原子分散型Pt1-多氧金属催化剂:金属支相互作用如何影响稳定性和化活性?
Bin Zhang1, Geng Sun2, Shipeng Ding1
1Department of Chemical and Biomolecular Engineering , National University of Singapore , 4 Engineering Drive 4 , 117585 Singapore.
Journal of the American Chemical Society
|April 30, 2019
概括
支持的单原子催化剂 (SAC) 在多氧金属酸盐上具有高稳定性和活性. 这些SAC在化反应中提供了更好的性能,而不会损害催化功率.
科学领域:
- 不同质的催化
- 材料科学
- 表面化学
背景情况:
- 支持的单原子催化剂 (SAC) 具有原子分散的金属原子,导致显著的金属支持相互作用.
- 了解这些相互作用的稳定性和催化作用对于设计先进催化剂至关重要.
研究的目的:
- 在多氧金属支上定量研究 (Pt) 原子的稳定性.
- 阐明Pt-支持相互作用如何影响化反应中的催化性能.
主要方法:
- 聚氧甲支持的Pt催化剂的合成和表征.
- 在化反应中对催化性能进行实验评估.
- 密度函数理论 (DFT) 计算以模拟反应路径和能量.
主要成果:
- 聚氧甲酸的Pt原子在4倍空洞点上优先吸附,最低吸附能量为5.50 eV,确保了烧结阻力.
- 在化反应中的催化活性显示出类似的途径和低效障碍 (24 kJ/mol) 在不同的Pt支持相互作用中.
- DFT证实反应仅发生在Pt原子上,通过分子吸附的H2进行化,并在SAC上进行较弱的H2吸附.
结论:
- 在不牺牲催化活性的情况下,可以在聚氧金属酸盐上获得高度稳定的SAC.
- 与集群或表面相比,观察到的低激活障碍归因于Pt SACs上的H2吸附能力较弱.
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