Two-dimensional multilayer materials-enabled precise molecular sieving membranes for water purification

The growth and urbanization of global population have intensified water resource challenges as well as increasing contamination. Membrane separation technology has effectively tackled issues such as drinking water purification, wastewater treatment, and seawater desalination. Recently, two-dimensional (2D) materials have emerged as promising candidates for enhancing the efficiency of water purification. These materials enable rapid advancements in traditional membrane technologies by leveraging their unique nanoscale properties and ease of surface modification, facilitating the creation of multifunctional membranes with superior performance. Extensive research has focused on 2D materials like graphene and similar substances for developing nanoporous and layered membranes. This review highlights significant progress in optimizing transport pathways by addressing defects, pores, and edges in nanosheets, as well as interactions within layers. The impact of intrinsic structural features on membrane functionality was examined. Specifically, this paper discussed the precise control of molecular sieving by various porous 2D multilayer materials, including graphene oxide (GO), MXene (T_i3C₂T_x), transition metal disulfide compounds (TMDC), boron nitride (BN) and graphitized carbonitride (g-C₃N₄). The analysis covers membrane morphology, water purification mechanism and the development of transport routes. In addition, the application of stable films and emphasize their role in the commercialization of two-dimensional multilayer membranes were also discussed. This review emphasizes the revolutionary potential of two-dimensional materials in water purification, and outlines the key factors needed for the transition from research to commercial application.