在SO2诱导硫化过程中Pd/CeO2的结构转化和氧化还原化学:一个XAFS实地研究
Saki Shigenobu1, Takeharu Sugiyama2, Hajime Hojo3
1Department of Molecular and Material Sciences, Graduate School of Engineering Sciences, Kyushu University, 6-1, Kasugakoen, Kasuga, Fukuoka 816-8580, Japan.
Dalton transactions (Cambridge, England : 2003)
|March 6, 2026
概括
在氧化 (CeO2) 催化剂上的 (Pd) 将硫化从表面反应转变为散装工艺. 这种Pd推广增强了硫酸氧化物的稳定性,这对于催化应用至关重要.
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:
- 氧化 (CeO2) 是催化中的关键材料,但其硫化行为尚未完全理解.
- 了解硫化过程中的结构演变对于设计稳定的催化剂至关重要.
研究的目的:
- 为了阐明在SO2诱导硫化过程中Pd/CeO2催化剂的结构变化.
- 为了比较赤裸的CeO2与Pd促进的CeO2的硫化机制.
- 为了研究在硫化过程中的作用.
主要方法:
- 在现场的X射线吸收细结构 (XAFS) 光谱.
- 在Ce L3边缘和Pd L3边缘进行X射线吸收近边缘结构 (XANES) 分析.
- 硫K边缘分析.硫K边缘分析.
主要成果:
- 在硫化过程中,Pd/CeO2表现出大量的氧气参与,与裸体CeO2.2的表面限制硫化不同.
- 留在氧化状态,防止PdS的形成.
- 硫仅形成硫酸盐 (SO4^2-),没有中间物种.
- 在Pd/CeO2上形成的硫酸氧化物 (Ce2O2SO4) 显示出对再氧化的增强稳定性.
结论:
- 作为促进剂,增强CeO2网格内的氧气流动性.
- 硫化从一个表面限制的过程转变为一个大量可访问的过程,Pd.
- 在Pd/CeO2催化剂中,硫酸氧化物阶段的稳定性得到了改善.
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