Covalent grafting of polyethyleneimine on hydroxylated three-dimensional graphene for superior CO sub(2) capture

Covalently tethered CO sub(2) adsorbents are synthesized by acid catalyzed ring-opening polymerization of aziridine on the basal planes of three-dimensional hydroxylated graphene (HG). The resulting materials possess high surface areas, strong covalent bonds between polyethyleneimine (PEI) and graphene, and high thermal conductivity. The HG-PEI nanocomposites exhibit high amine loading (more than 10.03 mmol N g super(-1)), high adsorption capacity (up to 4.13 mmol CO sub(2) g super(-1) in simulated ambient air under 1 atm of dry CO sub(2)) as well as good stability both at low (100 degree C) and high desorption temperatures (135 degree C), which allows the overall CO sub(2) capture process to be promising and sustainable.