KAUST Catalysis Center and Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia.
KAUST Catalysis Center and Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia.
J Colloid Interface Sci. 2022 Apr;611:739-751. doi: 10.1016/j.jcis.2021.11.172. Epub 2021 Nov 30.
A dendritic PdCu/CeZrO (PdCu/CZ-3) catalyst with uniform spherical morphology was prepared for boosting the catalytic performance of CO hydrogenation to methanol (MeOH). The open dendritic pore channels and small particle sizes could reduce not only the diffuse resistance of reactants and products but also increase the accessibility between the active sites (PdCu and oxygen vacancy) and the reactants (H and CO). More spillover hydrogen could be generated due to the highly dispersed PdCu active metals over the PdCu/CZ-3 catalyst. PdCu/CZ-3 can stimulate the generation of more Ce cations, which is beneficial to produce more oxygen vacancies on the surface of the CZ-3 composite. Spillover hydrogen and oxygen vacancy could promote the formate and methoxy routes over PdCu/CZ-3, the primary intermediates producing MeOH. PdCu/CZ-3 displayed the highest CO conversions (25.5 %), highest MeOH yield (6.4 %), highest PdCu-TOF (7.7 h) and superior 100 h long-term stability than those of other PdCu/CeZrO analogs and the reference PdCu/CeO and PdCu/ZrO catalysts. Density functional theory (DFT) calculations and in situ DRIFTS were performed to investigate the CO - MeOH hydrogenation mechanism.
一种具有均匀球形形貌的树枝状 PdCu/CeZrO（PdCu/CZ-3）催化剂被制备用于提高 CO 加氢制甲醇（MeOH）的催化性能。开放的树枝状孔道和较小的颗粒尺寸不仅可以降低反应物和产物的扩散阻力，还可以增加活性位（PdCu 和氧空位）与反应物（H 和 CO）之间的可及性。由于 PdCu 活性金属在 PdCu/CZ-3 催化剂上高度分散，因此可以产生更多的溢流氢。PdCu/CZ-3 可以刺激更多的 Ce 阳离子的产生，这有利于在 CZ-3 复合材料表面产生更多的氧空位。溢流氢和氧空位可以促进 PdCu/CZ-3 上的甲酸盐和甲氧基途径，这是生成 MeOH 的主要中间体。与其他 PdCu/CeZrO 类似物和参比 PdCu/CeO 和 PdCu/ZrO 催化剂相比，PdCu/CZ-3 表现出最高的 CO 转化率（25.5%）、最高的 MeOH 收率（6.4%）、最高的 PdCu-TOF（7.7 h）和优异的 100 小时长期稳定性。通过密度泛函理论（DFT）计算和原位 DRIFTS 研究了 CO-MeOH 加氢反应机理。
