(2026) Applied Catalysis A: General_Influence of thermal treatment on structure and catalytic performance of ceria-zirconia supported copper oxide (CuO_x/Ce_yZr_1-yO₂) catalysts for CO oxidation

Luchowski M.; Pophali A.; Kwon G.; Park J.; Kwon E.E.; Halada G.; Kim T.

(Elsevier B.V.) Applied Catalysis A: General ISSN: 0926860X Vol.718 Issue. Article No.120911 DOI: 10.1016/j.apcata.2026.120911

Copper oxide (CuO_x) supported on ceria-zirconia (Ce_yZr_1-yO₂, y = 1.0, 0.5, 0.0) catalysts were investigated to elucidate the effects of thermal treatment on their physicochemical properties and catalytic performance in carbon monoxide (CO) oxidation. The catalysts were synthesized via a one-pot chemical vapor deposition (OP-CVD) method at 700˚C and 900˚C with controlled Cu loading. Characterization techniques, including synchrotron X-ray diffraction (S-XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma spectroscopy (ICP), and N2 adsorption-desorption, were implemented to probe the crystalline structure, molecular and electronic structure, oxygen vacancies, specific surface area (SSA) and metal loading. CO oxidation was chosen as a model reaction to explore the structure-catalytic performance relationship. A ∼100% CO conversion was achieved at < 150˚C, particularly with the CuO_x/CeO₂ catalyst calcined at 700˚C. In contrast, calcination at 900˚C caused a ∼90% decrease in SSA and a ∼24% increase in T₅₀. Activity tests revealed that increasing ZrO₂ content lowered CO oxidation activity despite generating more defect sites. In-situ measurement of the 700 °C calcined samples revealed the presence of stable and unstable defects in CuO_x/Ce_0.5Zr_0.5O₂ and CeO₂ respectively, which play a key role in the activity of the catalysts. The results highlight that catalytic performance is closely related to the SSA. Furthermore, an optimum calcination temperature favor significant oxygen vacancy formation with required CuO_x-support interactions, enhancing redox properties and catalytic performance. © 2026 Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

The authors acknowledge funding support from the National Science Foundation (NSF-CBET-2050824). The authors would also like to acknowledge the Advanced Energy Research and Technology Center (AERTC) for the facilities at Stony Brook University. This research used the 28-ID-1 beamline of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704.