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[Display omitted] • We for the first time synthesize crystalline CTF-1 nanoribbons (CTF-1-NR). • The width of 1D nanoribbons can be facilely tuned by varying the solvent volume. • The CTF-1-NR are intercalated with Graphene Oxide (GO) membranes to enlarge water transport. • CTF-1-NR enhance photocatalytic ability compared to 2D nanosheets counterparts. • CTF-1-NR/GO membrane allows for recoverable permeability by solar illumination. Covalent triazine frameworks (CTFs) are drawing substantial interest as porous crystalline two-dimensional (2D) or three-dimensional (3D) nanomaterials. Fabrication of CTFs nanoribbon is challenging but appealing to separation and photocatalysis. Here we for the first time report the synthesis of crystalline CTF-1 nanoribbons (CTF-1-NR) comprising 2–3 covalent triazine framework units in width through a polar solvent-induced fragmentation strategy. The width of 1D nanoribbons can be facilely tuned by varying the solvent (e.g. ethanol) volume in trifluoromethanesulfonic acid layer after trimerization of aromatic nitriles. The CTF-1-NR are intercalated with Graphene oxide (GO) membranes to extend 1H NMR transverse relaxation time (T 2) and enlarge the confined interspacing (∼8.8 Å), providing ultrafast water transport (∼60 L m-2h−1 bar−1) and high dye molecules rejection (98%). More significantly, the bridging CTF-1-NR enhances charge-carrier separation and gains superior solar-cleaning recoverable permeability (∼7 folds higher than GO). This study provides novel insight into the synthesis of crystalline COF nanoribbons and membrane separation. [ABSTRACT FROM AUTHOR]

Photo-assisted catalysis is proposed to be an effective approach to deal with the membrane fouling issue, which restricts the broad application of burgeoning 2D covalent organic frameworks (COF) membranes in sustainable separation process. In this work, a new type of [0D + 2D] composite membrane was developed via covalent triazine frameworks (CTF-1) nanosheets with built-in CdS quantum dots (QDs). The regular skeleton of 2D-CTF-1 facilitated the uniform growth of CdS QDs (3 nm) on the planar nanosheets. CdS/CTF-1 composite membrane exhibits high water flux (>170 L m−2 h−1, 0.1 MPa) and high dyes rejection (>94%) via manipulating transportation channels. More importantly, the built-in [0D + 2D]-heterojunction significantly improves the photocatalytic in - situ cleaning and disinfection performance of CdS/CTF-1 membrane, allowing for regenerating permeability (>95%) with the assist of H 2 O 2 during multiple operations. Thus, we provide a prospective strategy to resolve the membrane fouling issues and enable the practical application of 2D membranes for continuous separation. Photocatalytic in - situ cleaning CdS/CTF-1 composite membrane achieves efficient and continuous separation. [Display omitted] • We literally resolve the fouling issue of 2D COF membranes for sustainable separation. • A novel [0D + 2D] membrane was developed by embedding CdS QDs in CTF-1 nanosheets. • CdS/CTF-1 membrane shows improved permeability due to additional channels. • CdS QDs enhance the photocatalytic in - situ cleaning and disinfection performance. • CdS/CTF-1 membrane regenerates its permeability >95% via sunlight illumination. [ABSTRACT FROM AUTHOR]

Photo-assisted catalysis is proposed to be an effective approach to deal with the membrane fouling issue, which restricts the broad application of burgeoning 2D covalent organic frameworks (COF) membranes in sustainable separation process. In this work, a new type of [0D + 2D] composite membrane was developed via covalent triazine frameworks (CTF-1) nanosheets with built-in CdS quantum dots (QDs). The regular skeleton of 2D-CTF-1 facilitated the uniform growth of CdS QDs (3 nm) on the planar nanosheets. CdS/CTF-1 composite membrane exhibits high water flux (>170 L m−2 h−1, 0.1 MPa) and high dyes rejection (>94%) via manipulating transportation channels. More importantly, the built-in [0D + 2D]-heterojunction significantly improves the photocatalytic in - situ cleaning and disinfection performance of CdS/CTF-1 membrane, allowing for regenerating permeability (>95%) with the assist of H 2 O 2 during multiple operations. Thus, we provide a prospective strategy to resolve the membrane fouling issues and enable the practical application of 2D membranes for continuous separation. Photocatalytic in - situ cleaning CdS/CTF-1 composite membrane achieves efficient and continuous separation. [Display omitted] • We literally resolve the fouling issue of 2D COF membranes for sustainable separation. • A novel [0D + 2D] membrane was developed by embedding CdS QDs in CTF-1 nanosheets. • CdS/CTF-1 membrane shows improved permeability due to additional channels. • CdS QDs enhance the photocatalytic in - situ cleaning and disinfection performance. • CdS/CTF-1 membrane regenerates its permeability >95% via sunlight illumination. [ABSTRACT FROM AUTHOR]

Lamellar membranes are attracting extensive attention for high throughput and precise molecules/ions sieve separation. However, the energy-consuming exfoliation and low yield of single-layer nanosheets restrict the massive production of membranes. Herein, we facilely fabricated 2D Ni-mediated metal-organic framework (Ni-MOF) membranes directly from multiply stacked nanosheets (MSNs) for both aqueous and organic molecular sieve separation. Multiply layered nanosheets were obtained from a high concentration dispersion via simple ultrasonic treatment. The morphology and chemistry of synthesized Ni-MOF nanosheets were characterized via scanning electron microscopy (SEM), N 2 adsorption-desorption, Fourier transform infrared spectra (FTIR), and X-ray photoelectron spectra (XPS). The thickness of Ni-MOF membranes could be well regulated by the volume of dispersion. The membrane exhibited high molecular rejection to 8GX (97.29%), EB (96.28%), CR (99.69%), and CBB (93.31%) in water, respectively and a stable perm-selectivity in continuous 24 h filtration. The lamellar membrane showed excellent pressure and pH (2–10) resistance. The membrane achieved rational permeance of various organic solvents mainly depending on viscosity and good rejection to MB (91.37%), BY (92.01%), and EB (96.90%) in isopropanol. Ni-MOF membranes directly prepared by multiply stacked nanosheets (MSNs) and exhibited a stable aqueous/organic molecular sieve separation. [Display omitted] • 2D Ni-mediated metal-organic framework (Ni-MOF) membranes were fabricated directly from multiply stacked nanosheets (MSNs). • Ni-MOF membrane exhibited high molecular rejection in water or organic solvent. • Ni-MOF membrane showed excellent pressure and pH (2–10) resistance. [ABSTRACT FROM AUTHOR]