Introducing solar energy into membrane filtration to decrease energy and chemicals consumption represents a promising direction in membrane fields. In this study, a kind of 0D/2D heterojunction is fabricated by depositing biomineralized titanium dioxide (TiO2) nanoparticles with delaminated graphitic carbon nitride (g‐C3N4) nanosheets, and subsequently a kind of 2D heterostructure membrane is fabricated via intercalating g‐C3N4@TiO2 heterojunctions into adjacent graphene oxide (GO) nanosheets by a vacuum‐assisted self‐assembly process. Due to the enlarged interlayer spacing of GO nanosheets, the initial permeation flux of GO/g‐C3N4@TiO2 membrane reaches to 4536 Lm−2 h−1 bar−1, which is more than 40‐fold of GO membranes (101 Lm−2 h−1 bar−1) when utilized for oil/water separation. To solve the sharp permeation flux decline, arising from the adsorption of oil droplets, the a sunlight‐driven self‐cleaning process is followed, maintaining a flux recovery ratio of more than 95% after ten cycles of filtration experiment. The high permeation flux and excellent sunlight‐driven flux recovery of these heterostructure membranes manifest their attractive potential application in water purification.

Covalent organic framework (COF) membranes hold potential for widespread applicability,b ut scalable fabrication is challenging.H ere,w ed emonstrate the disorderto-order transformation from amorphous polymeric membrane to crystalline COF membrane via monomer exchange. Solution processing is used to prepare amorphous membrane and the replacing monomer is selected based on the chemical and thermodynamical stability of the final framework. Reversible imine bonds allowt he extraneous monomers to replace the pristine monomers within amorphous membrane,d riving the transformation from disordered network to ordered framework. Incorporation of intramolecular hydrogen bonds enables the crystalline COF to imprint the amorphous membrane morphology.T he COF membranes harvest proton conductivity up to 0.53 Scm À1 at 80 8 8C. Our strategy bridges amorphous polymeric and crystalline COF membranes for large-scale fabrication of COF membranes and affords guidance on materials processing.

Ionic covalent organic framework membranes (iCOFMs) hold great promise in ion conduction-relevant applications because the high content and monodispersed ionic groups could afford superior ion conduction. The key to push the upper limit of ion conductivity is to maximize the ion exchange capacity (IEC). Here, we explore iCOFMs with a superhigh ion exchange capacity of 4.6 mmol g−1, using a dual-activation interfacial polymerization strategy. Fukui function is employed as a descriptor of monomer reactivity. We use Brønsted acid to activate aldehyde monomers in organic phase and Brønsted base to activate ionic amine monomers in water phase. After the dual-activation, the reaction between aldehyde monomer and amine monomer at the water-organic interface is significantly accelerated, leading to iCOFMs with high crystallinity. The resultant iCOFMs display a prominent proton conductivity up to 0.66 S cm−1, holding great promise in ion transport and ionic separation applications.