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

Insufficient synergy between hydrolysis and hydrogenation seriously hinders the efficient conversion of insoluble cellulose in biomass utilization. Herein, using tobacco straw-derived lignin to prepare ordered mesoporous carbon (OMC), we report a complex-mediated strategy for constructing a Ni–P–O@Ni x P/OMC catalyst with tailored P–C–O doped sites and Ni δ+ –P–O δ− frustrated Lewis pairs (FLPs). Characterizations and DFT results indicate that the P–C–O sites in a P/O-doped OMC support promote H 2 O adsorption and polarization, accelerating H 3 O + generation for enhanced cellulose hydrolysis. Simultaneously, the Ni δ+ –P–O δ− FLPs on the Ni x P surface promote H 2 heterolysis and H 2 O dissociation, generating highly active H δ+ /H δ – and H 3 O + species that synergistically enhance hydrolysis and hydrogenation. Benefiting from the spatial coupling of hydrolysis and hydrogenation at the atomic scale, the prepared catalyst achieves an 80% sorbitol yield from cellulose in water at a low Ni loading of 4.5 wt %, along with satisfactory cycling stability. Increasing the Ni content to 8.0 wt % further raises the sorbitol yield to 89.5%, outperforming most reported noble-metal-based catalysts. Finally, a sorbitol yield in excess of 90% is obtained by using the residue after lignin extraction as the substrate. This work establishes a design paradigm for efficient cascade biomass conversion by creating atomic-scale P–C–O sites and Ni δ+ –P–O δ− FLPs that enable spatially coupled hydrolysis and hydrogenation through tailored electronic structures.