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Comprehensive Summary: This review presents a comprehensive examination of fully conjugated covalent organic frameworks (COFs), which constitute an emerging class of porous materials with immense potential for diverse applications. This article focuses on diversified fully conjugated COFs, including sp2 carbon‐carbon linkages, pyrazine linkages, benzobisoxazole linkages, dioxin linkages, β‐aminoalkenone linkages, etc. The synthesis techniques and structural attributes of these COFs are expounded upon in great detail, along with their potential applications in various fields. The review thus provides a valuable resource for researchers keen on delving into the synthesis and applications of fully conjugated COFs, thereby highlighting their potential for developing novel functional materials with distinctive properties. [ABSTRACT FROM AUTHOR]

A weak CH/O hydrogen‐bonded organic framework (HOF) with both rigidity and flexibility that could easily and reversibly switch from a non‐crystalline to a crystalline phase was constructed. The specific solvent molecule acts as a "key" to control the crystallinity, while the highly rigid triangle macrocycle as the building block is the "lock". The introduction and removal of the "key" could influence the local flexibility of the whole framework and lead to switchable crystallinity. Furthermore, the obtained HOF exhibits excellent separation efficiency for benzene and cyclohexane (94.4 %). [ABSTRACT FROM AUTHOR]

Color‐cognitive detection plays an important role in many developing applications such as optical sensing, high‐solution imaging, wearable biometric monitoring, and human visual cognitive system. Although color‐cognitive devices have been demonstrated, the large size, complex manufacturing, high cost, and non‐flexible processing impede their applications for distinguishing color information. Herein, gradient bandgap‐tunable perovskite microwire arrays with excellent crystallinity and pure crystallographic orientation are realized by the synergy of the capillary‐bridge assembly method and mild component engineering processing, yielding high‐performance integrated color‐cognitive devices with the spectral resolution of 14 nm ranging from 405 nm to 760 nm, responsivities over 103 A W−1, and detectivities over 1015 Jones. Furthermore, the integrated flexible color‐cognitive devices are demonstrated for accurately recognizing similar colors, which can be applied in color blindness correction. The efficient color recognition performances, together with the flexible processing, open new opportunities for the on‐chip integration of wearable devices based on microwire arrays. [ABSTRACT FROM AUTHOR]

We report a facile strategy to prepare a large amount of ultrathin graphdiyne (GDY) with good crystallinity in the mixture of oil–water systems. By simply mixing the solution of GDY monomer in CHCl3 and the copper acetate solution as a catalyst in water and stirring at room temperature, ultrathin GDY films with a thickness of ∼4 nm were obtained in a yield of 95 %. This work provides a feasible path for the substantial preparation of GDY films and may pave the way to the development of substantial preparation of the GDY materials. [ABSTRACT FROM AUTHOR]

The realization of polarized photodetection vigorously accelerates the development of applications in quantum communication, medicine, imaging, and sensing. Polarized light detection has been realized based on chiral perovskites, but the high concentrations of toxic lead and instability in those reported perovskites impose difficulties for their commercial applications. Furthermore, the precise patterning of perovskite arrays with high crystallinity is in high demand for the integration of optoelectronic devices. Herein, pure (001)‐orientated lead‐free chiral 2D double perovskite single‐crystalline microwire arrays are fabricated by the capillary‐bridge confined assembly technique. Perovskite microwire arrays present remarkable environmental stability under ambient conditions. With the synergy of the excellent crystallinity and sensitive circular‐polarization absorption of chiral perovskite microwire arrays, outstanding circularly polarized light photodetectors are realized, with responsivity exceeding 52 mA W−1 and detectivity exceeding 3.9 × 1011 Jones. [ABSTRACT FROM AUTHOR]

The BiVO4/HNTs hybrid photocatalysts were synthesized by liquid phase precipitation using natural halloysite nanotubes (HNTs) as supporter and Bi(NO3)·5H2O as resource of Bi. XRD, scanning electron microscopy (SEM), transmission electron microscopy, HRTEM, x-ray photo electron spectroscopy and UV–Vis DRS were used to characterize the samples prepared at different calcination temperatures, and the effects of crystallization, Brunauer–Emmett–Teller specific surface area and morphological structure on the photoactivity were investigated. Results reveal that increasing calcination temperature can accelerate the transition of BiVO4 from tetragonal to monoclinic and also decrease the surface area of BiVO4/HNTs. The SEM results showed that BiVO4 was successfully coated on HNTs surface with ellipsoid or near rod like morphology, and the obtained BiVO4/HNTs had regular nanotube morphology. HRTEM results showed that, the regular fringe spacing of the lattice planes are about 0.474 and 0.364 nm, which is consistent with the (110) and (200) plane of the monoclinic and tetragonal BiVO4, confirming the exiting of mixed crystal structure in BiVO4/HNTs. BiVO4 with tetragonal phase (80.02%) and monoclinic phase (19.98%) mixed crystal is loaded on the surface of HNTs with calcinations at 400 °C for 2 h. The structure and Si (Al)–O bond of HNTs can be obviously changed over the calcination temperature of 400 °C. The effect of calcination temperature on photocatalytic reactivity of samples was investigated by degradation of dyes (MB, MO and RhB) under simulated solar light. And the sample calcined at 400 °C with the better mixed crystalline structure and larger specific surface area exhibits significant activity with the removal rate of MB and RhB up to 100% within 4 h. The degradation of MB follows the first order kinetic model. BiVO4/HNTs photocatalysts with the band gap of 2.34 eV has higher photocatalytic reaction rate and better sedimentation performance than Degussa P25. The photocatalytic degradation efficiency of BiVO4/HNTs for MB was no significant reduction after four times recycles. [ABSTRACT FROM AUTHOR]

