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Bifunctional hydrogenation and acid catalysis in aqueous solvents over reduced metal-supported solid acids is a common method for tandem reactions of biomass derivates. Traditionally, hydrogen (H 2 ) was used as the reductant for the hydrogenation steps and rarely reported as a promoter in the acid-catalyzed steps. Herein, Co-embedded N-doped carbon (Co@Co-NCs) is used for the bifunctional catalytic conversion of furfurals into cyclopentanols. In addition to being a reductant for the hydrogenation step over the Co nanoparticle core, H 2 can act as a catalyst to induce the acid−base transformation of the Co-NC shell from Lewis acid−base pairs into Brønsted acid−base pairs via heterolysis and a subsequent water-mediated mechanism, which largely promotes the acidcatalyzed step.

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Catalytic hydrogenolysis of biobased furan aldehydes (i. e., 5methylfurfural, 5-hydroxymethylfurfural) to 2,5-dimethylfuran has gained extensive interest for biomass-derived fuels and chemicals. Herein, a class of NiCo 2 O 4 -supported palladium with considerable oxygen defects was synthesized by hydrogen plasma etching and phosphating methods. The oxygen defects not only promoted the hydrogenation of the C=O group but also enhanced the accessibility of coordinatively unsaturated metal cations with Lewis acidity for the hydrogenolysis of the CÀ OH group. Meanwhile, the additional Brønsted acidity in Pd/ NiCo 2 O 4-x obtained by phosphating could further strengthen the hydrogenolysis ability by the etherification route of CÀ OH. Finally, Pd/NiCo 2 O 4-x exhibited the most effective performance with 2,5-dimethylfuran yields of 92.9 and 90.5 % from 5-methylfurfural and 5-hydroxymethylfurfural, respectively. These catalytic mechanisms were confirmed by in-situ infrared spectroscopy and control experiments. Furthermore, the catalyst showed outstanding recycling stability. This work shows powerful synergistic catalysis in the hydrogenolysis reaction by multifunctional active sites.

The hydrogenative ring‐opening of furfurals (furfural and 5‐methylfurfural) to linear diols (1,4‐pentanediol and 2,5‐hexanediol) is of great significance for bioderived fine chemical synthesis. Unfortunately, the catalytic activity and selectivity are unsatisfactory because of the interference of various side reactions, such as overhydrogenation to tetrahydrofurans. Herein, the preparation of an iodine (I) modified Pt‐based catalyst with abundant Pt‐I pairs is reported for the first time and shows high catalytic efficiency for linear diol synthesis with a yield of 80%–90% via the hydrogenative ring‐opening route, whereas bare Pt counterpart only shows tetrahydrofuran synthesis via the overhydrogenation route. The catalytic reaction mechanism shows the in‐situ hydrogen spillover‐promoted H−‐Pt‐I‐H+ pairs not only supply hydrogenation sites for the C=O hydrogenation step but also provide Brønsted acidic sites for the ring‐opening step. This work presents a feasible and convenient strategy for bifunctional catalysis with powerful linear diol synthesis over iodine‐modified noble metals.