Amidation-Reaction Strategy Constructs Versatile Mixed Matrix Composite Membranes towards Efficient Volatile Organic Compounds Adsorption and CO2 Separation

Mixed matrix composite membranes (MMCMs) have shown advantages in reducing VOCs and CO2 emissions. Suitable composite layer, substrate, and good compatibility between the filler and the matrix in the composite layer are critical issues in designing MMCMs. This work develops a high-performance UiO-66-NA@PDMS/MCE for VOCs adsorption and CO2 permea-selectivity, based on a simple and facile fabrication of composite layer using amidation-reaction approach on the substrate. The composite layer shows a continuous morphological appearance without interface voids. This outstanding compatibility interaction between UiO-66-NH2 and PDMS is confirmed by molecular simulations. The SiO functional group and UiO-66-NH2 in the layer leads to improved VOCs adsorption via active sites, skeleton interaction, electrostatic interaction, and van der Waals force. The layer and CONH also facilitate CO2 transport. The MMCMs show strong four VOCs adsorption and high CO2 permeance of 276.5 GPU with a selectivity of 36.2. The existence of VOCs in UiO-66-NA@PDMS/MCE increases the polarity and fine-tunes the pore size of UiO-66-NH2, improving the affinity towards CO2 and thus promoting the permea-selectivity for CO2, which is further verified by GCMC and EMD methods. This work is expected to offer a facile composite layer manufacturing method for MMCMs with high VOC adsorption and CO2 permea-selectivity.