In-situ crystallization of CALF-20 nanoparticles in poly(acrylate) with enhanced CO2 capture capability toward high-humidity flue gases

Abstract

To extend the application range of Calgary framework-20 (CALF-20, Zn2(1,2,4-triazolate)2(oxalate)), an in-situ crystallization method was used to synthesize spherical CALF-20@poly(acrylate) composite. Owing to the inhomogeneous nucleation induced by nano-ZnC2O4 in poly(acrylate), the size of CALF-20 was reduced to 100–200 nm, forming a carbophilic/hydrophobic functional composite with a macroporous/microporous coupling structure. Compared with the original powder, the adsorption efficiency of the CALF-20 nanocrystals in poly(acrylate) improved by 32 %. In a penetration experiment (10 vol% CO2/90 vol% N2 and 90 % relative humidity), the composite retained 97.1 % of its dry CO2 uptake capacity. The dynamic selectivity of CO2/N2 reached 77.5, which was 2.2 times higher than that of the CALF-20 powder. These results demonstrate that CALF-20@poly(acrylate) can be applied to high-humidity flue gases.