Abstract：
One scalable and facile dip-coating approach was utilized to construct a thin CO2-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 CO2 (3.3 Å) from N2 (3.6 Å) and CH4 (3.8 Å). In addition, CO2-philic nanodomains in the separation layer were constructed by grafting PEGDA into MXene interlayers, which enhanced the CO2 affinity through the MXene interlayers, while non-CO2-philic nanodomains could promote CO2 transport due to the low resistance. The membrane could exhibit optimal separation performance with a CO2 permeance of 765.5 GPU, a CO2/N2 selectivity of 54.5, and a CO2/CH4 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 CO2 separation, which could be applied for interlayer spacing control of other 2D materials during membrane construction.
摘要：
利用一种可扩展且容易的浸涂方法在中空纤维PVDF基材上构造Pebax/PEGDA-MXene的薄CO2选择层。为涂层中的MXene叠层合理设计并精确控制了3.59µ的层间间距，允许将CO2（3.3µ）与N2（3.6µ）和CH4（3.8µ）有效分离。此外,通过将PEGDA接枝到MXene夹层中，构建了分离层中的亲CO2纳米域，增强了通过MXene夹层的CO2亲和力，而非亲CO2的纳米域由于低电阻而可以促进CO2的传输。该膜可以表现出最佳的分离性能，CO2渗透率为765.5GPU，CO2/N2选择性为54.5,CO2/CH4选择性为66.2,克服了2008年罗伯逊上限限制。总的来说,这种简便的方法赋予了精确的受控分子筛MXene膜，以实现出色的CO2分离，可用于膜构建过程中其他2D材料的层间间距控制。
