Coupling atomic layer deposition with supercritical fluid processing to provide a highly C3H6‐selective ZIF‐8 membrane.

Zeolitic Imidazolate Framework‐8 (ZIF‐8) membrane is well recognized for its great capability in efficient C3H6/C3H8 separation, and their sustainable fabrication is extremely advantageous for batch production and commercial application. In this study, a solvent‐free protocol was developed for sustainable production of ZIF‐8 membranes with exceptional C3H6/C3H8 selectivity through combining atomic layer deposition (ALD) technique with in situ supercritical fluid (SCF) processing. Experimental results indicated that maintaining appropriate deposition number and conducting SCF processing in gas‐like supercritical carbon dioxide region were crucial for obtaining ZIF‐8 membranes with excellent C3H6/C3H8 selectivity (~185), one of the highest among ZIF‐8 membranes reported in the literature. Noteworthy, not only residual 2‐methylimidazole ligands along with vented gaseous CO2 could be fully recycled and repetitively utilized, but also obsoleting ZIF‐8 membranes could be effectively patched upon SCF‐based treatment. The above‐mentioned solvent‐free protocol holds great application prospects for sustainable production of diverse high‐performance metal–organic framework membranes. [ABSTRACT FROM AUTHOR]