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Research is presented describing the molecular electronic study of thiolate monolayers.

A fluidic glycan microarray, with glycan density varying for orders of magnitude, is applied to profile cell surface interaction by using a model system, the adhesion of Escherichia coli to mannose. The studies have shown that the new mechanism disclosed by the fluidic microarray is of general significance to cell surface interactions, where the dynamic clustering of simple sugar groups on the fluidic membrane surface may simulate the functions of complex glycan molecules.

A method is described for forming fluidic and air-stable supported lipid bilayers (SLBs) through tethered and dispersed cholesterol groups incorporated into the bottom leaflet. The studies have shown their application as cell membrane--mimicking microarrays by reconstituting peripheral as well as integral membrane components that can be recognized by their respective targets.

A novel chemical approach for the efficient assembly of organic molecules on silicon surfaces using the Si-N linkage was described. The approach was achieved by the efficient reaction between an amine functional group and a chlorinated silicon surface. The N anchor was believed to be a bridge between two surface silicon atoms. The method was found to be generally applicable for the assembly of a variety of functional organic molecules under vacuum environment or in solution.

The article discusses the quantitative application of DNA microarrays in proteomics in the U.S. The difficulty in the application results in a large part from the lack of understanding and control of the chemical and physical processes involved in probe immobilization. A survey of protein microarray literature suggests that one of the major reasons for poor reproducibility is nonuniform spot profile.

The article discusses the correlation between highest-occupied molecular orbital (HOMO) alignment and contact resistance in molecular junctions. It used conducting probe atomic force microscopy to measure transport and ultraviolet photoemission spectroscopy to establish the valence electronic structure. The difference in the HOMO positions for the two series of molecules does not appear to affect the length dependence of the junction resistance.

Adsorptive separation of Xe and Kr is an industrially promising but challenging process because of their identical shape and similar physicochemical properties. Herein, we demonstrate a strategy through rationally designing the linkers of anionic functional ultramicroporous materials (FUMs) to finely regulate the pore chemistry and architecture, which creates unique stepped channels incorporating dense polar nanotraps to generate a larger effective pore space and enables dense packing of Xe. A new hydrolytically stable FUM (ZUL-530) was prepared, which for the first time achieves a Xe packing density exceeding the liquid Xe density at atmospheric conditions in metal-organic frameworks (MOFs) (based on experimental data), resulting in both excellent Xe uptake (2.55 mmol g -1 at 0.2 bar) and high IAST selectivity (20.5). GCMC and DFT-D calculations reveal the essential role of the stepped traps in the dense packing of Xe. Breakthrough experiments demonstrate remarkable productivities of both high-purity Kr (6.70 mmol g -1 ) and Xe (1.78 mmol g -1 ) for the Xe/Kr (20:80) mixture. In a model nuclear industry exhaust gas, ZUL-530 exhibits a top-class Xe dynamic capacity (28.8 mmol kg -1 ) for trace Xe, which proves it is one of the best candidates for Xe/Kr separation.

Searching for high energy-density electrode materials for sodium ion batteries has revealed Na-deficient intercalation compounds with lattice oxygen redox as promising high-capacity cathodes. However, anionic redox reactions commonly encountered poor electrochemical reversibility and unfavorable structural transformations during dynamic (de)sodiation processes. To address this issue, we employed lithium orbital hybridization chemistry to create Na-O-Li configuration in a prototype P2-layered Na 43/60 Li 1/20 Mg 7/60 Cu 1/6 Mn 2/3 O 2 (P2-NaLMCM') cathode material. That Li + ions, having low electronegativity, reside in the transition metal slabs serves to stimulate unhybridized O 2p orbitals to facilitate the stable capacity contribution of oxygen redox at high state of charge. The prismatic-type structure evolving to an intergrowth structure of the Z phase at high charging state could be simultaneously alleviated by reducing the electrostatic repulsion of O-O layers. As a consequence, P2-NaLMCM' delivers a high specific capacity of 183.8 mAh g -1 at 0.05 C and good cycling stability with a capacity retention of 80.2% over 200 cycles within the voltage range of 2.0-4.5 V. Our findings provide new insights into both tailoring oxygen redox chemistry and stabilizing dynamic structural evolution for high-energy battery cathode materials.

Quantum dots (QDs) exhibit superior brightness and photochemical stability, making them the preferred option for highly sensitive single-molecule detection compared with fluorescent dyes or proteins. Nevertheless, their high surface energy leads to nonspecific adsorption and poor colloidal stability. In the past decades, we have found that QD-based fluorescent nanoparticles (FNs) can not only address these limitations but also enhance detection sensitivity. However, the photoluminescence quantum yield (PLQY) of FNs is significantly lower compared with that of original QDs. It is urgent to develop a strategy to solve the issue, aiming to further enhance detection sensitivity. In this study, we found that the decrease of PLQY of FNs prepared by free radical polymerization was attributed to two factors: (1) generation of defects that can cause nonradiative transitions resulting from QD-ligands desorption and QD-shell oxidation induced by free radicals; (2) self-absorption resulting from aggregation caused by incompatibility of QDs with polymers. Based on these, we proposed a multihierarchical regulation strategy that includes: (1) regulating QD-ligands; (2) precisely controlling free radical concentration; and (3) constructing cross-linked structures of polymer to improve compatibility and to reduce the formation of surface defects. It is crucial to emphasize that the simultaneous coordination of multiple factors is essential. Consequently, a world-record PLQY of 97.6% for FNs was achieved, breaking through the current bottleneck at 65%. The flexible application of this regulatory concept paves the way for the large-scale production of high-brightness QD-polymer complexes, enhancing their potential applications in sensitive biomedical detection.

