A cluster-nanozyme-coenzyme system mimicking natural photosynthesis for CO₂ reduction under intermittent light irradiation.

Abstract

Natural photosynthesis utilizes solar energy to convert water and atmospheric CO₂ into carbohydrates through all-weather light/dark reactions based on molecule-based enzymes and coenzymes, inspiring extensive development of artificial photosynthesis. However, development of efficient artificial photosynthetic systems free of noble metals, as well as rational integration of functional units into a single system at the molecular level, remain challenging. Here we report an artificial system, the assembly system of Cu₆ cluster and cobalt terpyridine complex, that mimics natural photosynthesis through precise integration of nanozyme complexes and ubiquinone (coenzyme Q) on Cu₆ clusters. This biomimetic system efficiently reduces CO₂ to CO in light reaction, achieving a production rate of 740.7 μmol·g^-1·h^-1 with high durability for at least 188 hours. Notably, our system realizes the decoupling of light and dark reactions, utilizing the phenol-evolutive coenzyme Q acting as an electron reservoir. By regulating the stabilizer of coenzyme Q, the dark reaction time can be extended up to 8.5 hours, which fully meets the natural day/night cycle requirements. Our findings advance the molecular design of artificial systems that replicate the comprehensive functions of natural photosynthesis.