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Oxygen vacancies are one of the prominent types of defects in metal oxides. In addition to their role in modifying the electronic properties in solids, these sites have been shown to activate chemical bonds. As a result, the use of defect‐rich metal oxides in the organic transformations is promising. The article gives an overview of various chemical processes that are in use for the chemical reduction of aromatic nitro compounds to amines. Recently, application of oxygen vacancies in transition metal oxide for the selective reduction of aromatic nitro compounds to the corresponding amines has emerged as a new method of synthesis of amines. Oxygen vacancies in reducible oxide such as CuO have been shown to decompose hydrazine hydrate to H2 and in situ cause the reduction of nitro arenes to corresponding amines. This concept article discusses the literature pertaining to the synthesis of nitro reduction reaction, various strategies employed thus far and the place the defect‐mediated synthesis holds. The article also discusses the perspectives and challenges that remain to be addressed to gain more insights into the mechanistic understanding of the role of oxygen vacancies in nitro reduction and beyond. [ABSTRACT FROM AUTHOR]

Benchtop NMR provides improved accessibility in terms of cost, space, and technical expertise. In turn, this encourages new users into the field of NMR spectroscopy. Unfortunately, many interesting samples in education and research, from beer to whole blood, contain significant amounts of water that require suppression in 1H NMR in order to recover sample information. However, due to the significant reduction in chemical shift dispersion in benchtop NMR systems, the sample signals are much closer to the water resonance compared to those in a corresponding high‐field NMR spectrum. Therefore, simply translating solvent suppression experiments intended for high‐field NMR instruments to benchtop NMR systems without careful consideration can be problematic. In this study, the effectiveness of several popular water suppression schemes was evaluated for benchtop NMR applications. Emphasis is placed on pulse sequences with no, or few, adjustable parameters making them easy to implement. These fall into two main categories: (1) those based on Pre‐SAT including Pre‐SAT, PURGE, NOESY‐PR, and g‐NOESY‐PR and (2) those based on binomial inversion including JRS and W5‐WATERGATE. Among these schemes, solvent suppression sequences based on Pre‐SAT offer a general approach for easy solvent suppression for samples with higher analyte concentrations (sucrose standard and Redbull™). However, for human urine, binomial‐like sequences were required. In summary, it is demonstrated that highly efficient water suppression approaches can be implemented on benchtop NMR systems in a simple manner, despite the limited spectral dispersion, further illustrating the potential for widespread implementation of these approaches in education and research. [ABSTRACT FROM AUTHOR]

Optimally increasing the catalytic activity of Co3O4‐based materials is crucial for promoting their practical applications for acetone detection; however, this still remains challenging. Herein, a strategy is proposed in this work to increase the catalytic activity of Co3O4 toward the oxidation of acetone through the synergistic effect of boron doping and chemical reduction, which can substantially improve the sensing performance for acetone detection. The characterization results confirm that the present strategy facilitates the formation of more oxygen vacancies and increases the content of Co2+ ions serving as active sites. As expected, the optimal sensor yields a higher response. To extend the practical application to the auxiliary diagnosis of diabetes through exhaled breath, the optimal sensors distinguished between acetone concentrations in the breath of healthy individuals and in the simulated breath of patients with diabetes. Detailed gas‐sensing measurements reveal that the enhanced acetone sensing performance is attributed to the increased catalytic activity of materials for oxidation of acetone by the Mars–van Krevelen, Langmuir–Hinshelwood, and Eley–Rideal mechanisms. This study provides new insights into the fabrication of high‐performance metal oxide‐based gas sensors by improving the catalytic activity of sensing materials. [ABSTRACT FROM AUTHOR]

Chemical reduction of a [4]cumulene with cesium metal was explored, and the structural changes stemming from electron acquisition are detailed using X‐ray crystallography. It is found that the [4]cumulene undergoes dramatic geometric changes upon stepwise reduction, including bending of the cumulenic core and twisting of the endgroups from orthogonal to planar. The structural deformation is consistent with early theoretical reports that suggest that the twisting should occur upon reduction of both even and odd [n]cumulenes. The current results, on the other hand, are inconsistent with a previous experimental study of a [3]cumulene in which the predicted twisting is not observed upon reduction. DFT calculations reveal that the barrier to deformation is an order of magnitude lower in a [3]cumulene than a [4]cumulene, allowing the barrier to be overcome in the solid‐state. [ABSTRACT FROM AUTHOR]

