A Sol–Gel Strategy-Constructed Co/La ₂ O ₃ Catalyst for Highly Efficient Furfural Hydrogenation to 1,5-Pentanediol: Role of LaH _<i>x</i>

The selective catalytic hydrogenation of furfural to 1,5-pentanediol (1,5-PeD) is a transformation of important scientific significance. This process proceeds through the initial hydrogenation of furfural to tetrahydrofurfuryl alcohol (THFA), followed by selective cleavage of the C–O bond at the C 2 position mediated by active sites on the catalyst surface. However, precise control of C–O bond cleavage remains a major challenge, often resulting in undesired byproducts such as 1,2-pentanediol (1,2-PeD). Herein, a Co 4 /La 2 O 3 -CA-850 catalyst rich in oxygen vacancies (Ov) and LaH x species was synthesized via a citric acid (CA) sol–gel method. After high-temperature reduction with H 2, a well-defined interfacial structure of Co–La 2 O 3 emerged, and it played a critical role in the catalytic process. This interface effectively adsorbed oxygen atoms from THFA and enabled selective activation of the C 2 site through hydrogen species (H – ) derived from LaH x, facilitating highly efficient C 2 –O 2 bond cleavage. Mechanistic study also clearly demonstrated the reaction pathway. Finally, the catalytic system realized a 64.9% yield of 1,5-PeD. These findings underscore the potential application of Co/La 2 O 3 -based catalysts for biomass upgrading and establish a sustainable, environmentally benign route for 1,5-PeD preparation.