Solar-Driven Carbon Dioxide Capture Using a Photoelectrochemical Redox Flow System

Carbon dioxide (CO2) capture is essential for mitigating climate change, but scaling existing technologies to address global CO2 emissions will place significant demands on energy systems. To overcome this challenge, we present a photoelectrochemical flow system using anthraquinone-2,7-disulfonate (AQDS) as a sorbent, which is activated by sunlight to capture CO2 under dark conditions and releases it upon reillumination. This system successfully cycled for 70 h, demonstrating both stability and efficiency. Inspired by solar rechargeable redox flow batteries, the system expands on current solar-driven CO2 capture technologies by enabling CO2 release via photodesorption at 0 V vs OCV. While the system is still in its early stages, it presents a promising addition to the range of photo- and electrically driven CO2 capture methods, with potential for future advancements toward more effective and scalable CO2 capture solutions.