Enhancing CO Preferential Oxidation in H₂-Rich Stream on Solid Solution CuO_CeO₂ Catalyst with Abundant Oxygen...

Area of Science:

• Catalysis
• Materials Science
• Chemical Engineering

Background:

• CO preferential oxidation is crucial for fuel cell applications.
• Developing efficient non-noble metal catalysts remains a challenge.
• Metal-Organic Frameworks (MOFs) offer unique structural advantages for catalyst design.

Purpose of the Study:

• To prepare solid solution CuO-CeO2 catalysts derived from Ce-based MOFs.
• To investigate the catalyst's performance in CO preferential oxidation.
• To elucidate the reaction mechanism using DFT calculations.

Main Methods:

• Synthesis of CuO-CeO2 catalysts using Ce-based MOFs as precursors.
• Characterization of catalyst structure and dispersion.
• Testing catalytic performance for CO preferential oxidation.
• Density Functional Theory (DFT) calculations for mechanism study.

Main Results:

• Achieved 99.5% CO conversion and 58.2% CO2 selectivity at high WHSV.
• Demonstrated excellent stability over 150 hours with no efficiency loss.
• Identified highly dispersed Cu species, some atomically embedded in CeO2 lattice.
• DFT revealed favorable O2 adsorption at Cu-Ce-V[O] sites and CO adsorption at Cu sites.

Conclusions:

• MOF-derived CuO-CeO2 catalysts are highly effective for CO preferential oxidation.
• High dispersion of Cu species and oxygen vacancies are key to catalytic activity.
• The noncompetitive Langmuir-Hinshelwood mechanism is favored.
• This strategy provides insights for designing efficient non-noble metal catalysts.