Carbon molecular sieve (CMS) membranes have impressive separation properties; however, both chemical and morphology structures need to be understood better. Here we characterize CMS with the simplest polyimide (PI) PMDA/pPDA (PMDA=pyromellitic dianhydride, pPDA= p ‐phenylenediamine), using FTIR, solid‐state 15 N‐NMR and 13 C‐NMR, XPS, XRD, and Raman spectra to study chemical structure. We also compare gas separation properties for this CMS to a CMS derived from a more conventional PI precursor. The detailed characterization shows the presence of aromatic pyridinic, pyrrolic rings as well as graphitic, pyridonic components and a few other groups in both CMS types derived from the very different precursors. The CMS morphologies, while related to precursor and pyrolysis temperature details, show similarities consistent with a physical picture comprising distributed molecular sieving plate‐like structures. These results assist in understanding diverse CMS membrane separation performance.
Qiu, Wulin, Leisen, Johannes E., Liu, Zhongyun, Quan, Wenying, & Koros, William J. (2021). Key Features of Polyimide‐Derived Carbon Molecular Sieves. Angewandte Chemie, 133(41). https://doi.org/10.1002/ange.202106740
Qiu, Wulin, Leisen, Johannes E., Liu, Zhongyun, et al., "Key Features of Polyimide‐Derived Carbon Molecular Sieves," Angewandte Chemie 133, no. 41 (2021), https://doi.org/10.1002/ange.202106740
@article{osti_1818781,
author = {Qiu, Wulin and Leisen, Johannes E. and Liu, Zhongyun and Quan, Wenying and Koros, William J.},
title = {Key Features of Polyimide‐Derived Carbon Molecular Sieves},
annote = {Abstract Carbon molecular sieve (CMS) membranes have impressive separation properties; however, both chemical and morphology structures need to be understood better. Here we characterize CMS with the simplest polyimide (PI) PMDA/pPDA (PMDA=pyromellitic dianhydride, pPDA= p ‐phenylenediamine), using FTIR, solid‐state 15 N‐NMR and 13 C‐NMR, XPS, XRD, and Raman spectra to study chemical structure. We also compare gas separation properties for this CMS to a CMS derived from a more conventional PI precursor. The detailed characterization shows the presence of aromatic pyridinic, pyrrolic rings as well as graphitic, pyridonic components and a few other groups in both CMS types derived from the very different precursors. The CMS morphologies, while related to precursor and pyrolysis temperature details, show similarities consistent with a physical picture comprising distributed molecular sieving plate‐like structures. These results assist in understanding diverse CMS membrane separation performance. },
doi = {10.1002/ange.202106740},
url = {https://www.osti.gov/biblio/1818781},
journal = {Angewandte Chemie},
issn = {ISSN 0044-8249},
number = {41},
volume = {133},
place = {Germany},
publisher = {Wiley Blackwell (John Wiley & Sons)},
year = {2021},
month = {09}}