▎ 摘　　要

Reduced graphene oxide (rGO) membranes have shown promising separation and purification in the fields of water treatment and gas capture due to their unique physicochemical characteristics. However, how to further reduce the transport resistance of rGO membranes and improve separation performance is still a thorny issue. In this work, the reported metal-crosslinked rGO membranes showed a reverse-selective separation behaviors for the adsorbed gas molecules at low pressure. The effect of metal ions on the membrane structure and the separation performance were investigated. Metal ions not only can improve the cross-linking structure and control interlamellar spacing of rGO membranes for the precise molecular sieve, but also can provide abundant metal sites to enhance the affinity, which led to a diffusion-controlled process for the targeted gas molecules. The resulting metal-crosslinked rGO membranes presented outstanding gas permeance and selectivity for gas pairs of the He/CO2, N2/CO2 and Kr/Xe, with the highest selectivity of 21, 11.4 and 4.1, respectively. The work will provide a new avenue towards specific molecule capture for the development of rGO membranes in the fields of natural gas purification and radioactive gas recovery.