Efficient Light-Driven CO2 Capture and Reversible Release Enabled by Metastable Photoacid-Decorated Metal-Organic Frameworks.

Point source carbon capture contributes crucially to climate change mitigation; however, integrating CO2 capture with renewable energy sources to minimize energy consumption for sorbent regeneration and CO2 release poses significant challenges. Photoacid-based systems offer a light-regulated route to CO2 capture and release by using photonic energy to modulate acidity under mild conditions. Herein, efficient photodriven CO2 release systems are realized through the coassembly of amino-functionalized metal-organic frameworks (MOFs) and metastable photoacids. This optimized system released 12 mL of CO2 per mmol photoacid every cycle from flue gas within 3 min of light exposure and regenerates CO2-capture ability during a 5 min dark period. A U-shaped continuous-flow prototype further enabled light-triggered CO2 release, delivering a CO2 release rate of 0.11 mL min-1 from an effluent gas flow of 1.0 mL min-1.