Prabhu M K, Groot I M N
Gorlaeus Laboratories, Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands.
Phys Chem Chem Phys. 2021 Apr 14;23(14):8403-8412. doi: 10.1039/d0cp03481a. Epub 2021 Mar 25.
Here we present the results of a study carried out to investigate the simultaneous sulfidation of Co and Mo oxide nanoparticles on Au(111) as a synthesis strategy to prepare a model catalyst for hydrodesulfurization (HDS). We make use of scanning tunneling microscopy and X-ray photoelectron spectroscopy to track the changes in morphology and chemistry during the synthesis of a mixed Mo and Co oxide precursor and the sulfidation thereafter, to the respective sulfides. We investigated the effects of temperature and the duration of sulfidation on the completeness of the sulfidation process. Our study shows that the formation of MoS with the CoMoS edge (the desired model catalyst) is not affected by the time or the temperature of sulfidation. However, the yield of the Co-promoted MoS slabs is limited by the formation of large clusters due to the spreading of Mo and Co oxide phases upon sulfidation. Complete sulfidation of the mixed oxide precursor to Co-promoted MoS can be accelerated by increasing the sulfidation temperature to 730 K due to the thermally activated nature of Mo oxide sulfidation. Thus, we demonstrate that using a mixed Mo and Co oxide precursor as a starting point for the Co-promoted MoS phase for fundamental catalytic studies is a viable strategy.
在此，我们展示了一项研究的结果，该研究旨在探究金（111）上钴和钼氧化物纳米颗粒的同步硫化，以此作为一种合成策略来制备用于加氢脱硫（HDS）的模型催化剂。我们利用扫描隧道显微镜和X射线光电子能谱来追踪在混合钼和钴氧化物前驱体合成过程中以及随后硫化至各自硫化物过程中的形态和化学变化。我们研究了温度和硫化持续时间对硫化过程完整性的影响。我们的研究表明，具有CoMoS边缘的MoS（所需的模型催化剂）的形成不受硫化时间或温度的影响。然而，由于硫化时钼和钴氧化物相的扩散形成大簇，钴促进的MoS片层的产率受到限制。由于钼氧化物硫化的热活化性质，将硫化温度提高到730 K可加速混合氧化物前驱体完全硫化成钴促进的MoS。因此，我们证明，使用混合钼和钴氧化物前驱体作为钴促进的MoS相用于基础催化研究的起点是一种可行的策略。
