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Bacterial quorum sensing systems regulate the production of an ample variety of bioactive extracellular compounds that are involved in interspecies microbial interactions and in the interplay between the microbes and their hosts. The development of new approaches for enabling chemical detection of such cellular activities is important in order to gain new insight into their function and biological significance. In recent years, surface-enhanced Raman scattering (SERS) spectroscopy has emerged as an ultrasensitive analytical tool employing rationally designed plasmonic nanostructured substrates. This review highlights recent advances of SERS spectroscopy for label-free detection and imaging of quorum sensing-regulated processes in the human opportunistic pathogen Pseudomonas aeruginosa. We also briefly describe the challenges and limitations of the technique and conclude with a summary of future prospects for the field. [ABSTRACT FROM AUTHOR]

The article discusses a study which developed a highly effective electric spiked long afterglow organic light-emitting transistor (LAOLET), whose operation relies on a nanofloating gate (NFG) architecture. Topics covered include the fabrication and characteristics of NFG, the fabrication and work mechanism of LAOLETs and characteristics of LAOLETs. Procedures on preparation of solutions and device and pressure sensor fabrication are also cited.

Four distinct zeolitic imidazolate frameworks (ZIFs) are prepared using zinc and cobalt ions with 2-aminobenzimidazole and 2-methylimidazole as linkers to explore their electrochemical properties as platforms for aldehyde detection. The resulting ZIF-based sensors exhibit high sensitivity, low detection limits, and robust performance when applied to real-world samples.

Zinc-ion batteries (ZIBs) are promising energy storage systems due to high energy density, low-cost, and abundant availability of zinc as a raw material. However, the greatest challenge in ZIBs research is lack of suitable cathode materials that can reversibly intercalate Zn 2+ ions. 2D layered materials, especially MoS 2 -based, attract tremendous interest due to large surface area and ability to intercalate/deintercalate ions. Unfortunately, pristine MoS 2 obtained by traditional protocols such as chemical exfoliation or hydrothermal/solvothermal methods exhibits limited electronic conductivity and poor chemical stability upon charge/discharge cycling. Here, a novel molecular strategy to boost the electrochemical performance of MoS 2 cathode materials for aqueous ZIBs is reported. The use of dithiolated conjugated molecular pillars, that is, 4,4'-biphenyldithiols, enables to heal defects and crosslink the MoS 2 nanosheets, yielding covalently bridged networks (MoS 2 -SH2) with improved ionic and electronic conductivity and electrochemical performance. In particular, MoS 2 -SH2 electrodes display high specific capacity of 271.3 mAh g -1 at 0.1 A g -1 , high energy density of 279 Wh kg -1 , and high power density of 12.3 kW kg -1 . With its outstanding rate capability (capacity of 148.1 mAh g -1 at 10 A g -1 ) and stability (capacity of 179 mAh g -1 after 1000 cycles), MoS 2 -SH2 electrodes outperform other MoS 2 -based electrodes in ZIBs., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

Core-shell MOF@COF hybrids were synthesized via subsequent modification of MOF UiO-66-NH 2 with 1,3,5-triformylphloroglucinol (TFP) and 2,3,5,6-tetraaminobenzoquinone (TABQ). The hybrids exhibited significant surface area (236 m 2 g -1 ) and outstanding electrochemical performance (103 F g -1 at 0.5 A g -1 ), surpassing both COFs and MOFs, thereby showcasing the potential of on-surface condensation reactions for developing high-performance energy storage devices.

The coupling of different 2D materials (2DMs) to form van der Waals heterostructures (vdWHs) is a powerful strategy for adjusting the electronic properties of 2D semiconductors, for applications in opto-electronics and quantum computing. 2D molybdenum disulfide (MoS 2 ) represents an archetypical semiconducting, monolayer thick versatile platform for the generation of hybrid vdWH with tunable charge transport characteristics through its interfacing with molecules and assemblies thereof. However, the physisorption of (macro)molecules on 2D MoS 2 yields hybrids possessing a limited thermal stability, thereby jeopardizing their technological applications. Herein, the rational design and optimized synthesis of 2D covalent organic frameworks (2D-COFs) for the generation of MoS 2 /2D-COF vdWHs exhibiting strong interlayer coupling effects are reported. The high crystallinity of the 2D-COF films makes it possible to engineer an ultrastable periodic doping effect on MoS 2 , boosting devices' field-effect mobility at room temperature. Such a performance increase can be attributed to the synergistic effect of the efficient interfacial electron transfer process and the pronounced suppression of MoS 2 's lattice vibration. This proof-of-concept work validates an unprecedented approach for the efficient modulation of the electronic properties of 2D transition metal dichalcogenides toward high-performance (opto)electronics for CMOS digital circuits., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

