Pretreatment-RegulatedStructural Evolution and DynamicCu–CoOx Interfaces for Enhanced C–O Bond Hydrogenolysisof Zhaotong Lignite

Efficient depolymerization of lignite remains challenging owing to both its structural complexity and the high stability of oxygen-containing bridge linkages. Herein, low-temperature pyrolysis and oxidative pretreatments were employed to regulate oxygen-containing structures and enhance the hydrogenolysis reactivity of Zhaotong lignite (ZT). These pretreatments promoted the structural evolution of lignite, activated oxygen-containing bridge structures, and suppressed the recondensation of reactive intermediates, thereby facilitating subsequent depolymerization reactions. A CuCoOx catalyst capable of dynamic in situ reconstruction was introduced for catalytic hydrogenolysis. Under reaction conditions, partial reduction of CuCoOx generated reconstructed Cu0-CoOx interfacial active sites, where the synergistic interaction between metallic Cu and defect-rich CoOx promoted H2 activation and selective C–O bond cleavage. Density functional theory (DFT) calculations further revealed that interfacial electron redistribution at the Cu cluster/Vo-Co3O4 (311) interface facilitated H2 activation and stabilized reactive hydrogen species. These findings provide new mechanistic insights into pretreatment-regulated and interface-controlled hydrogenolysis pathways for the efficient valorization of low-rank coal.