Low-temperature CO oxidation over Cu/Pt co-doped ZrO₂ nanoparticles synthesized by solution combustion

Area of Science:

• Materials Science
• Catalysis
• Nanotechnology

Background:

• Zirconium dioxide (ZrO2) is a widely studied material for catalytic applications.
• Carbon monoxide (CO) oxidation is a critical reaction in environmental catalysis and industrial processes.
• Developing highly active and stable catalysts is essential for efficient CO oxidation.

Purpose of the Study:

• To synthesize and characterize copper (Cu) and platinum (Pt) co-doped ZrO2 nanoparticles.
• To evaluate the catalytic performance of these nanomaterials for CO oxidation.
• To investigate the role of doping and oxygen vacancies in enhancing catalytic activity and stability.

Main Methods:

• Solution combustion synthesis was employed to prepare Cu/Pt co-doped ZrO2 nanoparticles.
• High-resolution transmission electron microscopy (HRTEM) was used to determine nanoparticle size.
• X-ray diffraction (XRD) and Raman spectroscopy were utilized to confirm crystal structure and oxygen vacancies.

Main Results:

• Cu/Pt co-doped ZrO2 nanoparticles with a size of approximately 10 nm were successfully synthesized.
• The co-doped nanoparticles exhibited a cubic structure with significantly increased oxygen vacancies.
• A remarkable 175 °C reduction in the CO conversion temperature (T50) was observed compared to bare ZrO2.
• The catalyst demonstrated excellent stability, maintaining activity for approximately 70 hours.
• The apparent activation energy for CO oxidation was determined to be 45.6 kJ·mol-1.

Conclusions:

• Cu/Pt co-doping effectively enhances the catalytic activity and stability of ZrO2 for CO oxidation.
• The improved performance is attributed to smaller particle size, increased oxygen vacancies, high surface area, and thermal stability.
• The developed nanomaterials show great promise for applications in CO oxidation catalysis.