Graphdiyne (GDY), as a new carbon allotrope, possessing both sp‐ and sp2‐hybridized carbon atoms, has attracted extensive attention due to great application potentials in various fields. To realize a fundamental understanding of the intrinsic properties of GDY, the controllable synthesis of ultrathin and highly crystalline GDY is necessary and challenging. Herein, a confined interfacial synthetic strategy towards highly crystalline ultrathin GDY at the water/oil/organogel interface, with greatly improved control over GDY structures, is reported. The morphology and chemical composition of GDY was characterized accordingly. After loading with gold, the as‐prepared hydrophobic Au/GDY system showed excellent performance in the nitrogen reduction reaction, reaching the highest yield of 4.15 μg cm−2 h−1 with a Faraday efficiency of 1.95 %. [ABSTRACT FROM AUTHOR]

Crystalline Porous Materials, Hydrogen-Bonded Organic Framework, Local Flexibility, Porous Molecular Crystals, Switchable Crystallinity Inside Back Cover: Rigid-Flexible Hybrid Porous Molecular Crystals with Guest-Induced Reversible Crystallinity (Angew. Keywords: Crystalline Porous Materials; Hydrogen-Bonded Organic Framework; Local Flexibility; Porous Molecular Crystals; Switchable Crystallinity EN Crystalline Porous Materials Hydrogen-Bonded Organic Framework Local Flexibility Porous Molecular Crystals Switchable Crystallinity 1 1 1 03/15/23 20230320 NES 230320 B A rigid-flexible b hybrid hydrogen-bonded organic framework (HOF) with guest-induced reversible crystallinity was designed by Yingjie Zhao and Danbo Wang in their Research Article (e202217903). [Extracted from the article]

Keywords: Crystalline Porous Materials; Hydrogen-Bonded Organic Framework; Local Flexibility; Porous Molecular Crystals; Switchable Crystallinity EN Crystalline Porous Materials Hydrogen-Bonded Organic Framework Local Flexibility Porous Molecular Crystals Switchable Crystallinity 1 1 1 03/15/23 20230320 NES 230320 B A rigid-flexible b hybrid hydrogen-bonded organic framework (HOF) with guest-induced reversible crystallinity was designed by Yingjie Zhao and Danbo Wang in their Research Article (e202217903). A specific compound, such as hexane, acts as a "key" to control the crystallinity, while the triangle macrocycle as the building module is the "lock". Crystalline Porous Materials, Hydrogen-Bonded Organic Framework, Local Flexibility, Porous Molecular Crystals, Switchable Crystallinity. [Extracted from the article]

Keywords: crystallinity; electrochemistry; graphdiyne; interfaces; thin films EN crystallinity electrochemistry graphdiyne interfaces thin films 7732 7732 1 06/25/20 20200623 NES 200623 B Fabrication of ultrathin b and highly crystalline GDY film is of vital importance for studies of their intrinsic properties. This work reports the successful application of a liquid/liquid/gel system for confined synthesis of GDY film with high quality in a controllable way. [Extracted from the article]

Comprehensive Summary: This review presents a comprehensive examination of fully conjugated covalent organic frameworks (COFs), which constitute an emerging class of porous materials with immense potential for diverse applications. This article focuses on diversified fully conjugated COFs, including sp2 carbon‐carbon linkages, pyrazine linkages, benzobisoxazole linkages, dioxin linkages, β‐aminoalkenone linkages, etc. The synthesis techniques and structural attributes of these COFs are expounded upon in great detail, along with their potential applications in various fields. The review thus provides a valuable resource for researchers keen on delving into the synthesis and applications of fully conjugated COFs, thereby highlighting their potential for developing novel functional materials with distinctive properties. [ABSTRACT FROM AUTHOR]