Interfacially Stable MOF Nanosheet Membrane with Tailored Nanochannels for Ultrafast and Thermo-Responsive...



Wei Jia, Baohu Wu, Shengtong Sun*, and Peiyi Wu*. Interfacially Stable Mof Nanosheet Membrane with Tailored Nanochannels for Ultrafast and Thermo-Responsive Nanofiltration. Nano Res. 2020, 13, 2973-2978.




Two-dimensional nanosheet membranes with responsive nanochannels are appealing for controlled mass transfer/separation, but limited by everchanging thicknesses arising from unstable interfaces. Herein, an interfacially stable, thermo-responsive nanosheet membrane is assembled from twin-chain stabilized metal-organic framework (MOF) nanosheets, which function via two cyclic amide-bearing polymers, thermo-responsive poly(N-vinyl caprolactam) (PVCL) for adjusting channel size, and non-responsive polyvinylpyrrolidone for supporting constant interlayer distance. Owing to the microporosity of MOF nanosheets and controllable interface wettability, the hybrid membrane demonstrates both superior separation performance and stable thermo-responsiveness. Scattering and correlation spectroscopic analyses further corroborate the respective roles of the two polymers and reveal the microenvironment changes of nanochannels are motivated by the dehydration of PVCL chains.