在解剖酶TiO2上Pt单原子协调环境的分布支持控制反应性
Wenjie Zang1, Jaeha Lee2, Peter Tieu3
1Department of Materials Science and Engineering, University of California, Irvine, CA, 92697, USA.
Nature communications
|February 2, 2024
概括
单原子催化剂 (SAC) 的反应性各不相同. 在TiO2上的白金SAC表现出不同的协调环境和可访问性,影响CO氧化性能和具有挑战性的催化剂设计.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 表面化学 表面化学
背景情况:
- 与纳米粒子相比,单原子催化剂 (SAC) 提供了高金属原子效率和独特的反应性.
- 在SAC中,结构-功能关系通常假定具有统一的活跃站点协调.
- 了解活跃站点分布对于设计高效的SAC至关重要.
研究的目的:
- 为了研究单个原子 (Pt SAs) 在解体TiO2表面上的协调环境.
- 为了将Pt SAs的位置和协调与它们的CO氧化催化活性相关联.
- 为了揭示TiO2表面面对Pt SA分散和可访问性的影响.
主要方法:
- 形状控制的解剖酶TiO2与暴露的 (001) 和 (101) 方面的合成.
- 在TiO2支架上分散单个原子.
- Pt SA协调环境和地点的特征.
- 对二氧化碳氧化催化活性的评估.
主要成果:
- 在TiO2 (101) 表面上的Pt SAs位于表面上,与现有模型保持一致.
- 在TiO2 (001) 表面上的Pt SAs在化后在表面下面被发现.
- 在 (001) 上的地表Pt SAs由于降低可访问性而表现出较低的CO氧化反应性.
- 在商业TiO2上的Pt SAs显示异质分布 (表面和散装).
结论:
- SAC的协调环境和位置不均,取决于支面.
- 地下SAC可以显著降低催化活性.
- 必须考虑SAC活性位点的异质性,以便准确的结构功能关系开发和催化剂设计.
- 这项研究强调了支表面结构在控制SAC属性的重要性.
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