Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, Shanghai 200438, China.
Wolfson Catalysis Centre, Department of Chemistry, University of Oxford, Oxford OX1 3QR, UK.
Molecules. 2019 Feb 1;24(3):526. doi: 10.3390/molecules24030526.
Three morphology-controlled CeO₂, namely nanorods (NRs), nanocubes (NCs), and nanopolyhedra (NPs), with different mainly exposed crystal facets of (110), (100), and (111), respectively, have been used as supports to prepare Ru (3 wt.%) nanoparticle-loaded catalysts. The catalysts were characterized by H₂-temperature programmed reduction (H₂-TPR), CO⁻ temperature programmed desorption (CO-TPD), N₂ adsorption⁻desorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM) and energy-dispersive X-ray spectroscopy (XDS). The characterization results showed that CeO₂-NRs, CeO₂-NCs, and CeO₂-NPs mainly expose (110), (100) and (111) facets, respectively. Moreover, CeO₂-NRs and CeO₂-NCs present higher oxygen vacancy concentration than CeO₂-NPs. In the CO₂ reforming of methane reaction, Ru/CeO₂-NR and Ru/CeO₂-NC catalysts showed better catalytic performance than Ru/CeO₂-NPs, indicating that the catalysts with high oxygen vacancy concentration are beneficial for promoting catalytic activity.
三种形貌可控的 CeO₂，即纳米棒（NRs）、纳米立方体（NCs）和纳米多面体（NPs），分别具有不同的主要暴露晶面（110）、（100）和（111）。这些 CeO₂被用作负载 Ru（3wt.%）纳米颗粒催化剂的载体。采用 H₂-程序升温还原（H₂-TPR）、CO⁻程序升温脱附（CO-TPD）、N₂吸附-脱附、X 射线衍射（XRD）、拉曼光谱、X 射线光电子能谱（XPS）、透射电子显微镜（TEM）和高分辨率透射电子显微镜（HRTEM）和能量色散 X 射线能谱（EDS）对催化剂进行了表征。表征结果表明，CeO₂-NRs、CeO₂-NCs 和 CeO₂-NPs 分别主要暴露（110）、（100）和（111）晶面。此外，CeO₂-NRs 和 CeO₂-NCs 具有比 CeO₂-NPs 更高的氧空位浓度。在甲烷二氧化碳重整反应中，Ru/CeO₂-NR 和 Ru/CeO₂-NC 催化剂表现出比 Ru/CeO₂-NPs 更好的催化性能，表明具有高氧空位浓度的催化剂有利于提高催化活性。
