Z-Schematic Artificial Leaf-like Structure for Biosolar Oxyfunctionalization of C-H Bonds

The natural Z-schematic photosynthesis is a promising catalytic system for biocatalytic solar-to-chemical production. Here, we construct a Z-schematic, wireless photoelectrocatalytic (PEC) system (i.e., artificial leaf) for biocatalytic oxyfunctionalization reactions. The monolithic leaf structure consists of a tandem photoanode-photocathode configuration that uses sunlight as the sole energy source to drive redox reactions. Under solar light, inorganic oxide photoanode extracts electrons from H₂O electron feedstock and transfers the electrons to the organic photocathode. Meanwhile, the conjugated thiophene based organic photocathode absorbs photoanode-filtered light for O₂ reduction to H₂O₂ with a high faradaic efficiency (76 %) even in neutral pH environments. The <i>in situ</i> generated H₂O₂ activates biocatalytic enzyme to drive C-H oxyfunctionalization (e.g., ethylbenzene oxyfunctionalization) with an excellent enantioselectivity (enantiomeric excess &gt; 99%). Furthermore, we solve hydroxyl radical mediated inactivation of biocatalyst using a membrane, which increases enzymatic productivity with a benchmark total turnover number of about 100,000 among PEC and photocatalytic platforms that trigger biocatalyst mediated synthesis. This work presents the first artificial leaf architecture for enzymatic oxyfunctionalization of C-H bonds.