Molecular‐Bridged Core–Shell TiO ₂ @CuFe Conductive Metal–Organic Framework Photoanode for Hydroxyl Radical‐Mediated Selective Glycerol Oxidation to Glyceraldehyde

The solar-driven photoelectrochemical (PEC) oxidation of glycerol to value-added C₃ products faces challenges due to the rapid charge recombination and unfavorable CC bond cleavage. This study presents a novel strategy through the rational design of a core-shell TiO₂@CuFe-cMOF photoanode, where caffeic acid (CA) serves as a bifunctional molecular bridge to engineer a conformal, atomically coherent heterojunction interface. The unique architecture significantly enhances interfacial charge transport, suppresses carrier recombination, and promotes the selective generation of hydroxyl radicals (·OH) as the primary oxidant. Under AM 1.5 G illumination , the optimized photoanode achieves remarkable performance metrics: a photocurrent density of 1.67 mA cm^-2 at 1.0 V_RHE (~3.2-fold higher than pristine TiO₂), together with glyceraldehyde (GLD) and 1,3-dihydroxyacetone (DHA) yields of 108 and 35.3 mmol m^-2 h^-1, representing ~3.0 times and ~2.3 times improvements over bare TiO₂, respectively. The results reveal that the reaction proceeds dominantly via ·OH-mediated CH activation, with the CA-bridged core-shell structure effectively steering the reaction pathway toward valuable C₃ products while suppressing over-oxidation to C₁ byproducts. This study demonstrates the critical role of ligand-mediated interfacial engineering in designing efficient heterostructured photoanodes and establishes a sustainable paradigm for valorizing biomass-derived feedstocks through solar energy conversion.