Oxygen Vacancy-Induced Interfacial Lanthanum Hydride and Hydroxide Bifunctional Sites for Selective Hydrogenolysis of Furanic Compounds to Alkyl Diols

Selective hydrogenolysis of C–O bonds in biomass-derived oxygenated molecules is of great significance for the conversion of biomass to chemicals and fuels, especially for the inert C–O–C bonds in tetrahydrofuran rings. However, the lack of precise active sites results in the low activity of this reaction. In this work, the metal–support interfacial structure of the Ni–La₂O₃ catalyst was well-controlled by reducing LaNiO₃ perovskite at different temperatures. During the reduction, the exsolution and segregation of Ni in the LaNiO3 perovskite led to the formation of metallic Ni nanoparticles and interfacial oxygen-vacant Ni²⁺-O_v-La³⁺ sites. Hydrogen spillover from Ni nanoparticles to the interface promoted the in situ generation of La–OH species under reaction conditions. At the same time, the oxygen vacancies at the interfacial Ni²⁺-O_v-La³⁺ sites can accommodate the spilled H, inducing the formation of the La–H species. The hydroxyl group in tetrahydrofurfuryl alcohol (THFA) interacted with La–OH through a metal alkoxide intermediate, which was subsequently hydrogenolyzed by the La–H to produce 1,5-pentanediol (1,5-PeD). The intimate La–H and La–OH bifunctional sites on the metal–support interface have a strong synergistic effect, endowing the Ni–La₂O₃ catalyst with a high THFA hydrogenolysis activity. The proposed interfacial La–H assisted C–O bond hydrogenolysis provides an idea for the design of efficient hydrodeoxygenation catalysts for biomass upgrading.

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