Efficient Alkene Hydroformylation by Co-C Symmetry-Breaking Sites

Area of Science:

• Heterogeneous catalysis
• Materials science
• Chemical engineering

Background:

• Alkene hydroformylation is a major industrial process.
• Non-noble heterogeneous catalysts often suffer from low activity and stability.
• Developing efficient and stable catalysts is crucial for industrial applications.

Purpose of the Study:

• To design and synthesize a novel non-noble heterogeneous catalyst for alkene hydroformylation.
• To investigate the structure-activity relationship of the catalyst.
• To enhance the catalytic performance in terms of activity and stability.

Main Methods:

• Synthesis of a 1% Co2C/SiO2 catalyst with specific Co-C-vacancy-Co-C symmetry-breaking sites.
• Characterization of the catalyst's surface polarity and charge density gradient.
• Evaluation of reactant adsorption, activation, and intermediate polarity.
• Measurement of catalytic activity and stability for propene hydroformylation.

Main Results:

• The Co2C/SiO2 catalyst exhibited a polar surface with a moderate charge density gradient at Co atoms.
• Enhanced adsorption and activation of reactants, and increased polarity between intermediates were observed.
• Reduced spatial distance between adsorption sites effectively lowered the reaction energy barrier.
• A turnover number of 18,363 for propene hydroformylation was achieved, orders of magnitude higher than existing Co-based catalysts.
• The catalyst demonstrated high stability during the reaction.

Conclusions:

• The constructed catalyst with symmetry-breaking sites significantly boosts alkene hydroformylation efficiency.
• The methodology provides a new approach for designing highly active and stable atomically engineered catalysts.
• This work holds great potential for advancing industrial catalytic processes.