Light-driven CO₂ capture with photoacids from concept to scalable technology

Scalable and affordable CO2 capture is needed to meet climate goals, prompting exploration of approaches beyond thermally and electrically-driven ones. Light-driven CO2 capture using photoacid molecules leverages light to drive CO2 sorbent regeneration, expanding the energy input basis available for carbon capture. Here, we combine bench-scale experiments with process modeling to identify the molecular and process conditions required to scale up light-driven CO2 capture. We reveal that raising the photoacid concentration 100-fold relative to previous demonstrations to >0.3 M would enable >90% CO2 recovery and reduces the electricity demand by an order of magnitude compared to a state-of-the-art amine-based CO2 capture process from a cement plant. This performance gain highlights the promise of light-driven CO2 capture and reveals key targets for further research: improving photoacid solubility and stability to achieve cyclability and near-molar concentrations and optimizing the process design to efficiently handle practical CO2 streams. These findings provide a roadmap for advancing light-driven CO2 capture from proof of concept towards a scalable carbon management technology.