Pd-Ceria/CNMs Composites as Catalysts for CO and CH₄ Oxidation

Area of Science:

• Materials Science
• Catalysis
• Environmental Science

Background:

• Composite materials offer a promising avenue for air purification through catalytic oxidation of toxic compounds.
• Carbon nanomaterials (CNMs) provide a versatile support for catalytic components due to their unique structural and electronic properties.

Purpose of the Study:

• To investigate palladium and ceria composites supported on various carbon nanomaterials for CO and CH4 oxidation.
• To understand the role of CNM defect structure and morphology in stabilizing catalytic species and influencing activity.

Main Methods:

• Synthesis of palladium and ceria composites on multiwall carbon nanotubes, carbon nanofibers, and Sibunit.
• Characterization using instrumental methods to analyze the state and dispersion of catalytic components.
• Evaluation of catalytic performance in CO and CH4 oxidation reactions.

Main Results:

• Defective sites on CNMs stabilize highly dispersed PdO and CeO2 nanoparticles, amorphous clusters, and single atoms.
• Reactant activation occurs on palladium species, utilizing oxygen from the ceria lattice.
• Interactions between PdO and CeO2 influence oxygen transfer and catalytic activity.
• CNM morphology and defect structure dictate particle size and stabilization of components.

Conclusions:

• The synergistic effect between palladium and ceria, stabilized by CNM defects, leads to highly effective catalytic oxidation.
• CNM-supported palladium-ceria catalysts demonstrate significant potential for air purification applications.
• Optimized dispersion of active species on carbon nanotubes results in superior performance for both CO and CH4 oxidation.