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Three‐dimensional covalent organic frameworks (3D COFs) have gained increasing attention for their attractive features. However, the development of 3D COFs is strongly restricted, mainly due to their synthetic difficulty and complicated structure determination. Post‐synthetic modification, which can avoid these problems by incorporating functional moieties into a predetermined framework, provides an alternative way to construct 3D COFs with specific functions. Herein, we report the designed synthesis and characterization of a series of highly crystalline 3D COFs with different loadings of ethynyl groups. Notably, these alkyne‐tagged 3D COFs provide a platform for targeted anchoring various specific groups onto the pore walls via click reactions. Moreover, the pore surface engineering can accordingly change their properties, for example, the obtained click products exhibited higher CO2/N2 selectivity. We describe a simple but powerful strategy to build functional 3D COFs, which will certainly advance them for a ranging of interesting applications in the future. [ABSTRACT FROM AUTHOR]

A novel zinc vanadate (NH4)4[Zn5VIV4VV16O56H2(H2O)4] was synthesized by the hydrothermal method and a zinc–vanadium–water system without any organic media was studied for the first time. The pH and the reaction time play important roles in the formation of the final products and the structure-change of the different products was also discussed. The new phase (NH4)4[Zn5VIV4VV16O56H2(H2O)4] is a three-dimensional structure with a novel V5O14 layer connected by ZnO4 and ZnO6 polyhedra. The V5O14 layer in (NH4)4[Zn5VIV4VV16O56H2(H2O)4] was constructed with four distorted VO5 square pyramids and one regular VO4 triangular pyramid which is different from the reported ones due to the pure inorganic mild synthesis conditions. [ABSTRACT FROM AUTHOR]

Stable extra-large-pore zeolites are desirable for industrial purposes due to their ability to accommodate bulky reactants and diffusion through channels. Although there are several extra-large pore zeolites reported, stable ones are rare. Thus, their stabilization is a feasible strategy for industrial applications. Here, an extra-large-pore zeolite EWT with boron substitution is presented, and the resulting zeolite B-RZM-3 increased the thermal stability from 600 °C in its silica form to 850 °C. The crystal structure, determined by combining continuous rotation electron diffraction (cRED) and powder X-ray diffraction (PXRD), shows that B atoms preferentially substitute the interrupted (HO)T(OT) 3 (Q 3 ) sites and are partially converted into 3-coordination to relax framework deformation upon heating. After Al-reinsertion post-treatment, Al-B-RZM-3 shows higher ethylbenzene selectivity and ethylene conversion rate per mol acid site than commercial ZSM-5 and Beta zeolite in benzene alkylation reaction. Synthesizing extra-large-pore zeolite in borosilicate form is a potential approach to stabilize interrupted zeolites for commercial applications., (© 2022 Wiley-VCH GmbH.)

The development of novel zeolite-like materials with large channel windows and high stability is of importance but remains a tremendous challenge. Herein, we report the first example of a 3D covalent organic framework with zeolitic network, namely the zeolitic organic framework (ZOF). By combining two kinds of tetrahedral building blocks with fixed or relatively free bond angles, ZOF-1 with the zeolitic crb net has been successfully synthesized. Its structure was determined by the single-crystal 3D electron diffraction technique. Remarkably, ZOF-1 shows high chemical stability, large pore size (up to 16 Å), and excellent specific surface area (≈2785 m 2  g -1 ), which is superior to its analogues with the same network, including traditional aluminosilicate zeolites and zeolitic imidazole frameworks. This study thus opens a new avenue to construct zeolite-like materials with pure organic frameworks and will promote their potential applications in adsorption and catalysis for macromolecules., (© 2022 Wiley-VCH GmbH.)

Three-dimensional covalent organic frameworks (3D COFs) have gained increasing attention for their attractive features. However, the development of 3D COFs is strongly restricted, mainly due to their synthetic difficulty and complicated structure determination. Post-synthetic modification, which can avoid these problems by incorporating functional moieties into a predetermined framework, provides an alternative way to construct 3D COFs with specific functions. Herein, we report the designed synthesis and characterization of a series of highly crystalline 3D COFs with different loadings of ethynyl groups. Notably, these alkyne-tagged 3D COFs provide a platform for targeted anchoring various specific groups onto the pore walls via click reactions. Moreover, the pore surface engineering can accordingly change their properties, for example, the obtained click products exhibited higher CO 2 /N 2 selectivity. We describe a simple but powerful strategy to build functional 3D COFs, which will certainly advance them for a ranging of interesting applications in the future., (© 2021 Wiley-VCH GmbH.)

A novel zinc vanadate (NH4)4[Zn5VIV4VV16O56H2(H2O)4] was synthesized by the hydrothermal method and a zinc-vanadium-water system without any organic media was studied for the first time. The pH and the reaction time play important roles in the formation of the final products and the structure-change of the different products was also discussed. The new phase (NH4)4[Zn5VIV4VV16O56H2(H2O)4] is a three-dimensional structure with a novel V5O14 layer connected by ZnO4 and ZnO6 polyhedra. The V5O14 layer in (NH4)4[Zn5VIV4VV16O56H2(H2O)4] was constructed with four distorted VO5 square pyramids and one regular VO4 triangular pyramid which is different from the reported ones due to the pure inorganic mild synthesis conditions.