Designing catalysts with precisely balanced acid-metal bifunctional sites is a central challenge in the selective conversion of biomass. In this work, we report a bifunctional Ru1.5/Fe36–SiO2 catalyst developed through a simple and scalable two-step synthesis involving coprecipitation and impregnation. This catalyst demonstrated exceptional performance in the selective C–C and C–O bond cleavage of sucrose, with near-complete conversion (>99%) and a high total carbon yield of 82.2% to diols and lower alcohols. Notably, the carbon yield of the main product, 1,2-propanediol, reached 52.5%, surpassing the performance of most previously reported Ru-based catalysts. Characterization revealed that the catalyst with an optimal Fe content of 36 wt % possessed a high specific surface area (249.66 m2/g). This composition created an acidic environment enriched with weak to medium-strength acids, predominantly of the Lewis type. More importantly, it induced the formation of abundant Ru–Fe2O3 interfaces. At this interface, charge transfer generates Ru0 sites with optimal electron density, which synergize with the predominantly Lewis acid sites of weak to moderate strength. This synergy not only promotes retro-aldol condensation and selective hydrogenolysis but also suppresses side reactions like deep dehydration and excessive C–C bond cleavage. The catalyst exhibited excellent stability, retaining over 94% of its initial activity after four consecutive cycles. Furthermore, its activity could be fully restored through a simple reduction treatment, highlighting its strong potential for industrial applications. This work offers a valuable strategy for tuning metal-acid synergy to design highly efficient supported catalysts for complex reaction networks.
Luo et al. (Mon,) studied this question.