In summary, Park and co-workers have merged Mo:BiVO₄ photoelectrocatalysis with enzyme catalysis, using HCO₃⁻ as a redox mediator, to achieve stereoselective oxyfunctionalization of C–H bonds.Given the versatility of enzymes in oxidation reactions, photoelectrocatalysis holds considerable untapped potential. As in PSII, redox mediators are key to the success of this scheme, as they relieve the oxidative pressure on the enzymes. In short, redox mediators — whether organic or inorganic — link photoinduced electron transfer with the best of redox catalysis across domains, turning solar energy into a tool for challenging and impactful selective organic transformations. However, precise spatio-temporal control of local concentration of H₂O₂ is critical to preventing gradual oxidative deactivation, thereby ensuring the long-term stability of the enzyme under continuous photoelectrochemical operation. Looking ahead, expanding the repertoire of robust redox mediators and engineering more resilient oxygenative biocatalysts could unlock a range of valuable transformations.