Hybrid Dimensional MXene/CNC Framework-Regulated Nanofiltration Membrane with High Separation Performance: Fid-Bau Portal

Hybrid Dimensional MXene/CNC Framework-Regulated Nanofiltration Membrane with High Separation Performance

Gao, Haiping / Chen, Yongsheng

Thin film composite (TFC) nanofiltration (NF) has been of great interest in water treatment and resource recovery. Nevertheless, the separation performance of TFC NF membranes is limited by their intrinsic permeability-selectivity trade-off. In this study, we present the fabrication of a TFC NF membrane by introducing a hybrid dimensional MXene/CNC framework serving as an interlayer. This hybrid dimensional interlayer regulated the interfacial polymerization process, resulting in a textured surface structure with large surface area and a highly cross-linked polyamide (PA) network. Importantly, the intercalation of CNC into the MXene stack alleviated the constraint of the tortuous water pathways in the 2D channels, promoting the gutter effect of the MXene/CNC interlayer. The enlarged membrane surface area together with the gutter effect of the highly permeable interlayer contributed to the substantially enhanced water permeability (31.68 LMH bar^–1) without compromising the rejection of various salts (99.51% for Na₂SO₄) and antibiotics (>80%). Therefore, the tailored PA-MxC₃₅ membrane could overcome the upper bound of the permeability-selectivity trade-off. The simulated water transport using computational model showed evidence of the gutter effect of the MXene/CNC framework. This work offers new possibilities for utilizing a 2D materials-based hybrid framework to rationally design fit-for-purpose separation membranes.

This work demonstrates the design of a hybrid dimensional MXene/CNC framework regulated polyamide-based nanofiltration membrane capable of breaking the permeability-selectivity trade-off and achieving high rejection against emerging contaminants simultaneously.