Energy-efficient membrane technologies are essential for reducing energy consumption and carbon emissions in industrial separations. Two-dimensional (2D) metal-organic framework (MOF) molecular sieve membranes have tunable structures, ultrathin thickness, and customizable pores, which are ideal for applications in gas separation and deionization. However, their development has been limited by time-consuming synthesis processes and inefficient assembly methods.

In a study published in National Science Review, a research team led by Prof. YANG Weishen and Prof. PENG Yuan from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) developed a triggered interfacial synthesis strategy that accelerates the fabrication of high-performance MOF membranes.

The strategy combines confined air-water interfacial nanosheet synthesis with a radial thrust-triggered in situ assembly, which reduces fabrication time from hours or days to just minutes. Besides, this process requires only microliter-scale consumption of organic ligands, which is a cost-effective and scalable way.

Using this strategy, researchers fabricated a Zn-MOF nanosheet membrane that achieved a H₂ and CO₂ separation factor of 210 and hydrogen permeance of 6.2 × 10⁻⁷ mol/m²•s•Pa, outperforming both conventional MOF membranes and commercial alternatives. These results demonstrated the feasibility of on-demand design of ultrathin 2D MOF membranes for industrial applications.

Moreover, this strategy shows remarkable versatility. By flexibly combining different metal ions and organic ligands, researchers synthesized 12 types of MOF nanosheets with distinct framework structures and pore/channel environments, which provides a novel approach for the application-oriented and customizable fabrication across a wide range of eparation scenarios.

"This work not only provides a new strategy for efficiently customization of MOF nanosheets, but also expands the application potential of the ultrathin, flexible 2D materials with high-density, regular pore arrays in material science, device architecture design, separation engineering," said Prof. YANG.