Interfacial Engineering of Frustrated Lewis Pairs for Promoting Cellulose-to-Sorbitol Cascade Conversion

Area of Science:

• Catalysis
• Biomass Conversion
• Materials Science

Background:

• Inefficient synergy between hydrolysis and hydrogenation limits cellulose conversion in biomass utilization.
• Developing catalysts with enhanced activity and selectivity is crucial for sustainable biomass valorization.

Purpose of the Study:

• To design and synthesize a novel catalyst for efficient cellulose conversion into sorbitol.
• To investigate the synergistic effects of hydrolysis and hydrogenation facilitated by tailored catalyst active sites.

Main Methods:

• Preparation of ordered mesoporous carbon (OMC) from tobacco straw-derived lignin.
• Construction of a Ni-P-O@NiₓP/OMC catalyst featuring P-C-O doped sites and Ni^δ+-P-O^δ- frustrated Lewis pairs (FLPs).
• Characterization techniques and Density Functional Theory (DFT) calculations to elucidate catalytic mechanisms.

Main Results:

• The P-C-O sites promoted cellulose hydrolysis by enhancing H₂O adsorption and polarization.
• Ni^δ+-P-O^δ- FLPs facilitated H₂ heterolysis and H₂O dissociation, generating active species for hydrogenation.
• A catalyst with 4.5 wt% Ni loading achieved an 80% sorbitol yield, increasing to 89.5% with 8.0 wt% Ni.
• Sorbitol yields exceeding 90% were achieved using lignin-extracted residue as substrate.

Conclusions:

• The developed catalyst enables efficient, spatially coupled hydrolysis and hydrogenation at the atomic scale.
• This strategy offers a new paradigm for designing catalysts for cascade biomass conversion.
• The catalyst demonstrates high performance and stability, outperforming many noble-metal-based catalysts.