Temperature‐Regulated N‐Involved Ru Nucleation on Lignin‐Derived Carbon for Enhanced Catalytic Transfer Hydrogenation of Levulinic Acid to γ‐Valerolactone

Sustainably sourced lignin presents great potential as carbon‐based metal catalyst supports owing to its high carbon content as well as the ability to coordinate with metal ions. However, the rational regulation of the lignin‐supported metal catalyst fabrication process to optimize their morphology and activity remains a challenge. Herein, we proposed a straightforward strategy to regulate the N content and species in the supports, thereby governing the nucleation behavior of Ru nanoparticles by varying the sintering temperature, for targeted enhancement of the catalytic performance of lignin‐supported Ru‐based catalysts. The sintering temperature of 700 °C was conducive to reducing the escape of elemental N and maintaining a high percentage of pyridinic‐N species, which was beneficial to the adsorption and immobilization of Ru by the supports, resulting in the formation of Ru nanoparticles with a small size (1.93 nm). In the catalytic transfer hydrogenation (CTH) of levulinic acid (LA) to γ‐valerolactone (GVL) using isopropanol as the hydrogen donor, the obtained catalyst demonstrated nearly 100% LA conversion and GVL selectivity under mild conditions (120 °C) with good reusability. This strategy achieves directional control over the structure of lignin‐supported metal catalysts through a simple method, providing guidance for the efficient synthesis of these catalysts.