Amino-Functionalized Metal–Organic Framework Fiber Membranes for CO<sub>2</sub> Adsorption
Guodong Zhao, Tongtong Zhang, Siqin Zhang, Huijuan Zhao
Abstract
Metal–organic frameworks (MOFs) have attracted attention for CO 2 adsorption owing to their unique pore characteristics and facile functionalization. However, their powdery nature causes poor mechanical stability and low gas mass transfer efficiency, limiting their applications. Herein, we report a promising strategy of in situ assembly of amino-functionalized ZIF-8 (ZIF-8-NH 2 ) on the surface of nanofibers to create the one-dimensional gas transport pathway while generating hierarchical porous architectures that increase the number of CO 2 -philic sites. Benefiting from the created microenvironments, the ZIF-8-NH 2 fiber membranes (FMs) showed a high specific surface area of 248.29 m 2 /g, a high CO 2 adsorption capacity of 3.25 mmol/g at 298 K and 1 bar, an excellent CO 2 /N 2 selectivity of 37, and stable recyclability. Molecular dynamics simulations indicated that amination could enhance the CO 2 affinity of ZIF-8-NH 2 FMs. The gas dynamic breakthrough tests further demonstrated the high separation efficiency of the ZIF-8-NH 2 FMs for the formation of CO 2 and N 2 . The proposed collaborative regulation of microenvironments strategy provides a bright orientation for constructing functionalized MOF FMs for efficient CO 2 adsorption.