Synergistic engineering of oxygen vacancies and AuCu interface on ZnO for enhanced photocatalytic biomass valorization

A dual-regulation strategy integrating O V engineering and AuCu bimetallic synergy is developed for ZnO photocatalysts. • The optimal Cu 2 Au 2.6 /O V -ZnO delivers a coupling yield of 2625.0 μmol·g −1 ·h −1 , 4.0 and 11 times that of Cu/ZnO and Au/ZnO. • Heterogeneous photocatalysis enables flexible C(sp 3 )–C(sp 3 )-bridged bifuran synthesis, breaking long-standing bottlenecks. • The synergistic mechanism is clarified, and the bifuran monomers are directly applicable for bio-based polyester fabrication. The photocatalytic C C coupling of furanic platform molecules represents a green and sustainable route to valorization of biomass into high-value chemicals. Nevertheless, this process is frequently plagued by low efficiency owing to rapid charge recombination and insufficient catalytic activity. Herein, we report a highly efficient photocatalyst, Cu Au bimetal supported on oxygen vacancy-rich ZnO (Cu 2 Au 2.6 /O V -ZnO), for the light-driven coupling of furfuryl chloride derivatives into a bifuran monomers. A combination of oxygen vacancy (O V ) engineering and bimetallic synergy was employed to optimize the performance of the catalyst. Systematic characterization, including SEM/TEM, XPS, UV–vis, EPR, PL/TRPL, and KPFM, revealed that O V sites enhance visible light absorption and serve as electron traps, whereas the Cu Au bimetallic system forms a Schottky heterojunction, collectively promoting the separation and migration of photogenerated electron-hole pairs. The optimized Cu 2 Au 2.6 /O V -ZnO catalyst achieved an exceptional yield of 2625.0 μmol·g −1 ·h −1 , which is approximately 4.0 and 11.0 times greater than those of the monometallic Cu 2 /ZnO and Au 2 /ZnO catalysts, respectively. Mechanistic studies confirmed the crucial roles of both photogenerated electrons and holes, with photogenerated electrons facilitating the critical reductive steps. This work provides a strategic design of multifunctional photocatalysts through defect and interface engineering for efficient biomass conversion to high-value monomers. Download: Download high-res image (179KB) Download: Download full-size image