Selective Carbon Capture via Pressure Swing Adsorption Using a Facilely Synthesized Adenine-Based Metal–Organic Framework

Developing physisorbents with efficient capture of carbon dioxide (CO2) is crucial for environmental and industrial demands. Here, we report a microporous metal–organic framework, Cu-BA-AD(RT) (BA = butanedioate, AD = adeninate), that can be facilely synthesized on a gram scale through a room-temperature synthetic protocol. Benefiting from abundant Lewis basic sites (specifically, amino groups and noncoordinated N atoms) oriented toward the channels, which serve as moderate binding sites, Cu-BA-AD(RT) demonstrated a CO2 adsorption capacity of 6.79 mmol/g at 298 K and 10 bar, together with outstanding CO2/N2 and CO2/CH4 selectivities. Moreover, Cu-BA-AD(RT) exhibited a moderate isosteric heat of adsorption for CO2 (24.4 kJ/mol), facilitating complete regeneration in the pressure–vacuum swing adsorption (PVSA) process. Molecular simulations reveal that the selective adsorption of CO2 can be ascribed to multiple interactions between Cu-BA-AD and CO2. The robust framework structure and excellent cyclic performance in CO2/N2 and CO2/CH4 separation by actual PVSA processes at 298 K further validate the substantial potential of Cu-BA-AD (RT) for industrial applications.