Constructing Ultrafine Ru Nanoclusters via a Dual‐Confinement Strategy: Synergizing Hierarchical Pores and Electronic Modulation for Efficient Lignin Hydrogenolysis

Abstract

Lignin hydrogenolysis is a promising route to separable aromatic monomers, yet practical upgrading is still hindered by macromolecular mass‐transfer limitations and the aggregation/deactivation of metal sites. Herein, we propose a “dual‐confinement” strategy to construct ultrafine Ru nanoclusters supported on lignin‐based N‐doped hierarchical porous carbon, utilizing lignin itself as the precursor. This architecture synergizes physical confinement via a potassium oxalate‐activated hierarchical pore network, with chemical confinement through in situ nitrogen doping that anchors Ru species. The resulting catalyst exhibits exceptional performance, achieving 99.8% conversion of model compounds and a remarkable 40.6 wt% yield of aromatic monomers from isolated birch lignin under mild conditions. The exceptional catalytic performance originates from synergistic dual‐confinement effects, in which hierarchical porosity enables efficient mass transfer of lignin substrates, whereas N‐doping provides robust chemical anchoring of the ultrafine Ru active sites. Density functional theory calculations further elucidate that electronic modulation at the Ru–N interface significantly lowers the activation energy for C–O bond cleavage. This work demonstrates a high‐efficiency depolymerization protocol and establishes a theoretical framework for designing robust dual‐confined catalysts in macromolecular biomass conversion.