Journal ArticleElucidation of Ce/Zr ratio effects on the physical properties and catalytic performance of CuOx/CeyZr1−yO2 catalystsSifat, Mohammed [Materials Science and Chemical Engineering Department, Stony Brook University, Stony Brook, NY, 11794, USA]; Luchowski, Michal [Materials Science and Chemical Engineering Department, Stony Brook University, Stony Brook, NY, 11794, USA]; Pophali, Amol [Materials Science and Chemical Engineering Department, Stony Brook University, Stony Brook, NY, 11794, USA] (ORCID:0009000828786574); Jiang, Wenhui [Materials Science and Chemical Engineering Department, Stony Brook University, Stony Brook, NY, 11794, USA]; Lu, Yunfan [Materials Science and Chemical Engineering Department, Stony Brook University, Stony Brook, NY, 11794, USA]; Kim, Byeongseok [Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials, Inha University, Incheon, 22212, South Korea]; Kwon, Gihan [National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA] (ORCID:0000000279632136); Yoon, Kwangsuk [Department of Earth Resources and Environmental Engineering, Hanyang University, Seoul 04763, Republic of Korea]; Kim, Jihun [School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea]; An, Kwangjin [School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea] (ORCID:0000000252390296); Shim, Sang Eun [Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials, Inha University, Incheon, 22212, South Korea] (ORCID:0000000236786856); Song, Hocheol [Department of Earth Resources and Environmental Engineering, Hanyang University, Seoul 04763, Republic of Korea]; Kim, Taejin [Materials Science and Chemical Engineering Department, Stony Brook University, Stony Brook, NY, 11794, USA] (ORCID:000000020096303X)Although cerium oxide (CeO2) is widely used as a catalyst support, its limited defect sites and surface oxygen vacancy/mobility should be improved. The incorporation of zirconium (Zr) in the cerium (Ce) lattice is shown to increase the number of oxygen vacancies and improve catalytic activity. Using a fixed surface density (SD) of copper (∼2.3 Cu atoms per nm2) as a surface species, the role of the support (CeyZr1−yO2 (y = 1.0, 0.9, 0.6, 0.5, and 0.0)) and defect site effects in the CO oxidation reaction was investigated. Spectroscopic (e.g., Raman, XRD, XPS) and microscopic (e.g., SEM-EDX, HR-TEM) characterization techniques were applied to evaluate the defect sites, crystallite size, lattice parameters, chemical composition, oxidation states of elements and microstructure of the catalysts. The CO oxidation reaction with varied CO:O2 ratios (1 : 5, 1 : 1, and 1 :0.5 (stoichiometric)) was used as a model reaction to describe the relationship between the structure and the catalytic performance of each catalyst. Based on the characterization results of CeyZr1−yO2 materials, the addition of Zr causes physical and chemical changes to the overall material. The inclusion of Zr into the structure of CeO2 decreased the overall lattice parameter of the catalyst and increased the number of defect sites. The prepared catalysts were able to reach complete CO conversion (∼100%) at low temperature conditions (<200 °C), each showing varied reaction activity. The difference in CO oxidation activity was then analyzed and related to the structure, wherein Cu loading, surface oxygen vacancies, reduction–oxidation ability, CuOx–support interaction and oxygen mobility in the catalyst were the crucial descriptors.Royal Society of Chemistry2024-10-2810655967Catalysis Science & Technology14247107-71232044-4753https://doi.org/10.1039/D4CY01012D2050824National Science Foundation