Progress in covalent organic framework membranes for water desalination: Mechanistic insights, synthesis strategies, applications, and future prospects

Membrane-based desalination has become a crucial technology, harnessing the efficiency and scalability of membrane systems to address global water scarcity. Covalent organic frameworks (COFs), with their precisely engineered nanopores and customizable chemical functionalities, show great potential for advancing next-generation desalination membranes. This review begins by exploring the fundamental separation mechanisms in COF-based desalination, including size exclusion, surface wettability modulation, and electrostatic interactions. It then highlights recent advances in the design and synthesis of COF membranes, with a focus on innovations in structural control and interfacial engineering. The application of COF membranes in desalination is categorized based on driving forces: pressure-driven desalination, thermally driven distillation, vapor pressure-driven processes, and electrically driven separation. Looking to the future, key research areas are identified, including machine learning-guided pore optimization, multifunctional COF hybrid architectures, and large-scale performance validation to move from laboratory breakthroughs to real-world implementation. By synthesizing these insights, this review aims to promote interdisciplinary collaboration that can unlock the full potential of COFs in creating energy-efficient, durable, and sustainable desalination technologies.