Exceptional CO₂ working capacity in a heterodiamine-grafted metal–organic framework

Abstract

An amine-functionalized metal-organic framework (MOF), dmen-Mg₂(dobpdc) (dmen = <i>N</i>,<i>N</i>-dimethylethylenediamine), which contains a heterodiamine with both primary and tertiary amines, was prepared <i>via</i> a post-synthetic method. This material exhibits a significant selectivity factor for CO₂ over N₂ that is commensurate with top-performing MOFs. It is remarkable that the solid is fully regenerated under vacuum or flowing Ar at low desorption temperatures, and following this can take up CO₂ at more than 13 wt%. An exceptionally high working capacity is achieved at low regeneration temperatures and after exposure to humid conditions, which are important parameters for a real post-combustion CO₂ capture process.