Exploring the potential of MXene nanoslit for water desalination through molecular dynamics simulations

The charge features of nanoslit were deemed to exert significant influences on optimization of its desalination performance. The MXene nanoslit carries richness of charge features, thus it should possess exceptional desalination performance. However, the optimal application conditions of MXene nanoslit as a water desalination membrane has not been systematically explored. In this work, we adopted molecular dynamics (MD) methods to assess the desalination performance of Ti₃C₂T_X nanoslits. The influence factors, including the termination group, the slit width, temperature, pressure, and thickness were discussed with the expectation of probing the optimal application conditions for MXene nanoslit membranes. Simulation results showed that MXene nanoslit possesses excellent desalination performance thanks to the charge features of the nanoslit channel. The increase of slit width, temperature, and pressure all promote the water permeance but deteriorate the ion rejection performance. Fortunately, the tradeoff between water permanence and ion rejection rate can be mediated by the termination groups. The increase of MXene layer number could effectively improve the desalination performance, taking both water flux and ion rejection performance into account. The present work might provide some valuable suggestions for the design of water desalination membranes with exceptional desalination performance by manipulating the electrostatic properties of membranes. © 2023 Elsevier B.V.