Synergistic Solvent-Surface Interactions Enable Alkyne Semihydrogenation at Palladium

Area of Science:

• Catalysis
• Materials Science
• Organic Chemistry

Background:

• Heterogeneous catalysis is crucial for fine-chemical synthesis, but achieving high yield and selectivity remains challenging.
• Alkyne semihydrogenation is a key industrial process, yet controlling product selectivity is a significant hurdle.
• Current methods often rely on complex reactants or less favorable dopants.

Purpose of the Study:

• To develop a highly selective catalyst for alkyne semihydrogenation.
• To investigate the synergistic effects of catalyst design, reaction conditions, and solvent-surface interactions.
• To explore catalyst-solvent codesign as a sustainable alternative.

Main Methods:

• Fabrication of nickel (Ni) foam supports decorated with ultralow loading of palladium (Pd)/palladium oxide (PdO_x) nanoparticles on a carbonized polydopamine interface.
• Tuning catalyst performance with a thin layer of aluminum oxide (Al₂O₃).
• Combined computational and experimental studies to elucidate reaction mechanisms and solvent-surface interactions.

Main Results:

• Demonstrated highly selective alkyne semihydrogenation using the designed Ni-Pd/C-Al₂O₃ catalyst system.
• Achieved good functional group tolerance and applicability in flow reactor systems.
• Identified synergistic effects between solvent-surface interactions and palladium surface reduction crucial for selectivity.

Conclusions:

• The developed catalyst system offers a promising approach for selective alkyne semihydrogenation.
• Catalyst-solvent codesign presents a benign and efficient alternative for fine-chemical synthesis.
• This work paves the way for more sustainable catalytic processes.