From the Rise of 2D Nanomaterials to High-Performance Separation Membranes: A Critical Review

Membrane-based nanotechnology is emerging as a powerful tool for efficient and sustainable liquid separations, particularly in water desalination. Traditional membranes have driven this growth due to their energy efficiency and compact size. However, they often face a trade-off between permeability and selectivity. This limitation is propelling research toward next-generation membranes with superior performance. Two promising classes are porous nanosheets and laminar membranes. These can be constructed from a variety of two-dimensional (2D) nanomaterials, including graphene and its derivatives, metal–organic frameworks, transition-metal dichalcogenides, covalent-organic frameworks, and MXenes. The exceptional versatility in structure, pore size, and chemical functionality of these materials allows for precise tuning, leading to superior permeability and selectivity compared to those of traditional membranes. In this review, we focused on the transport mechanisms governing separations in both porous and laminar membranes fabricated from 2D nanomaterials, consolidating existing insights into the synthesis and modeling of these membranes for separation applications. By investigating the capabilities of each material in both membrane configurations, we identify and highlight avenues for future research and innovation, paving the way for enhanced advancements and optimization strategies in the separation process.