Efficient epimerization of highly concentrated glucose to mannose over electronic structure-modulated Mo/NC catalyst

Area of Science:

• Catalysis
• Materials Science
• Biochemistry

Background:

• Mannose has significant therapeutic applications.
• Efficient catalytic conversion of concentrated glucose to mannose is challenging due to low catalytic efficiency.

Purpose of the Study:

• To develop a highly efficient and stable catalyst for the epimerization of concentrated glucose to mannose.
• To investigate the catalytic mechanism and the role of electronic metal-support interactions.

Main Methods:

• Synthesis of a Mo/NC-300 catalyst using pyrolysis.
• Catalytic testing for glucose epimerization under high concentration (50 wt%).
• Characterization techniques and density functional theory (DFT) calculations.
• Isotope labeling experiments to elucidate the reaction mechanism.

Main Results:

• The Mo/NC-300 catalyst achieved 33.4% yield and 94.6% selectivity for mannose from concentrated glucose.
• High catalytic productivity of 123.7 mmol·g_cat^-1·h^-1 was observed.
• DFT calculations indicated modulated electronic structure of Mo species enhancing glucose adsorption and lowering the epimerization barrier.
• The catalyst demonstrated excellent stability and reusability, attributed to the hydrophobic nitrogen-doped carbon (NC) layer.

Conclusions:

• The developed Mo/NC-300 catalyst effectively overcomes challenges in concentrated glucose epimerization, offering high efficiency, stability, and reusability.
• The study provides insights into electronic metal-support interactions influencing catalytic performance.
• The catalyst's stability is enhanced by the hydrophobic NC support, facilitating practical applications.