Amino Acid-Functionalized Nanoporous Metal–Organic Frameworks for Boosting CO₂ Capture under Dry and Humid Conditions

Metal–organic frameworks (MOFs), a class of porous materials, featuring high surface areas, chemical tunability and stability, have been extensively studied for their applications in gas adsorption and separation, particularly in carbon dioxide (CO₂) capture. However, their CO₂ capture capacities often decrease under humid conditions and cannot meet practical application requirements. Herein, we present a facile postsynthetic method to incorporate amino acids (AAs) into an ultrastable MIP-206-OH MOF to construct a series of MIP-206-OH-AA materials. Among these materials, MIP-206-OH-Gly exhibited superior CO₂ capture performance, achieving capacities of 48.4 cm³ g^–1 (1 bar, 273 K) and 317 cm³ g^–1 (30 bar, 273 K), which showed 92.8 and 71.9% enhancement compared to the pristine MIP-206-OH materials, respectively. Furthermore, MIP-206-OH-Gly and MIP-206-OH-Ala exhibited enhanced CO₂ capture performance under humid conditions and exhibited exceptional stability, maintaining their performance even after 10 cycles. This study provides a facile method to construct amino acid-functionalized nanoporous MOFs for boosting CO₂ capture and underscores the potential of this strategy as an effective and scalable solution for carbon capture under dry and humid conditions.