CO2 capture and sequestration is an energy‐intensive industry to deal with the global greenhouse effect. Membrane separation is considered a cost‐effective method to mitigate the emission of CO2. Though good separation performance and stability have been reported, supported ionic liquid membranes are still not widely applied for CO2 separation due to the high cost. As a novel analogous solvent to ionic liquid, deep eutectic solvent retains the excellent merits of ionic liquid and is cheap with facile preparation. Herein, a highly CO2‐philic separation membrane is constructed by nanoconfining choline chloride/ethylene glycol (ChCl/EG) deep eutectic solvent into graphene oxide nanoslits. Molecular dynamic simulation results indicate that the confinement makes a difference to the structure of the nanoconfined ChCl/EG liquid from their bulk, which remarkably facilitates CO2 transport. By tuning the molar ratio of ChCl/EG and thickness of the membrane, the resultant membrane exhibits outstanding separation performance for CO2 with excellent selectivity over other light gases, good long‐term durability, and thermal stability. This makes it a promising membrane for selective CO2 separation.

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Mica has attracted great attention due to its excellent photoelectric property and it is mainly used in the optics and electronics area. High-quality mica nanosheets exfoliated from natural ground mica have been successfully achieved recently. It improves the application potential of mica as well as extending the application field to gas separation as a new two-dimensional (2D) material. Herein, we firstly constructed a mica membrane by regularly stacking mica nanosheets and then immobilized ionic liquid (IL) into its 2D channels to separate CO 2 from H 2 , CH 4 and N 2 . Gas diffusion is changed from Knudsen diffusion in the mica membrane to a solution-diffusion mechanism after inserting IL. The resultant membrane, the mica supported IL membrane (M-SILM), has about 80 GPU for CO 2 permeance, and selectivity for CO 2 /H 2 , CO 2 /CH 4 and CO 2 /N 2 of 7.7, 28.6 and 87, respectively. It is the first time a mica nanosheet to construct a gas separation membrane has been used. As a cheap raw material with facile treating, mica shows promising potential for gas separation and competitiveness among 2D material supported IL membranes.

Fe/N/C catalysts have been regarded as prospective electrocatalysts for oxygen reduction reactions (ORR). As reported, doping S into the Fe/N/C catalyst is an effective strategy to further enhance its ORR performance. Herein, a rational design is demonstrated to synthesize Fe/S/N/C catalysts with a flexible ratio of the doped Fe and S. Through atomic substitution and molecular confinement methods, Fe and S were incorporated into the ZIF-8 precursor, respectively. After further pyrolysis, the Fe/S/N/C catalyst was obtained with uniformly dispersed Fe-Nx, C-S-C active sites and high specific surface area. The Fe/S/N/C catalyst shows a high half-wave potential in alkaline medium, nearly 32 mV higher than the commercial Pt/C, owing to the strong synergistic effect from Fe-Nx and C-S-C active sites. Additionally, the Fe/S/N/C catalyst exhibits good long-term electrocatalytic durability and high endurance to methanol crossover, implying it is a suitable candidate to take the place of conventional Pt or Pt-based catalysts in electrochemical devices.

N-Doped mesoporous carbon catalysts dispersed with Fe3Pt intermetallic nanoparticles, exhibiting excellent ORR performance, were synthesised by direct pyrolysis of Pt–Fe co-functionalized ZIF-8.