合金使得高效的酒精水解氧化,支持双金属催化剂
Christian Ehinger1, Stephan Pollitt2, Jordan De Jesus Silva1
1D-CHAB, ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Switzerland ccoperet@ethz.ch.
Chemical science
|March 7, 2025
概括
含有 (Mo) 和像Ir,Rh或Pt这样的金属的双金属催化剂在酒精的氧化 (HDO) 中表现出高活性. 特定的金属影响MoMo.
科学领域:
- 不同质的催化剂.
- 表面有机金属化学
- 材料科学是一种材料科学.
背景情况:
- 氧化 (HDO) 对于提升氧化碳化合物的质量至关重要.
- 双金属催化剂提供可调节的特性,以提高催化性能.
- 在双金属系统中,像 (Mo) 这样的促进剂的作用需要进一步阐明.
研究的目的:
- 通过表面有机金属化学合成和表征双金属催化剂 (M-Mo/SiO2,M = Ni,Rh,Pd,Ir,Pt).
- 评估这些材料的催化活性,以对酒精水解氧化 (HDO) 进行评估.
- 调查结构演变和Mo在催化过程中的特定作用.
主要方法:
- 在无空气条件下通过表面有机金属化学合成.
- 催化评估初级,二级和三级酒精的氧化.
- 使用 (S) TEM,IR,XAS (XANES,EXAFS) 和CO化学吸收的结构和电子表征.
主要成果:
- 对于所有类型的酒精,Ir-Mo/SiO2,Rh-Mo/SiO2和Pt-Mo/SiO2都表现出高活性.
- 选择性催化Pd-Mo/SiO2的第三级酒精脱氧.
- XAS证实了金属M状态和在反应过程中发生变化的不同Mo氧化状态 (0,IV,VI);观察到Rh,Pd,Ir,Pt的合金形成 (M-Mo).
结论:
- 基于Mo的双金属催化剂在酒精HDO中显示出显著的结构-活性关系.
- 在纳米粒子表面上存在金属Mo物种对于初级/二级酒精激活至关重要.
- 三级酒精脱氧可能是通过脱水-化过程进行的,其机制取决于基质.
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