The lamellar MOFs@polymer networks hybrids fabricated in reversed microemulsion for efficient CO2 capture

ZIF-8@polymer networks hybrids (ZIF-8@PNs), consisting of the flexible CO2 responsive polymer and rigid ZIF-8 crystals, were fabricated using DMAPMA as the monomer and BIS as the cross-linker by the reversed microemulsion polymerization, and characterized by the powder XRD, SEM, TEM, DLS, FT-IR, and TGA. Monomers and cross-linkers were initiated by AIBN to form polymer networks which coated ZIF-8 crystals. The shape of ZIF-8@PNs was modulated by the micelles of surfactant in the reversed microemulsion. In particular, the lamellar ZIF-8@PNs hybrids with the regular thickness of 50-70 nm in which ZIF-8 crystals were wrapped by the flexible polymer networks and still retained the crystal skeleton, were fabricated at the high concentration of surfactant in the reversed microemulsion. Additionally, the adsorption capacity of ZIF-8@PNs hybrids for CO2 has been evaluated. Under the higher initial pressure at the lower temperature, the adsorption of ZIF-8@PNs for CO2 was higher than that of the pure ZIF-8, and was an increasing of 180%. The adsorption kinetic models of ZIF-8@PNs for CO2 indicated that CO2 was efficiently captured in the pores of ZIF-8 in the internal and the flexible polymer networks on the surface of ZIF-8@PNs. Moreover, ZIF-8@PNs had good regeneration of CO2 adsorption, and remained more than 90% after 6 cycles.