Owing to its 100% theoretical salt rejection capability, membrane distillation (MD) has emerged as a promising seawater desalination approach to address freshwater scarcity. Ideal MD requires high vapor permeate flux established by cross-membrane temperature gradient (∆T) and excellent membrane durability. However, it’s difficult to maintain constant ∆T owing to inherent heat loss at feedwater side resulting from continuous water-to-vapor transition and prevent wetting transition-induced membrane fouling and scaling. Here, we develop a Ti₃C₂T_x MXene-engineered membrane that imparts efficient localized photothermal effect and strong water-repellency, achieving significant boost in freshwater production rate and stability. In addition to photothermal effect that circumvents heat loss, high electrically conductive Ti₃C₂T_x MXene also allows for self-assembly of uniform hierarchical polymeric nanospheres on its surface via electrostatic spraying, transforming intrinsic hydrophilicity into superhydrophobicity. This interfacial engineering renders energy-efficient and hypersaline-stable photothermal membrane distillation with a high water production rate under one sun irradiation.

由于其 100% 的理论脱盐能力，膜蒸馏 (MD) 已成为解决淡水短缺问题的一种很有前途的海水淡化方法。理想的 MD 需要通过跨膜温度梯度 (ΔT) 建立的高蒸汽渗透通量和出色的膜耐久性。然而，由于持续的水-气相转变导致给水侧固有的热损失，很难保持恒定的 ΔT，并防止润湿转变引起的膜污染和结垢。在这里，我们开发了 Ti ₃ C ₂ T _xMXene 工程膜具有高效的局部光热效应和强大的防水性，显着提高淡水生产率和稳定性。除了避免热损失的光热效应外，高导电性 Ti ₃ C ₂ T _x MXene 还允许通过静电喷涂在其表面自组装均匀的多级聚合物纳米球，将固有亲水性转化为超疏水性。这种界面工程使节能和高盐度稳定的光热膜蒸馏在一次太阳照射下具有高产水率。