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Membrane separation has become an indispensable separation technology in social production, playing an important role in drug production, mineral exploitation, water purification, etc. The key core of membranes lies in achieving efficient and precise sieving between substances. As a result, a typical trade‐off arises: highly permeable membranes usually sacrifice selectivity and vice versa. To address this dilemma, long‐term research has focused on comprehensive understanding and modelling of synthetic membranes at various scales. A significant advancement in this arena is the advent of three‐dimensional covalent organic framework (3D COF) membranes, a novel category of long‐range ordered porous organic polymer materials. Characterized by an abundance of interconnected channels, diverse pore wall properties, tunable structures, and robust thermal and chemical resilience, 3D COF membranes offer a promising approach for efficient substance separation. This review undertakes a meticulous investigation of the synthesis and physicochemical properties of 3D COF membranes, accentuating the underlying design principles, fabrication methods, and application attempts. A comprehensive assessment of their research trajectory and current standing in the field of membrane processes is provided. The review culminates in a forward‐looking outlook, summarizing future research directions and highlighting the substantial potential of this innovative work to shape the future of efficient membrane separation processes. [ABSTRACT FROM AUTHOR]

Membranes are important in the pharmaceutical industry for the separation of antibiotics and salts. However, its widespread adoption has been hindered by limited control of the membrane microstructure (pore architecture and free‐volume elements), separation threshold, scalability, and operational stability. In this study, 4,4′,4′′,4′′′‐methanetetrayltetrakis(benzene‐1,2‐diamine) (MTLB) as prepared as a molecular building block for fabricating thin‐film composite membranes (TFCMs) via interfacial polymerization. The relatively large molecular size and rigid molecular structure of MTLB, along with its non‐coplanar and distorted conformation, produced thin and defect‐free selective layers (~27 nm) with ideal microporosities for antibiotic desalination. These structural advantages yielded an unprecedented high performance with a water permeance of 45.2 L m−2 h−1 bar−1 and efficient antibiotic desalination (NaCl/adriamycin selectivity of 422). We demonstrated the feasibility of the industrial scaling of the membrane into a spiral‐wound module (with an effective area of 2.0 m2). This module exhibited long‐term stability and performance that surpassed those of state‐of‐the‐art membranes used for antibiotic desalination. This study provides a scientific reference for the development of high‐performance TFCMs for water purification and desalination in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) membranes featuring uniform topological structures and devisable functions, show huge potential in water purification and molecular separation. Nevertheless, the inability of uniform COF membranes to be produced on an industrial scale and their nonenvironmentally friendly fabrication method are the bottleneck preventing their industrial applications. Herein, we report a new green and industrially adaptable scraping‐assisted interfacial polymerization (SAIP) technique to fabricate scalable and uniform TpPa COF membranes. The process used non‐toxic and low‐volatility ionic liquids (ILs) as organic phase instead of conventional organic solvents for interfacial synthesis of TpPa COF layer on a support membrane, which can simultaneously achieve the purposes of (i) improving the greenness of membrane‐forming process and (ii) fabricating a robust membrane that can function beyond the conventional membranes. This approach yields a large‐area, continuous COF membrane (19×25 cm2) with a thickness of 78 nm within a brief period of 2 minutes. The resulting membrane exhibited an unprecedented combination of high permeance (48.09 L m−2 h−1 bar−1) and antibiotic desalination efficiency (e.g., NaCl/adriamycin separation factor of 41.8), which is superior to the commercial benchmarking membranes. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation technology stands out as a promising solution for sustainable freshwater production. To achieve sustained and efficient water evaporation, it is crucial to carefully modulate the distribution of water content within the solar evaporator. In this study, a novel light-temperature responsive composite hydrogel-based solar evaporator was successful constructed. This involved the incorporation of a hydrophilic backbone (polyacrylamide) and a highly efficient solar absorber (multi-walled carbon nanotubes) into a temperature-sensitive hydrogel polymer backbone (poly (N, N-diethylacrylamide)). Due to its low critical solution temperature, the evaporator can undergo a hydrophilic/hydrophobic phase transition alternating day and night conditions. In natural sunlight, the upper hydrogel evaporation region is rendered hydrophobic, minimizing heat loss and preventing salt crystallization. Simultaneously, the bottom water delivery region is hydrophilic to ensure sufficient water supply. At night, the evaporator absorbs water and dissolves, thereby facilitating the rapid return of highly concentrated brine. Leveraging the spontaneously formed Janus structure, the photo-hydrothermal hydrogel achieves an impressive evaporation rate of 2.74 kg m−2 h−1 and exhibits excellent salt resistance. The notable water evaporation performance and robust salt resistance provide exciting possibilities for achieving ultrafast solar water purification. [Display omitted] • A photothermo-responsive hydrogel solar evaporator was developed, exhibiting high evaporation rates and salt resistance. • In natural sunlight, the hydrogel autonomously generates a Janus structure through inherent light-temperature responsive. • At night, the evaporator absorbs water and dissolves, facilitating the rapid return of highly concentrated brine. [ABSTRACT FROM AUTHOR]