We recently reported on small-molecule inhibitors of the GroES/GroEL chaperone system as potential antibiotics against Escherichia coli and the ESKAPE pathogens but were unable to establish GroES/GroEL as the cellular target, leading to cell death. In this study, using two of our most potent bis -sulfonamido-2-phenylbenzoxazoles (PBZs), we established the binding site of the PBZ molecules using cryo-EM and found that GroEL was the cellular target responsible for the mode of action. Cryo-EM revealed that PBZ1587 binds at the GroEL ring-ring interface (RRI). A cellular reporter assay confirmed that PBZ1587 engaged GroEL in cells, but cellular rescue experiments showed potential off-target effects. This prompted us to explore a closely related analogue, PBZ1038, which is also bound to the RRI. Biochemical characterization showed potent inhibition of Gram-negative chaperonins but much lower potency of chaperonin from a Gram-positive organism, Enterococcus faecium . A cellular reporter assay showed that PBZ1038 also engaged GroEL in cells and that the cytotoxic phenotype could be rescued by a chromosomal copy of E. faecium GroEL/GroES or by expressing a recalcitrant RRI mutant. These data argue that PBZ1038's antimicrobial action is exerted through inhibition of GroES/GroEL, validating this chaperone system as an antibiotic target.

Heterophase nanomaterials have sparked significant research interest in catalysis due to their distinctive properties arising from synergistic effects of different components and the formed phase boundary. However, challenges persist in the controlled synthesis of heterophase intermetallic compounds (IMCs), primarily due to the lattice mismatch of distinct crystal phases and the difficulty in achieving precise control of the phase transitions. Herein, orthorhombic/cubic Ru 2 Ge 3 /RuGe IMCs with engineered boundary architecture are synthesized and anchored on the reduced graphene oxide. The Ru 2 Ge 3 /RuGe IMCs exhibit excellent hydrogen evolution reaction (HER) performance with a high current density of 1000 mA cm -2 at a low overpotential of 135 mV. The presence of phase boundaries enhances charge transfer and improves the kinetics of water dissociation while optimizing the processes of hydrogen adsorption/desorption, thus boosting the HER performance. Moreover, an anion exchange membrane electrolyzer is constructed using Ru 2 Ge 3 /RuGe as the cathode electrocatalyst, which achieves a current density of 1000 mA cm -2 at a low voltage of 1.73 V, and the activity remains virtually undiminished over 500 h.

Carbon is commonly used as an electrode material for supercapacitors operating on an electrical double-layer energy storage mechanism. However, the low specific capacitance limits its application. Increasing the specific surface area is by far the most common expansion method, and surprisingly, they are not always positively correlated. The overmuch specific surface will show the characteristics of nanoconfinement, and the potential synergistic enhancement mechanism of various key parameters is still controversial. In this work, carbon fiber electrodes with different ultramicropore structures were designed in order to improve the utilization rate and the discharge capacitance. It has been found that when the ultramicropore entrance's surface is too small, it will lead to the decrease of the external charge of the pore transport channel, and then, the selectivity of the opposite ions will decrease. The numerical simulation based on Poisson and Nernst-Planck equations also indicates that ions have difficulty diffusing into the micropores when their entrance surface decreases. Surface properties within the nanocontainment space become critical factors influencing ion transport and adsorption. The specific discharge capacitance of carbon fiber is increased from 3 to 1430 mF cm -2 .

Electrocatalytic nitrate (NO 3 - ) reduction reaction (NO 3 RR) holds great potential for the conversion of NO 3 - contaminants into valuable NH 3 in a sustainable method. Unfortunately, the nonequilibrium adsorption of intermediates and sluggish multielectron transfer have detrimental impacts on the electrocatalytic performance of the NO 3 RR, posing obstacles to its practical application. Herein, we initially screen the adsorption energies of three key intermediates, i.e., *NO 3 , *NO, and *H 2 O, along with the d-band centers on 21 types of transition metal (IIIV and IB)-Sb/Bi-based intermetallic compounds (IMCs) as electrocatalysts. The results reveal that hexagonal CoSb IMCs possess the optimal adsorption equilibrium for key intermediates and exhibit outstanding electrocatalytic NO 3 RR performance with a Faradaic efficiency of 96.3%, a NH 3 selectivity of 89.1%, and excellent stability, surpassing the majority of recently reported NO 3 RR electrocatalysts. Moreover, the integration of CoSb IMCs/C into a novel Zn-NO 3 - battery results in a high power density of 11.88 mW cm -2 .