Uniform and Porous Ce_1–xZn_xO_2−δ Solid Solution Nanodisks: Preparation and Their CO Oxidation Activity

With increasing interest in new catalytic materials based on doping of ceria with lower-valence metal cation, in this paper, a series of Ce_1–xZn_xO_2‑δ (Ce–Zn_x) solid solution catalysts were prepared by a surfactant-free coprecipitation method. The catalytic activity of ceria nanostructures was enhanced by increasing density of oxygen vacancy defects in these catalysts by doping. The morphology of the nanodisks can be facilely controlled by changing reaction parameters such as dosage of reagent, reaction time, and temperature. In addition, Ce–Zn_x catalyst supported with Au nanoparticles was also prepared, and its activity for CO oxidation was greatly enhanced, due to the acceleration of gas-phase oxygen activation and transferring via spillover. It turns out that the synthesized Ce–Zn_x materials supported with Au nanoparticles exhibit excellent activity for removing CO by catalytic oxidation with a 100% conversion at 85 °C, demonstrating promising applications in environmental remediation.