Cooperative carbon capture and steam regeneration with tetraamine-appended metal–organic frameworks

Natural gas has become the dominant source of electricity in the United States, and technologies capable of efficiently removing carbon dioxide (CO₂) from the flue emissions of natural gas-fired power plants could reduce their carbon intensity. However, given the low partial pressure of CO₂ in the flue stream, separation of CO₂ is particularly challenging. Taking inspiration from the crystal structures of diamine-appended metal-organic frameworks exhibiting two-step cooperative CO₂ adsorption, we report a family of robust tetraamine-functionalized frameworks that retain cooperativity, leading to the potential for exceptional efficiency in capturing CO₂ under the extreme conditions relevant to natural gas flue emissions. The ordered, multimetal coordination of the tetraamines imparts the materials with extraordinary stability to adsorption-desorption cycling with simulated humid flue gas and enables regeneration using low-temperature steam in lieu of costly pressure or temperature swings.