Engineering cyclodextrin-embedded polyester networks into interlayers of Ti3C2Tx MXene membranes for efficient desalination

MXene-based membranes have emerged as promising candidates for seawater desalination due to their unique two-dimensional (2D) lamellar structures, excellent hydrophilicity, and tunable interlayer spacing. However, challenges such as poor salt rejection, and structural instability hinder their broader application. Herein, we present novel Ti 3 C 2 T x MXene membranes owing cyclodextrin (CD)-embedded polyester network between their interlayers through trimesoyl chloride (TMC)-induced interfacial crosslinking, which not only promotes the formation of stable cross-links between the layers of the MXene nanosheets but also enhances their desalination performance. Various characterization methods were used to demonstrate the successful preparation of the Ti 3 C 2 T x MXene-based membranes cross-linked with the specific polyester networks. Using the same dosage of CDs, the membranes modified with α-CD, β-CD and γ-CD were comparatively investigated. The membrane embedded with 5 mg of α-CD exhibited the optimal desalination performance with rejection of 93.96 %, 93.00 %, 85.88 % and 76.25 % for MgSO 4 , Na 2 SO 4 , MgCl 2 , and NaCl, respectively, and water permeabilities ranging from 93.00 to 149.06 L·m −2 ·h −1 ·bar −1 . Moreover, the Na + and Mg 2+ transport mechanisms within the prepared membrane nano-channels were further investigated by molecular dynamics (MD) simulations. This work offers an innovative approach by introducing CD/TMC interfacial crosslinking to 2D lamellar-structured membranes, providing a high-performance solution for desalination.