Zhang Yiming, Sheng Kai, Wang Zheng, Wu Wenjia, Yin Ben Hang, Zhu Junyong, Zhang Yatao
School of Chemical Engineering, Zhengzhou University, Zhengzhou, 450001, PR China.
MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Natural Sciences, Massey University, Palmerston North, 4410, New Zealand.
Nano Lett. 2023 Apr 12;23(7):2710-2718. doi: 10.1021/acs.nanolett.3c00004. Epub 2023 Mar 16.
One scalable and facile dip-coating approach was utilized to construct a thin CO-selection layer of Pebax/PEGDA-MXene on a hollow fiber PVDF substrate. An interlayer spacing of 3.59 Å was rationally designed and precisely controlled for the MXene stacks in the coated layer, allowing efficient separation of the CO (3.3 Å) from N (3.6 Å) and CH (3.8 Å). In addition, CO-philic nanodomains in the separation layer were constructed by grafting PEGDA into MXene interlayers, which enhanced the CO affinity through the MXene interlayers, while non-CO-philic nanodomains could promote CO transport due to the low resistance. The membrane could exhibit optimal separation performance with a CO permeance of 765.5 GPU, a CO/N selectivity of 54.5, and a CO/CH selectivity of 66.2, overcoming the 2008 Robeson upper bounds limitation. Overall, this facile approach endows a precise controlled molecular sieving MXene membrane for superior CO separation, which could be applied for interlayer spacing control of other 2D materials during membrane construction.
采用一种可扩展且简便的浸涂方法，在中空纤维聚偏氟乙烯（PVDF）基底上构建了一层由聚醚酰胺（Pebax）/聚乙二醇二丙烯酸酯 - 碳化钛（PEGDA - MXene）组成的薄一氧化碳（CO）选择层。对涂层中MXene堆叠层的层间距进行了合理设计并精确控制，使其为3.59 Å，从而能够有效地将CO（3.3 Å）与氮气（N，3.6 Å）和甲烷（CH，3.8 Å）分离。此外，通过将聚乙二醇二丙烯酸酯接枝到MXene层间构建了分离层中的亲CO纳米域，这增强了通过MXene层间的CO亲和力，而非亲CO纳米域由于阻力低则促进了CO的传输。该膜可展现出最佳分离性能，CO渗透率为765.5 GPU，CO/N选择性为54.5，CO/CH选择性为66.2，突破了2008年罗布森上限的限制。总体而言，这种简便方法赋予了一种精确可控的分子筛MXene膜用于卓越的CO分离，这在膜构建过程中可应用于其他二维材料的层间距控制。
