Tailoring the microporosity of intrinsically microporous polymers at the atomic level is one of the biggest challenges in achieving high-performance polymeric gas separation membranes. In this study, for the first time, the Al2 O3 atomic layer deposition (ALD) technique was used to modify the microporosity of a typical polymer of intrinsic microporosity (PIM-1) at the atomic level. PIM-1 with six ALD cycles (PIM-1-Al2 O3 -6) exhibited simultaneous high thermal, mechanical, pure- and mixed-gas separation, and anti-aging properties. The O2 /N2 , H2 /N2 , and H2 /CH4 separation performances were adequate above the latest trade-off lines. PIM-1-Al2 O3 -6 showed CO2 and O2 permeabilities of 624 and 188 Barrer, combined with CO2 /CH4 and O2 /N2 selectivities of 56.2 and 8.8, respectively. This significantly enhanced performance was attributed to the strong size sieving effect induced by the Al2 O3 deposition.
Keywords: Al2O3; PIM-1; atomic layer deposition; gas separation; membranes.
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