The unique electrochemical properties of polyoxometalates (POMs) render them ideal components for the fabrication of next-generation high-performance energy storage systems. However, their practical applications have been hindered by their high solubility in common electrolytes. This problem can be overcome by the effective hybridization of POMs with other materials. Here we present the design and synthesis of two novel polyoxometalate-covalent organic frameworks (POCOF) via one-pot solvothermal strategy between an amino-functionalized Anderson-type POM and a trialdehyde-based building unit. We show that structural and functional complexity can be enriched by adding hydroxyl groups in the 2,4,6 position to the benzene-1,3,5-tricarbaldehyde allowing to exploit for the first time in POCOFs the keto-enol tautomerization as additional feature to impart greater chemical stability to the COFs and enhanced properties leading to large specific surface area (347 m 2 /g) and superior electrochemical performance of the POCOF-1 electrodes, when compared with POCOF-2 electrodes that possess only imine-type linkage and with pristine POM electrodes. Specifically, POCOF-1 electrodes display remarkable specific, areal, and volumetric capacitance (125 F/g, 248 mF/cm 2 and 41.9 mF/cm 3 , respectively) at a current density of 0.5 A/g, a maximum energy density (56.2 Wh/kg), a maximum power density (3.7 kW/kg) and an outstanding cyclability (90 % capacitance retention after 5000 cycles)., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Two-dimensional covalent organic frameworks (COFs) have emerged as promising materials for energy storage applications exhibiting enhanced electrochemical performance. While most of the reported organic cathode materials for zinc-ion batteries use carbonyl groups as electrochemically-active sites, their high hydrophilicity in aqueous electrolytes represents a critical drawback. Herein, we report a novel and structurally robust olefin-linked COF-TMT-BT synthesized via the aldol condensation between 2,4,6-trimethyl-1,3,5-triazine (TMT) and 4,4'-(benzothiadiazole-4,7-diyl)dibenzaldehyde (BT), where benzothiadiazole units are explored as novel electrochemically-active groups. Our COF-TMT-BT exhibits an outstanding Zn 2+ storage capability, delivering a state-of-the-art capacity of 283.5 mAh g -1 at 0.1 A g -1 . Computational and experimental analyses reveal that the charge-storage mechanism in COF-TMT-BT electrodes is based on the supramolecularly engineered and reversible Zn 2+ coordination by the benzothiadiazole units., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Janus two-dimensional materials (2DMs) are a novel class of 2DMs in which the two faces of the material are either asymmetrically functionalized or are exposed to a different local environment. The diversity of the properties imparted to the two opposing sides enables the design of new multifunctional materials for applications in a broad variety of fields including opto-electronics, energy storage, and catalysis. In this perspective, we summarize the most enlightening experimental methods for the asymmetric chemical functionalization of 2DMs with tailored made (macro)molecules by means of a supratopic binding (one side) or antaratopic binding (two sides) process. We describe the emergence of unique electrical and optical characteristics resulting from the asymmetric dressing of the two surfaces. Representative examples of Janus 2DMs towards bandgap engineering, enhanced photoresponse and photoluminescence are provided. In addition, examples of Janus 2DMs for real applications such as energy storage (batteries and supercapacitors) and generation (photovoltaics), opto-electronics (field-effect transistors and photodetectors), catalysis, drug delivery, self-healing materials, chemical sensors and selective capture and separation of small molecules are also described. Finally, we discuss the future directions, challenges, and opportunities to expand the frontiers of Janus 2DMs towards technologies with potential impact in environmental science and biomedical applications., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

In this minireview, we summarize current research dealing with the combination of noble-metal nanoparticles and different families of supramolecular macrocycles (cyclodextrins, cucurbit[n]urils, calixarenes, and pillar[n]arenes). We intended to select relevant publications on the synthesis of noble-metal nanoparticles with macrocycles acting as capping agents or/and reducing agents, as well as on the post-synthetic metal-nanoparticle modification with macrocycles. We also discuss strategies in which supramolecular chemistry is applied to direct the self-assembly of nanoparticles and formation of polymer composites. We finally describe the main applications of these materials in various fields., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We present a simple procedure for the synthesis of quasi-spherical Au nanoparticles in a wide size range mediated by macrocyclic host molecules, ammonium pillar[5]arene (AP[5]A). The strategy is based on a seeded growth process in which the water-soluble pillar[5]arene undergoes complexation of the Au salt through the ammonium groups, thereby avoiding Au nucleation, while acting as a stabilizer. The presence of the pillar[5]arene onto the Au nanoparticle particle surface is demonstrated by surface-enhanced Raman scattering (SERS) spectroscopy, and the most probable conformation of the molecule when adsorbed on the Au nanoparticles surface is suggested on the basis of theoretical calculations. In addition, we analyze the host-guest interactions of the AP[5]A with 2-naphthoic acid (2NA) by using (1)H NMR spectroscopy and the results are compared with theoretical calculations. Finally, the promising synergetic effects of combining supramolecular chemistry and metal nanoparticles are demonstrated through SERS detection in water of 2NA and a polycyclic aromatic hydrocarbon, pyrene (PYR)., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)