Gated Transport of CO₂ through Electrowetted Solid-State Nanopores

Various investigations have demonstrated that porous solid-state membranes have great potential for CO₂ separation, and remarkable progress has been achieved. To date, researchers have usually focused on solid-state nanopores (e.g., C6) with sizes comparable to those of the transported gases due to their specific gas–pore interactions and therefore desirable performance, while overlooking large nanopores that are inevitably present in a fabricated porous membrane.

It is well-known that a large nanopore (e.g., C24) can lose its selectivity because of the effortless transport of both CO₂ and its mixtures (attributed to the trade-off between permeation and selectivity). Therefore, maintaining a high selectivity for CO₂ through large solid-state nanopores remains a great challenge. Here, we present the design of a CO₂/N₂ separation system based on water-covered graphene nanochannels (C24) in an electric field.