Anthraquinone-functionalized Bi-based metal-organic frameworks/BiOCl S-scheme heterostructure with enhanced...

The efficiency of photocatalytic H₂O₂ production is substantially hindered by inefficient charge separation and sluggish interfacial reaction kinetics. Herein, a novel strategy involving the covalent conjugation of anthraquinone (AQ) with an in situ-generated Bi-MOF derived from BiOCl through amide bonding was first proposed. The introduction of AQ as a functional unit facilitates the construction of the strong interfacial electric field, optimizing the charge separation efficiency of the BiOCl and Bi-MOF/AQ Step-scheme (S-Scheme) heterostructure. Meanwhile, the AQ moieties act as O₂ reduction centers, capturing photogenerated electrons and transferring them to the O₂ molecules for efficient H₂O₂ production. The optimized BiOCl/Bi-MOF/AQ composite achieves an enhanced photocatalytic H₂O₂ production rate of 1599.76 μmol g^-1 h^-1, which is 8.8, 26.1, and 3.5 times greater than that of BiOCl, Bi-MOF/AQ, and BiOCl/Bi-MOF, respectively. The enhancement of the electric field in the heterojunction was systematically validated through charge density difference and Kelvin Probe Force Microscopy (KPFM). This work presents a promising photocatalytic platform based on a Bi-MOF, offering an available catalytic avenue to develop sustainable H₂O₂ production.