晶体面增强了低协调Pt1-TiO2单个原子物种的动态稳定性和反应性,用于甲氧化
Qi Wang1,2, Qingqing Gu1, Aiqin Wang1
1CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
二氧化 (TiO2) 的晶体方面支持显著影响单原子催化剂 (SAC) 的性能. TiO2(001) 方面促进了活跃的 Pt SACs 进行甲氧化,与不活跃的 TiO2(101) 方面不同.
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:
- 在反应过程中,单原子催化剂 (SAC) 在支晶体面上的动态演变还不太清楚.
- 了解这种演变是设计高效催化剂的关键.
研究的目的:
- 研究TiO2支的晶体面如何影响甲氧化过程中单原子催化剂 (Pt SACs) 的动态行为和反应性.
- 在反应条件下阐明Pt SACs的结构-活性关系.
主要方法:
- 利用理论和实验方法的结合来研究不同TiO2晶体面 (TiO2(001) 和TiO2(101) 上的Pt SAC.
- 在甲氧化条件下分析了Pt物种的动态进化及其与TiO2支的相互作用.
主要成果:
- TiO2 ((001) 方面促进了与Ti3+-Ov (氧空位) 部分相关的协调不足的Ptδ+物种 (0 < δ < 2) 的动态形成,形成了活跃的Ptδ+-Ov-Ti3+位点.
- 相比之下,TiO2的表面稳定了具有和协调的非活性Pt4+物种.
- 这些活跃的Ptδ+-Ov-Ti3+物种表现出对高甲氧化活性至关重要的独特动态稳定性,与热或还原稳定性不同.
- 活性位点的增强酸度促进了C-H激活和O2解离.
结论:
- 支持的晶体方面在活跃的单原子催化剂物种的动态进化和稳定中发挥着至关重要的作用.
- 特定面 (TiO2(001)) 决定了高活性Pt SACs (Ptδ+-Ov-Ti3+) 的形成,这对于甲氧化至关重要.
- 这项研究为SAC的动态稳定提供了洞察力,并提供了基于面体依赖动态演变的催化剂设计的新策略.
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