Decoupled Artificial Photosynthesis

Natural photosynthesis (NP) generates oxygen and carbohydrates from water and CO2 utilizing solar energy to nourish lives and balance CO2 levels. Following nature, artificial photosynthesis (AP), typically, overall water or CO2 splitting, produces fuels and chemicals from renewable energy. However, hydrogen evolution or CO2 reduction is inherently coupled with kinetically sluggish water oxidation, lowering efficiencies and raising safety concerns. Decoupled systems have thus emerged. In this review, we elaborate how decoupled artificial photosynthesis (DAP) evolves from NP and AP and unveil their distinct photoelectrochemical mechanisms in energy capture, transduction and conversion. Advances of AP and DAP are summarized in terms of photochemical (PC), photoelectrochemical (PEC), and photovoltaic-electrochemical (PV-EC) catalysis based on material and device design. The energy transduction process of DAP is emphasized. Challenges and perspectives on future researches are also presented.

Automated summary

Natural photosynthesis utilizes solar energy to generate oxygen and carbohydrates from water and CO2, while artificial photosynthesis produces fuels and chemicals from renewable energy through water or CO2 splitting. However, the coupling of hydrogen evolution or CO2 reduction with slow water oxidation reduces efficiencies and raises safety concerns. Decoupled artificial photosynthesis (DAP) has emerged as a solution, and this review explores its evolution from natural and artificial photosynthesis, as well as its distinct mechanisms in energy capture, transduction, and conversion. Advances in DAP are summarized in terms of photochemical, photoelectrochemical, and photovoltaic-electrochemical catalysis, with a focus on the energy transduction process. Challenges and perspectives for future research are also discussed.