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The misuse of antibiotics leads to emergence of drug‐resistant bacteria. Developing artificial nanozymes with high stability and excellent catalytic performance is desirable to substitute for antibiotics, but still remains huge challenge. Herein, the study reports a new strategy for cascaded enhanced peroxidase (POD) reaction driving antibacterial therapy via constructing 2D conjugated metal‐organic frameworks (MOFs) with non coordination saturation as nanozyme. It is demonstrated that the non coordination saturation Cu atom promotes the adsorption of H2O2, followed by the Cu‐HHTP MOFs with high conjugated structure can enhance the photogenerated electron transfer for ·OH generation in POD reaction. The sequential enhancement of substrate adsorption and decomposition endows the as‐made Cu‐HHTP MOFs with outstanding antibacterial property of >99.9999% elimination with a concentration only 1/133 that of traditional nanozyme. In addition, the study also certifies its excellent in vivo antimicrobial activity and biocompatibility, indicating the therapeutic potential for infections by drug‐resistant bacteria. [ABSTRACT FROM AUTHOR]

Facile synthesis and post‐processing of covalent organic frameworks (COFs) under mild synthetic conditions are highly sought after and important for widespread utilizations in catalysis and energy storage. Here we report the synthesis of the chemically stable aza‐fused COFs BPT‐COF and PT‐COF by a liquid‐phase method. The process involves the spontaneous polycondensation of vicinal diamines and vicinal diketones, and is driven by the near‐equilibrium growth of COF domains at a very low monomer concentration. The method permits in situ assembly of COFs and COF‐GO hybrid materials and leads to the formation of a uniform conducting film on arbitrary substrates on vacuum filtration. When used as electrocatalysts, the as‐prepared membranes show a fast hydrogen evolution reaction (HER) with a low overpotential (45 mV at 10 mA cm−2) and a small Tafel slope (53 mV dec−1), which are the best among metal‐free catalysts. Our results may open a new route towards the preparation of highly π‐conjugated COFs for multifunctional applications. [ABSTRACT FROM AUTHOR]

Owing to their excellent physical and electrical properties, metal–organic framework (MOF) materials with well‐defined supramolecular structures have received extensive research attention. However, the fabrication of large‐area two‐dimensional (2D) MOF films is still a significant challenge. Herein, we propose a novel electrochemical (EC) synthesis method for the preparation of large‐area Cu3(HHTP)2 MOF film on single‐crystal Cu (100) anode. The surface reaction was achieved via charge‐induced molecular assembly. The synthesized MOF film exhibited a high crystalline quality with an electrical conductivity of approximately 0.087 S cm−1, which was around 1000 times larger than the previously reported values for the same material prepared by the interface method. In addition, Cu2(MTCP), Cu3(BTPA)2, and Cu3(TPTC)2 MOF films were synthesized on Cu foil with the same strategy, which confirmed the universality of the proposed method. This controllable EC method can be effectively applied to the industrial‐scale production of 2D MOF films on Cu foil. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) powder was modified with γ-mercaptopropyl trimethoxysilane (KH590) and tetramethylammonium hydroxide (TMAH). The effects of modification were investigated following viscosity measurements, which confirmed the high dispersibility in water of the modified SiC powder. The maximum solids content of the slurry prepared using the modified SiC powder (ca. 76% vol.) was determined after optimization of the modification conditions. Overall, the results of viscosity and solid content indicate that the proposed modifications result in a SiC powder that is superior compared to that prepared by the Saint-Gobain's method. [ABSTRACT FROM AUTHOR]

Constructing uniform covalent organic framework (COF) film on substrates for electronic devices is highly desirable. Here, a simple and mild strategy is developed to prepare them by polymerization on a solid-liquid interface. The universality of the method is confirmed by the successful preparation of five COF films with different microstructures. These films have large lateral size, controllable thickness, and high crystalline quality. And COF patterns can also be directly achieved on substrates via hydrophilic and hydrophobic interface engineering, which is in favor of preparing device array. For application studies, the PyTTA-TPA (PyTTA: 4,4',4'',4'''-(1,3,6,8-Tetrakis(4-aminophenyl)pyrene and TPA: terephthalaldehyde) COF film has a high photoresponsivity of 59.79 μA W -1 at 420 nm for photoelectrochemical (PEC) detection. When employed as an active material for optoelectronic synaptic devices for the first attempt, it shows excellent light-stimulated synaptic plasticity properties such as short-term plasticity (STP), long-term plasticity (LTP), and the conversion of STP to LTP, which can be used to simulate biological synaptic functions., (© 2024 Wiley-VCH GmbH.)

Photocorrosion of highly active photocatalysts is an urgent problem to be solved in the field of photocatalysis; however, searching for effective strategies for inhibiting photocorrosion of photocatalysts is still a grand challenge. Herein, we design and construct a class of Cu 2 O/2D PyTTA-TPA COFs (PyTTA: 1,3,6,8-Tetrakis(4-aminophenyl)pyrene, TPA: p-benzaldehyde) core/shell nanocubes to greatly boost the performance of photocatalytic hydrogen evolution and significantly inhibit the photocorrosion. The optimal Cu 2 O/PyTTA-TPA COFs core/shell nanocubes exhibit an excellent photocatalytic H 2 evolution rate of 12.5 mmol h -1 g -1 , which is ∼8.0-fold and ∼20.0-fold higher than those of PyTTA-TPA COFs and Cu 2 O nanocube, respectively, and also is the best in all the reported metal oxides catalytic materials. The mechanism studies demonstrate that the appropriate matching band gaps and tight integration of PyTTA-TPA COFs and Cu 2 O nanocubes can significantly facilitate the separation of photogenerated electron-hole pairs in the Cu 2 O/PyTTA-TPA COFs core/shell nanocube during the photocatalytic process, which ameliorates the photocatalytic H 2 evolution activity. Most importantly, the 2D PyTTA-TPA COFs shell with outstanding intrinsic stability protects Cu 2 O nanocubes core from photocorrosion by showing no morphology and crystal structure change after 1000 times of photoexcitation.