Tunable hydrocarbon adsorption based on a zeolitic imidazolate framework in the sodalite topology

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 1; no. 3; pp. 1425 - 1432
• Main Authors: Falkowski, Joseph M, Ravikovitch, Peter I, Abdulkarim, Mary S, Muraro, Giovanni M, Liu, Sophie F, Paur, Charanjit, Strohmaier, Elisa A, Weston, Simon C
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 18.01.2022
• Subjects: Adsorption; Crystal structure; Metal-organic frameworks; phase transition; Phase transitions; Sodalite; Topology; Zeolites
• ISSN: 2050-7488; 2050-7496; 2050-7496
• DOI: 10.1039/d1ta00149c

Manipulation of materials exhibiting step-shaped isotherms using simple and scalable methods is key to realizing their utility in advanced separation schemes. To this end, we have discovered EMM-36, a hybrid isostructural to ZIF-7 material in the sodalite topology prepared from industrially scalable organic moieties. Through simple compositional tuning of EMM-36 that remains true to the linker composition introduced in the synthesis, controlled manipulation of the step-function adsorption behaviour of gases onto the flexible framework has been realized. We observe that the energetics for the phase transformation from a denser narrow pore (np) to more open large pore (lp) phase are directly controllable while maintaining the hexagonal crystal structure characteristic of the lp phase of ZIF-7 under adsorbed conditions throughout the entire hybrid compositional range. The structural flexibility of ZIF-7 is controlled via a mixed-linker approach resulting in modified adsorption properties tunable across 2 orders of magnitude of step pressure while maintaining the ZIF-7 structure throughout the compositional range.