转化.
- Pt-Ti ISAA和Pt NP的共存显著改善了O2的激活,并减轻了CO和O2的竞争性吸附.
结论:
- 在缺陷的TiO2上,Pt-Ti ISAA和Pt NP之间的协同作用对低温CO氧化非常有效.
- 由 Pt-Ti ISAA 稳定的 Pt 单原子位诱导 TiO2 晶格扭曲,激活晶格氧,并使双反应通路 (Mars-van Krevelen 和 Langmuir-Hinshelwood) 实现更高的催化活性.
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