In situ generation of intercalated membranes for efficient gas separation

Abstract

Membranes with well-defined pore structure which have thin active layers may be promising materials for efficient gas separation. Graphene oxide (GO) materials have potential applications in the field of membrane separation. Here we describe a strategy for the construction of ultra-thin and flexible HKUST-1@GO intercalated membranes, where HKUST-1 is a copper-based metal–organic framework with coordinatively unsaturated metal sites, with simultaneous and synergistic modulation of permeance and selectivity to achieve high H2/CO2 separation. CuO nanosheets@GO membranes are fabricated layer-by-layer via repeated filtration cycles, then transformed to HKUST-1@GO membranes upon in situ reaction with linkers. The HKUST-1@GO membranes show enhanced performance for gas separation of H2/CO2 mixture. The number of filtration cycles is optimized to obtain H2 permeance of 5.77 × 10−7 mol m−2 s−1 Pa−1 and H2/CO2 selectivity of 73.2. Our work provides a facile strategy for the construction of membranes based on metal–organic frameworks and GO, which may be applied in the preparation of flexible membranes for gas separation applications.