Ultrahigh permeance metal coated porous graphene membranes with tunable gas selectivities

Membranes play an important role in gas separation on account of their low cost, energy efficiency, and durability. Gas-separation membranes, however, are subject to permeability-selectivity trade-off, i.e., atomically thin 2D materials such as porous graphene can provide ultrahigh permeances in the range of similar to 10(5)-10(7) GPU but suffer from low gas selectivity. Here, we show a new concept to enhance the selectivity of graphene-based membranes by employing adsorptive separation for binary gas mixtures. The deposition of microislands'' of Pd and Ni on the porous double-layer graphene support allowed us to selectively target H-2 in He/H-2 and CO2 in H-2/CO2 mixtures, respectively, thus enabling efficient separation of He and also leading to the highest H-2/CO2 separation factor of 26 within the similar to 10(5) GPU permeance range. Moreover, the selective targeting of individual gases in amembrane setting through adsorptive separation at room temperature can be a promising alternative for economical gas separation.

Automated summary

Membranes are crucial in gas separation for their low cost, energy efficiency, and durability. Researchers have developed a new concept to enhance selectivity of graphene-based membranes by depositing microislands of Pd and Ni on the support layer, enabling efficient separation of specific gases like H2 and CO2. This approach may offer a promising alternative for economical gas separation by selectively targeting individual gases in a membrane setting through adsorptive separation at room temperature.