Engineering CuOx–ZrO2–CeO2 nanocatalysts with abundant surface Cu species and oxygen vacancies toward high catalytic performance in CO oxidation and 4-nitrophenol reduction

Abstract

Highly dispersed surface Cu species and oxygen vacancies are important for CuO_x–CeO₂ catalysts in many reactions, but it is difficult to increase the concentrations of highly dispersed Cu species and oxygen vacancies simultaneously by only adding a Cu component. Herein, CuO_x–ZrO₂–CeO₂ (CZC) nanocatalysts with different ratios of Cu/Zr have been effectively produced by a simple solvent-free synthetic strategy. The effect of Zr doping on the structure and reactivity of the CuO_x–CeO₂ catalysts has been investigated with the help of carbon monoxide (CO) oxidation and 4-nitrophenol (4-NP) reduction as model reactions. It is revealed that the introduction of Zr relieved the agglomeration of surface Cu species, produced more oxygen vacancies in the interior and Cu⁺ species on the surface of the catalyst, and increased the reducibility of CuO_x–CeO₂. The CZC catalysts show remarkably enhanced catalytic activity due to the abundant surface active sites and the improved redox properties provided by the suitable doping of Zr into CuO_x–CeO₂. This work not only offers a practicable way to reconstruct the distribution of active metals on the metal oxide support but also provides a high-efficiency strategy to prepare oxide catalysts with excellent catalytic performance.