Highly Exposed Subnanometric Palladium Ensembles on Yttrium Oxide Enable Boosted Catalytic Performance for Heck...

Area of Science:

• Heterogeneous catalysis
• Organic synthesis
• Materials science

Background:

• Developing efficient catalysts for Heck cross-coupling is crucial for C-C bond formation.
• Single atom catalysts (SACs) face limitations due to insufficient metallic properties for complex transformations.

Purpose of the Study:

• To design and synthesize a novel heterogeneous catalyst overcoming SAC limitations for Heck coupling.
• To achieve high catalytic performance, selectivity, and stability in C-C coupling reactions.

Main Methods:

• Synthesis of palladium ensembles on oxygen vacancy-rich yttrium oxide (Pd_C/Y₂O_3-x).
• Catalytic testing of the Heck cross-coupling reaction between iodobenzene and methyl acrylate.
• Characterization using spectroscopic methods and theoretical calculations.

Main Results:

• Achieved 99% selectivity and conversion for methyl cinnamate synthesis within 3 hours under mild conditions.
• Demonstrated catalyst recyclability, scalability, and effectiveness with aryl bromides.
• Identified the crucial role of palladium cluster structure and metal-support interactions.

Conclusions:

• The Pd_C/Y₂O_3-x catalyst exhibits superior performance for Heck coupling, surpassing SAC limitations.
• This work establishes a universal design principle for single-cluster catalysts in organic transformations.
• Highlights the significance of geometric and electronic structures for catalyst activity and stability.