An artificial photosynthesis system based on CeO2 as light harvester and N-doped graphene Cu(II) complex as artificial metalloenzyme for CO2 reduction to methanol fuel

•An artificial photosynthesis system is fabricated.•The system consists of CeO2 semiconductor and N-doped graphene Cu(II) complex metalloenzyme.•Cu(II) complex artificial metalloenzyme is a key component in reducing CO2 to methanol fuel.•A semiconductor coupled with metalloenzyme is regarded as an artificial photosynthesis model.

An artificial photosynthesis catalyst composed of CeO2, N-doped graphene and copper ions (CeO2–NG–Cu2 +) was fabricated. The light-harvesting CeO2–NG was characterized by X-ray diffraction, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The photocatalytic reduction of CO2 was conducted in an aqueous solution of Na2SO3. Results indicated that the reduction rate of CO2 to methanol approached 507.3 μmol · g−1 cat. · h− 1 for CeO2–NG–Cu2 + artificial photosynthesis system in 80 min, whereas the reduction rate was only 5.8 μmol · g−1 cat. · h− 1 for bare CeO2–NG without metalloenzyme. Therefore, artificial metalloenzyme played a vital role in reducing CO2 to methanol fuel.

Graphical abstractAn artificial photosynthesis system reduces CO2 to methanol.Figure optionsDownload full-size imageDownload as PowerPoint slide