Cerium based shells with palladium cores encapsulated: an efficient catalyst for carbon monoxide oxidation

Pd@Zr/CeO2 core-shell catalyst prepared by hydrothermal method was applied in CO oxidation reaction, exhibiting high CO oxidation activity at low temperature. XRD (X-ray diffraction) analysis demonstrated that the remarkable enhancement of catalytic performance was found to depend on the presence of more oxygen vacancies in the core-shell structure, which contributed higher content of and ready release of active oxygen species at low temperature, confirmed by H2-TPR (temperature programed reduction) results. Interestingly, introducing a small amount of zirconium (0.5 wt.%) exhibited a significant improvement of catalytic activity because the introduction of Zr further improved the amount of crystal defects and promoted the migration of oxygen species. Catalytic activity of different catalysts over CO oxidation reaction