A facile strategy for fabrication of HKUST-1 on a flexible polyethylene nonwoven fabric with a high MOF loading

Fabrication of metal-organic frameworks (MOFs) on polymer substrates has significant potential in the fields of adsorption, separation and catalysis. However, the loading of MOF and the stability of polymer/MOF composites require effective improvement, which remains a great challenge. In this work, a copper benzene-1,3,5-tricarboxylate MOF HKUST-1 (HK) is fabricated on a flexible polyethylene (PE) nonwoven fabric (NWF) with a high loading of 66 wt%. The synthesis of polyethylene-g-poly(acrylic acid)/HK (PE-g-PAA/HK) NWF including radiation grafting of acrylic acid (AA), adsorption of copper(II) (Cu2+) ions, and solvothermal growth process. Scanning electron microscopy images confirm that the surface of the grafted PE NWF substrate is completely covered by the HK crystals. Moreover, the loaded HK crystals present well-controlled morphology and uniform crystal size distribution. Owing to the porous structures of HK, the fabricated PE-g-PAA/HK NWF maintains a high Brunauer-Emmett-Teller (BET) surface area of 758.1 m2 g−1 and exhibits a good CO2 adsorption capacity of 2.23 mmol g−1 (101 kPa, 25 °C). The proposed radiation grafting combined activation process can be viewed as a facile strategy for fabrication of MOFs on flexible polymer substrates with a high MOF loading.