Yale researchers extract ocean- dissolved CO₂ into clean fuels

In New Jersey, the ocean serves as Earth’s largest dynamic carbon sink, absorbing 400 million tons of carbon dioxide (CO₂) annually through continuous exchange with the atmosphere. Researchers at Yale have now developed an efficient system to extract and convert dissolved CO₂ into clean fuels and useful industrial feedstock. Published in Nature Communications, this breakthrough could transform seawater into a sustainable source for carbon-based products while helping balance oceanic CO₂ levels.

Based on the group’s expertise in designing photocatalysis and the reactor that maximize the use of light for chemical transformation, they developed a new photoelectrochemical device. It uses only sunlight to turn dissolved carbon in seawater—mainly bicarbonate—into syngas. The process mimics how photosynthesis works in ocean ecosystems and reaches a solar-to-fuel efficiency of 0.71%, which is similar to how well seaweed converts carbon. Even more striking is the team’s discovery that, despite the close-to-zero concentration of carbonate in seawater, the selectivity of the reaction can be dramatically influenced by the flow field within the reactor. In static seawater, the CO content in the product was just 3%. However, under the controlled flow conditions inside the reactor, the CO proportion surged to 21%.