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Electrocatalytic nitrate reduction reaction (NO3−RR) is an important route for sustainable NH3 synthesis and environmental remediation. Metal–organic frameworks (MOFs) are one family of promising NO3−RR electrocatalysts, however, there is plenty of room to improve in their performance, calling for new design principles. Herein, a MOF‐on‐MOF heterostructured electrocatalyst with interfacial dual active sites and build‐in electric field is fabricated for efficient NO3−RR to NH3 production. By growing Co‐HHTP (HHTP=2,3,6,7,10,11‐hexahydroxytriphenylene) nanorods on Ni‐BDC (BDC=1,4‐benzenedicarboxylate) nanosheets, experimental and theoretical investigations demonstrate the formation of Ni−O−Co bonds at the interface of MOF‐on‐MOF heterostructure, leading to dual active sites tailed for NO3−RR. The Ni sites facilitate the adsorption and activation of NO3−, while the Co sites boost the H2O decomposition to supply active hydrogen (Hads) for N‐containing intermediates hydrogenation on adjacent Ni sites, cooperatively reducing the energy barriers of NO3−RR process. Together with the accelerated electron transfer enabled by built‐in electric field, remarkable NO3−RR performance is achieved with an NH3 yield rate of 11.46 mg h−1 cm−2 and a Faradaic efficiency of 98.4 %, outperforming most reported MOF‐based electrocatalysts. This work provides new insights into the design of high‐performance NO3−RR electrocatalysts. [ABSTRACT FROM AUTHOR]

Photocatalytic nitrate reduction reaction (NitRR) is a promising route for environment remediation and sustainable ammonia synthesis. To design efficient photocatalysts, the recently emerged nanoarchitectonics approach holds great promise. Here, we report a nanohouse‐like S‐scheme heterjunction photocatalyst with high photocatalytic NitRR performance. The nano‐house has a floor of plate‐like metal organic framework‐based photocatalyst (NH2‐MIL‐125), on which another photocatalyst Co(OH)2 nanosheet is grown while ZIF‐8 hollow cages are also constructed as the surrounding wall/roof. Experimental and simulation results indicate that the positively charged, highly porous and hydrophobic ZIF‐8 wall can modulate the environment in the nanohouse by (i) NO3− enrichment/NH4+ discharge and (ii) suppression of the competitive hydrogen evolution reaction. In combination with the enhanced electron‐hole separation and strong redox capability in the NH2‐MIL‐125@Co(OH)2 S‐scheme heterjunction confined in the nano‐house, the designed photocatalyst delivers an ammonia yield of 2454.9 μmol g−1 h−1 and an apparent quantum yield of 8.02 % at 400 nm in pure water. Our work provides new insights into the design principles of advanced photocatalytic NitRR photocatalyst. [ABSTRACT FROM AUTHOR]

The rational design of high-performance two-electron oxygen reduction reaction (2e-ORR) electrocatalysts is of great significance for sustainable H2O2 production. Herein, we report the synthesis of a transition-metal chalcogenide@metal–organic framework (TMC@MOF) composite material as an efficient 2e-ORR electrocatalyst. Through a partial conversion route using NiFe-MOF nanosheets as precursors, the Ni ions are partially converted into NiS2 nanoparticles, which are embedded in the MOF skeleton with partially preserved crystalline structure and in situ generated mesopores. Experimental and theoretical results demonstrate that the interaction between NiS2 and retained MOFs regulates the electronic structure of Ni sites in NiS2 toward optimized adsorption of oxygen intermediates, enhancing the 2e-ORR selectivity. Additionally, the ultrasmall NiS2 nanoparticles (grain size < 10 nm) expose abundant active sites, and the created mesopores facilitate the mass transfer. Collectively, excellent 2e-ORR performances are achieved with a high selectivity of 96% and a high H2O2 production rate of 4.2 mol gcat−1 h−1. The proposed partial sulfidation strategy paves the way for the design of advanced MOF-based composite materials for various applications. [ABSTRACT FROM AUTHOR]

