Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COF...Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COFs) with intrinsically high porosity, controllable pore size, uniform pore size distribution and long-range ordered channel structure, have emerged as next-generation materials to fabricate advanced separation membranes. This feature article summarizes some latest studies in the development of pure COF membranes in our lab, including their fabrication and applications in chemical separations. Finally, current challenges facing high-performance COF separation membranes are discussed.展开更多
To date,significant efforts have been devoted to eliminating hazardous components to purify wastewater through the development of various nanomaterials.Covalent organic frameworks(COFs),an important branch of the poro...To date,significant efforts have been devoted to eliminating hazardous components to purify wastewater through the development of various nanomaterials.Covalent organic frameworks(COFs),an important branch of the porous crystalline family,possess the peculiarity of ultrahigh surface area,adjustable pore size,and facile functionality.Exciting studies from design fabrication to potential applications in water treatment by COF-based membranes(COMs)have emerged.This review summarizes various preparation strategies and synthesis mechanisms for COMs,including layer-by-layer stacking,in situ growth,interfacial polymerization,and electrochemical synthesis,and briefly describes the advanced characterization techniques for COMs.Moreover,the application of COMs in heavy metal removal,dye separation,purification of radionuclides,pollutant detection,sea water desalination,and so on,is described and discussed.Finally,the perspectives on future opportunities for designing COMs in water purification have been proposed.展开更多
Aqueous two-phase system features with ultralow interfacial tension and thick interfacial region,affording unique confined space for membrane assembly.Here,for the first time,an aqueous two-phase interfacial assembly ...Aqueous two-phase system features with ultralow interfacial tension and thick interfacial region,affording unique confined space for membrane assembly.Here,for the first time,an aqueous two-phase interfacial assembly method is proposed to fabricate covalent organic framework(COF)membranes.The aqueous solution containing polyethylene glycol and dextran undergoes segregated phase separation into two water-rich phases.By respectively distributing aldehyde and amine monomers into two aqueous phases,a series of COF membranes are fabricated at water-water interface.The resultant membranes exhibit high NaCl rejection of 93.0-93.6% and water permeance reaching 1.7-3.7 L m^(−2) h^(−1) bar^(−1),superior to most water desalination membranes.Interestingly,the interfacial tension is found to have pronounced effect on membrane structures.The appropriate interfacial tension range(0.1-1.0 mN m^(−1))leads to the tight and intact COF membranes.Furthermore,the method is extended to the fabrication of other COF and metal-organic polymer membranes.This work is the first exploitation of fabricating membranes in all-aqueous system,confering a green and generic method for advanced membrane manufacturing.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 22378300 and 21878215)National Key Research and Development Program of China (No.2022YFB3805202)+3 种基金Key Research and Development Program of Zhejiang Province (No. 2021C03173)Ningbo Key Research and Development Project (No. 2022Z121)Program of Introducing Talents of Discipline to Universities (No.BP0618007)Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COFs) with intrinsically high porosity, controllable pore size, uniform pore size distribution and long-range ordered channel structure, have emerged as next-generation materials to fabricate advanced separation membranes. This feature article summarizes some latest studies in the development of pure COF membranes in our lab, including their fabrication and applications in chemical separations. Finally, current challenges facing high-performance COF separation membranes are discussed.
基金supported by National Key Research and Development Program of China(2018YFC1900105)National Natural Science Foundation of China(22276054)Beijing Outstanding Young Scientist Program.
文摘To date,significant efforts have been devoted to eliminating hazardous components to purify wastewater through the development of various nanomaterials.Covalent organic frameworks(COFs),an important branch of the porous crystalline family,possess the peculiarity of ultrahigh surface area,adjustable pore size,and facile functionality.Exciting studies from design fabrication to potential applications in water treatment by COF-based membranes(COMs)have emerged.This review summarizes various preparation strategies and synthesis mechanisms for COMs,including layer-by-layer stacking,in situ growth,interfacial polymerization,and electrochemical synthesis,and briefly describes the advanced characterization techniques for COMs.Moreover,the application of COMs in heavy metal removal,dye separation,purification of radionuclides,pollutant detection,sea water desalination,and so on,is described and discussed.Finally,the perspectives on future opportunities for designing COMs in water purification have been proposed.
基金The authors gratefully acknowledge financial support from National Key Research and Development Program of China(Nos.2021YFC2101200 and 2021YFB3802200)National Natural Science Foundation of China(Nos.22178251,21878216,91934302,21838008 and 21878215)+1 种基金Program of Introducing Talents of Discipline to Universities(No.BP0618007)the Haihe Laboratory of Sustainable Chemical Transformations.
文摘Aqueous two-phase system features with ultralow interfacial tension and thick interfacial region,affording unique confined space for membrane assembly.Here,for the first time,an aqueous two-phase interfacial assembly method is proposed to fabricate covalent organic framework(COF)membranes.The aqueous solution containing polyethylene glycol and dextran undergoes segregated phase separation into two water-rich phases.By respectively distributing aldehyde and amine monomers into two aqueous phases,a series of COF membranes are fabricated at water-water interface.The resultant membranes exhibit high NaCl rejection of 93.0-93.6% and water permeance reaching 1.7-3.7 L m^(−2) h^(−1) bar^(−1),superior to most water desalination membranes.Interestingly,the interfacial tension is found to have pronounced effect on membrane structures.The appropriate interfacial tension range(0.1-1.0 mN m^(−1))leads to the tight and intact COF membranes.Furthermore,the method is extended to the fabrication of other COF and metal-organic polymer membranes.This work is the first exploitation of fabricating membranes in all-aqueous system,confering a green and generic method for advanced membrane manufacturing.
