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The design and synthesis of covalent organic frameworks (COFs) with high chemical stability pose significant challenges for practical applications. Although a growing number of robust COFs have been developed and employed for a broad scope of applications, the assessment of COF stability has primarily relied on qualitative descriptions, lacking a rational and quantitative assessment. Herein, a novel assessment method is presented that enables visual and quantitative depiction of COF stability. By analyzing the PXRD patterns of chemically stable β‐ketoenamine‐based COFs (KEA‐COFs), two crystallinity‐dependent parameters are identified, the relative intensity (I2θrel) and the relative area (A2θrel) of the main peak (2θ), which are expected to establish a standardized criterion for assessing COF crystallinity. Based on these parameters, the crystalline changes after stability tests can be visually presented, which provides a rational and quantitative assessment of their stability. This study not only demonstrates the remarkable chemical stability of KEA‐COFs, but also provides valuable insights into the quantitative evaluation of COFs' crystallinity and stability. [ABSTRACT FROM AUTHOR]

Three‐dimensional covalent organic frameworks (3D COFs) with spatially periodic networks demonstrate significant advantages over their 2D counterparts, including enhanced specific surface areas, interconnected channels, and more sufficiently exposed active sites. Nevertheless, research on these materials has met an impasse due to serious problems in crystallization and stability, which must be solved for practical applications. In this Minireview, we first summarize some strategies for preparing functional 3D COFs, including crystallization techniques and functionalization methods. Hereafter, applications of these functional materials are presented, covering adsorption, separation, catalysis, fluorescence, sensing, and batteries. Finally, the future challenges and perspectives for the development of 3D COFs are discussed. [ABSTRACT FROM AUTHOR]

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 m2 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. [ABSTRACT FROM AUTHOR]

The modification of covalent organic frameworks (COFs) based on postsynthetic covalent linkages is discussed in this review. In this strategy, the COF is preparedas scaffold and then assembled with functional groups with preservation of structural skeleton. Recent studies indicate that a number of COFs, such as COF‐5 and 3D‐OH‐COOF, are controllable to postsynthetic modification. Furthermore, covalentmodifications including triazole, ester, amide, sulfide, o‐carbamate, ether, and oxime are suitable for postsynthetic functionalization. The rapid development of postsynthetic modification demonstrates that this approach will provide a general platform to create COFs as robust functional porous materials for wide applications. [ABSTRACT FROM AUTHOR]

A new 3-D inorganic–organic hybrid framework microporous material Zn3(bbdc)3(4,4′-bpy)·2(DMF)·4(H2O) (1), which is constructed by coordination of zinc ions with 4,4′-bibenzene-dicarboxylic acid (H2bbdc) and 4,4′-bipyridine (4,4′-bpy), was obtained at mild synthesis condition. Crystallographic data for the compound (1), C58H54N4O18Zn3, orthorhombic, space group Pbcn, a=14. 532(3) A˚, b=25.037(5) A˚, c=18.184(4) A˚, Z=4, V=6616(2) A˚3. [Copyright &y& Elsevier]