Quaternary ammonium compounds (QACs) are well‐known for their antimicrobial properties, but their widespread use is limited due to suboptimal antimicrobial efficiency and safety concerns. Recent progress in materials science has paved the way for the development of QAC‐based composites (QACCs). QACCs with diverse compositions have shown enhanced antimicrobial effectiveness and biosafety for various applications, such as food packaging, capacitive deionization, and household antimicrobials. This review provides a comprehensive summary of the synthesis approaches and different types of QACCs. Moreover, this review examines their antimicrobial applications, taking the underlying structure‐activity relationship into consideration. In addition, this perspectives are presented on the remaining challenges and future research directions for the further development of QACCs. It is expected that this review will provide a valuable reference for the design of next generation QACC‐based antimicrobial agents. [ABSTRACT FROM AUTHOR]

In this paper, the mechanism of Dark‐Spot defect in thin film transistor liquid crystal display (TFT‐LCD) and its improvement measures are studied. The Dark‐Spot defect has a strong correlation with Polymer Film on Array (PFA) materials through stress analysis, and the defect can be reduced by a series of improvement we provided from PFA process adjusting and material formula optimizing. [ABSTRACT FROM AUTHOR]

Bacterial infection is a major threat to public health. Nanotechnology offers a solution by combining nanomaterials with antibacterial agents. The development of an effective nanocomposite against drug‐resistant bacteria such as methicillin‐resistant Staphylococcus aureus (MRSA) is highly important yet challenging. Here, an anti‐MRSA core–shell structure is designed, containing antibacterial zeolitic imidazolate framework‐8 (ZIF‐8) as the core and bactericidal benzalkonium chloride (BAC) templated rough‐surface mesostructured silica nanocomposite (RMSN) as the shell. The resultant ZIF‐8@RMSN nanocomposite exhibits sustained release of BAC and zinc ions, effective disruption of the bacterial membrane, generation of oxidative damage of bacterial DNA, leakage of intracellular components, and finally bacterial death. Furthermore, the synergistic antibacterial mechanisms lead to enhanced biofilm elimination performance. In addition, the ZIF‐8@RMSN‐modified band‐aid effectively combats MRSA infection in vivo. This work has provided a promising nanocomposite against MRSA‐related infections. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are promising photocatalysts for hydrogen peroxide (H2O2) synthesis. However, the nature of organic polymers makes the balance between high activity and stability challenging. We demonstrate that the linkage position matters in the design of robust COF photocatalysts with durable high activity without sacrificial reagents. COFs with ortho‐ and para‐linkages (o‐COFs and p‐COFs) were constructed by 1,3,5‐triformylphloroglucinol with benzene‐, pyridine‐, pyrazine‐orthodiamines and paradiamines. The pyrzaine‐containing o‐COFs with two pyridinic nitrogen atoms exhibited a H2O2 production rate of 4396 μmol g−1 h−1 together with long‐time continuous H2O2 photosynthesis performance in pure water (48 h), superior to the corresponding p‐COFs. A four‐step reaction mechanism is proposed by density function calculations. Moreover, the active sites and origin of stability enhancement for o‐COFs are clarified. This work provides a simple and effective molecular design strategy in the design of robust COF photocatalysts for artificial H2O2 photosynthesis. [ABSTRACT FROM AUTHOR]

Photocatalytic N2 fixation is a promising strategy for ammonia (NH3) synthesis; however, it suffers from relatively low ammonia yield due to the difficulty in the design of photocatalysts with both high charge transfer efficiency and desirable N2 adsorption/activation capability. Herein, an S-scheme CoSx/ZnS heterojunction with dual active sites is designed as an efficient N2 fixation photocatalyst. The CoSx/ZnS heterojunction exhibits a unique pocket-like nanostructure with small ZnS nanocrystals adhered on a single-hole CoSx hollow dodecahedron. Within the heterojunction, the electronic interaction between ZnS and CoSx creates electron-deficient Zn sites with enhanced N2 chemisorption and electron-sufficient Co sites with active hydrogen supply for N2 hydrogenation, cooperatively reducing the energy barrier for N2 activation. In combination with the promoted photogenerated electron-hole separation of the S-scheme heterojunction and facilitated mass transfer by the pocket-like nanostructure, an excellent N2 fixation performance with a high NH3 yield of 1175.37 μmol g−1 h−1 is achieved. This study provides new insights into the design of heterojunction photocatalysts for N2 fixation. [ABSTRACT FROM AUTHOR]