Designing GO Channels with High Selectivity for CO2/N2 Separation via Incorporating Metal Ions

Graphical Metal ions are successfully incorporated into GO channels , which contribute to facilitating CO 2 transport, decreasing N 2 solubility, hindering N 2 diffusion, and form multiple interactions with GO nanosheets, thus achieving the remarkably improved CO 2 /N 2 separation performance (with separation factor increasing 12.2 times) and excellent long-term stability. Graphene oxide (GO) membranes holds great potential for high-performance CO 2 capture. Aiming at enhancing the CO 2 separation performance and structural stability of GO membranes, functionalizing GO channels with metal ions confers a promising strategy. In this study, we reported the fabrication of metal ion-incorporated GO membranes with remarkably improved CO 2 /N 2 separation performance. The metal ions within GO channels contribute to facilitating CO 2 transport, decreasing N 2 solubility, hindering N 2 diffusion, and form multiple interactions with GO nanosheets. After introducing Mg 2+ ions, the CO 2 /N 2 separation factor of GO membrane is remarkably increased from 4 to 48.8 with the CO 2 permeance increases 1.5 times. Moreover, the separation performance of the GO-Mg 2+ membranes shows an excellent long-term stability owing to the structural robustness. This study could provide insights into the regulation of the microstructure of metal ion-functionalized GO membranes for highly selective transport of specific molecules.