Processing and Separation Performance Principles of Zeolitic Imidazolate Framework Membranes

Metal-organic frameworks (MOFs) hold promise as gas separation membranes due to their tunable permeation properties enabled by the structural diversity stemming from the plethora of available metal/organic combinations. Among MOFs, zeolitic imidazolate frameworks (ZIFs) have been studied extensively for their potential as selective separation membranes because their unique structural properties allow them to achieve high performance for certain important separations, like that of propylene from propane. Although relatively rapid progress for highly selective ZIF membranes has been achieved, reliable and scalable thin film processing remains a challenge.[1] In this talk, I will discuss synthesis and post-synthesis modification methods we have been developing based on vapor and liquid phase processing and use of electron-beam-, X-ray- and plasma-induced modifications.[2-5] These methods establish a new materials processing paradigm for thin film separation membranes that could allow control of structure, and composition to achieve optimal separation performance. Recent results on

membranes based on amorphous ZIFs (aZIF) made by molecular layer deposition and microfluidic deposition will be discussed.

1. Lee D.T., et al. Annual Review of Chemical and Biomolecular Engineering 13, 529-555 (2022)

2. Ma X., et al. Science 361, 1008-1011 (2018)

3. Eum K., et al. Angewandte Chemie Int. Ed. 58, 16390-16394 (2019)

4. Miao Y., et al. Chemical Communications 60, 9316-9320 (2021)

5. Hayashi M., et al. Angewandte Chemie Int. Ed. 60, 9316-9320 (2021)