2023-10-04 スイス連邦工科大学ローザンヌ校(EPFL)
◆EPFLの研究チームは、MOFフィルムを開発し、水素-窒素の分離に優れた性能を示しました。このフィルムは超薄く、高い効率のガス分離に可能性があります。
<関連情報>
- https://actu.epfl.ch/news/ultrathin-films-achieve-record-hydrogen-separation/
- https://www.nature.com/articles/s41563-023-01669-z
膜応用のためのユニットセル厚ゼオライトイミダゾレート骨格膜 Unit-cell-thick zeolitic imidazolate framework films for membrane application
Qi Liu,Yurun Miao,Luis Francisco Villalobos,Shaoxian Li,Heng-Yu Chi,Cailing Chen,Mohammad Tohidi Vahdat,Shuqing Song,Deepu J. Babu,Jian Hao,Yu Han,Michael Tsapatsis &Kumar Varoon Agrawal
Nature Materials Published:21 September 2023
DOI:https://doi.org/10.1038/s41563-023-01669-z
Abstract
Zeolitic imidazolate frameworks (ZIFs) are a subset of metal–organic frameworks with more than 200 characterized crystalline and amorphous networks made of divalent transition metal centres (for example, Zn2+ and Co2+) linked by imidazolate linkers. ZIF thin films have been intensively pursued, motivated by the desire to prepare membranes for selective gas and liquid separations. To achieve membranes with high throughput, as in ångström-scale biological channels with nanometre-scale path lengths, ZIF films with the minimum possible thickness—down to just one unit cell—are highly desired. However, the state-of-the-art methods yield membranes where ZIF films have thickness exceeding 50 nm. Here we report a crystallization method from ultradilute precursor mixtures, which exploits registry with the underlying crystalline substrate, yielding (within minutes) crystalline ZIF films with thickness down to that of a single structural building unit (2 nm). The film crystallized on graphene has a rigid aperture made of a six-membered zinc imidazolate coordination ring, enabling high-permselective H2 separation performance. The method reported here will probably accelerate the development of two-dimensional metal–organic framework films for efficient membrane separation.