Biomimetic MXene membranes with negatively thermo-responsive switchable 2D nanochannels for graded molecular sieving

• DOI: 10.1016/j.gee.2023.01.004
• Publication Date: 2023-01-25T14:02:18Z
• Authors: Yi Wang; Yangyang Wang; Chang Liu; Dongjian Shi; Weifu Dong; Baoliang Peng; Liangliang Dong; Mingqing Chen
• Keywords: Permeance; Nanofluidics; POPC

Negatively thermo-responsive 2D membranes, which mimic the stomatal opening/closing of plants, have drawn substantial interest for tunable molecular separation processes. However, these membranes are still restricted significantly on account low water permeability and poor dynamic tunability nanochannels under temperature stimulation. Here, we present a biomimetic negatively MXene membrane by covalently grafting poly (N-isopropylacrylamide) (PNIPAm) onto nanosheets. The uniformly grafted PNIPAm polymer chains can enlarge interlayer spacings increasing while also allowing more enhancing capability gradually separating multiple molecules different sizes. As expected, constructed exhibits ultrahigh permeance 95.6 L m−2 h−1 bar−1 at 25 °C, is eight-fold higher than state-of-the-art membranes. Moreover, highly temperature-tunable enables to perform excellent graded sieving dye- antibiotic-based ternary mixtures. This strategy provides new perspectives in engineering smart expands scope temperature-responsive showing promising applications micro/nanofluidics separation.