Construction of An Artificial Photosynthesis System with A Single CdS QDs-Ferritin Hybrid Molecule

Establishing artificial photosynthesis systems in a simple but effective manner to mitigate the greenhouse effect and address the energy crisis remains challenging. The combination of photocatalysis technology with bioengineering is an emerging field with great potential to construct such artificial photosynthesis systems, but so far, it has barely been explored in this area. Herein, an artificial photocatalysis platform is constructed with high CO₂ conversion and H₂O splitting capability by integration of CdS QDs into the intra-subunit interface of H-type ferritin (Marsupenaeus japonicus), a natural ferroxidase through protein interface redesign. The crystal structure of the synthesized CdS QDs with engineered ferritin molecules as bio-templates confirmed the design at an atomic level. Notably, upon absorbing desirable visible light (≈420 nm), such a single CdS-ferritin hybrid molecule is able to selectively catalyze the reduction of CO₂ into HCOOH (≈90%), meanwhile catalyzing the oxidation of H₂O into O₂ in an aqueous environment. The O₂ production rate reached to 180 µmol g^-1 h^-1, and the HCOOH output hit almost 800 µmol g^-1 h^-1. This work advances the utilization of the four-helix bundle structure for crafting artificial photosynthesis systems, facilitating the seamless integration of bioengineering and photocatalysis technology.