Direct air capture (DAC): molten carbonate direct transformation of airborne CO2 to durable, useful carbon nanotubes and nano-onions†

This study introduces the concept and first demonstration of an effective molten carbonate chemistry for Direct Air Capture (DAC). Molten carbonate electrolysis is a high-temperature decarbonization process within Carbon Capture, Utilization and Storage (CCUS) that transforms chemistry transforming flue gas CO₂ into carbon nanotubes and carbon nano-onions. The key challenge for molten carbonate DAC is to split air's 0.04% CO₂ without heating the remaining 99.6%. This is accomplished by integrating a diffusive, insulating membrane over an electrolyte with a high affinity for CO₂.