With the rapid development of transportation and vehicles, the elimination of NOx and CO has highly attracted public attention. In this work, vacancy-rich CeO2 nanopencil supported CuO catalysts (CuO/CeO2-NPC) were successfully prepared for NO reduction by CO. Importantly, CeO2 with nanopencil-like shape (CeO2-NPC) have been synthesis by solvothermal method for the first time. The physicochemical properties of all samples were studied in detail by combining the means of X-ray diffraction (XRD), Raman spectroscopy, electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), H2-temperature-programmed reduction (H2-TPR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), N2 physisorption (Brunauer-Emmett-Teller), and NO and CO temperature-programmed desorption (NO-TPD and CO-TPD) techniques. Compared with CeO2 nanorods and nanoparticles supported CuO catalysts (CuO/CeO2-NR and CuO/CeO2-NP), the CuO/CeO2-NPC catalysts showed the highest catalytic activity, affording more than 90% NO conversion at 69 °C as well as excellent H2O tolerance at 150 °C, which is superior to catalysts previously reported. Characterization results indicated that the synergistic effect between the well-dispersed CuO and the CeO2 nanopencil support enables a favorable electron transfer between these components and enhances the density of surface oxygen vacancies and Cu+ species, which consequently accelerating the redox cycle. The results indicated that the morphology control of CeO2 support could be an efficient way to evidently enhance the catalytic performance for NO + CO reaction.
Keywords: CuO/CeO2; NO reduction by CO; Nanopencils; Oxygen vacancies.
© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.