Molybdenum‐ or tungsten‐dependent formate dehydrogenases have emerged as significant catalysts for the chemical reduction of CO2 to formate, with biotechnological applications envisaged in climate‐change mitigation. The role of Met405 in the active site of Desulfovibrio vulgaris formate dehydrogenase AB (DvFdhAB) has remained elusive. However, its proximity to the metal site and the conformational change that it undergoes between the resting and active forms suggests a functional role. In this work, the M405S variant was engineered, which allowed the active‐site geometry in the absence of methionine Sδ interactions with the metal site to be revealed and the role of Met405 in catalysis to be probed. This variant displayed reduced activity in both formate oxidation and CO2 reduction, together with an increased sensitivity to oxygen inactivation. [ABSTRACT FROM AUTHOR]

Glycerol (GL) represents a widespread agro‐industrial waste. Its valorization is pivotal for a sustainable society because GL is a renewable compound deriving from biomass, but it has a high oxygen to carbon ratio, compared with feedstock used in the energy and chemistry sectors. Oxygen‐poor derivatives are easily and immediately transferable to the industry, avoiding a deep and pressing modification of the plants. From this perspective, keeping the carbon content but with an oxygen content reduction, we could effectively obtain the enhancement of the recovery and the use of GL converting it into attractive industrial building‐blocks. In this Review, we present and discuss the up‐to‐date results about the chemical reduction of GL into products with 3 carbon and 0, 1, or 2 oxygen atoms. The focus is on the transition metal (TM) catalysts that have made the hydrogenation reactions of GL possible, partitioning the metals into early and late, based on their position in the periodic table. This discussion will contribute to select and develop new catalysts aimed at the improvement of the yield and of the selectivity in the hydrogenation reactions of GL. [ABSTRACT FROM AUTHOR]

Exploration of the reduction chemistry of the 2,2'‐bipyridine (bipy) lanthanide metallocene complexes Cp*2LnCl(bipy) and Cp*2Ln(bipy) (Cp* = C5Me5) resulted in the isolation of a series of complexes with unusual composition and structure including complexes with a single Cp* ligand, multiple azide ligands, and bipy ligands with close parallel orientations. These results not only reveal new structural types, but they also show the diverse chemistry displayed by this redox‐active platform. Treatment of Cp*2NdCl(bipy) with excess KC8 resulted in the formation of the mono‐Cp* Nd(III) complex, [K(crypt)]2[Cp*Nd(bipy)2], 1, as well as [K(crypt)][Cp*2NdCl2], 2, and the previously reported [K(crypt)][Cp*2Nd(bipy)]. A mono‐Cp* Lu(III) complex, Cp*Lu(bipy)2, 3, was also found in an attempt to make Cp*2Lu(bipy) from LuCl3, 2 equiv. of KCp*, bipy, and K/KI. Surprisingly, the (bipy)1− ligands in neighboring molecules in the structure of 3 are oriented in a parallel fashion with intermolecular C⋅⋅⋅C distances of 3.289(4) Å, which are shorter than the sum of van der Waals radii of two carbon atoms, 3.4 Å. Another product with one Cp* ligand per lanthanide was isolated from the reaction of [K(crypt)][Cp*2Eu(bipy)] with azobenzene, which afforded the dimeric Eu(II) complex, [K(crypt)]2[Cp*Eu(THF)(PhNNPh)]2, 4. Attempts to make 4 from the reaction between Cp*2Eu(THF)2 and a reduced azobenzene anion generated instead the mixed‐valent Eu(III)/Eu(II) complex, [K(crypt)][Cp*Eu(THF)(PhNNPh)]2, 5, which allows direct comparison with the bimetallic Eu(II) complex 4. Mono‐Cp* complexes of Yb(III) are obtained from reactions of the Yb(II) complex, [K(crypt)][Cp*2Yb(bipy)], with trimethylsilylazide, which afforded the tetra‐azido [K(crypt)]2[Cp*Yb(N3)4], 6, or the di‐azido complex [K(crypt)]2[Cp*Yb(N3)2(bipy)], 7 a, depending on the reaction stoichiometry. A mono‐Cp* Yb(III) complex is also isolated from reaction of [K(crypt)][Cp*2Yb(bipy)] with elemental sulfur which forms the mixed polysulfido Yb(III) complex [K(crypt)]2[Cp*Yb(S4)(S5)], 8 a. In contrast to these reactions that form mono‐Cp* products, reduction of Cp*2Yb(bipy) with 1 equiv. of KC8 in the presence of 18‐crown‐6 resulted in the complete loss of Cp* ligands and the formation of [K(18‐c‐6)(THF)][Yb(bipy)4], 9. The (bipy)1− ligands of 9 are arranged in a parallel orientation, as observed in the structure of 3, except in this case this interaction is intramolecular and involves pairs of ligands bound to the same Yb atom. Attempts to reduce further the Sm(II) (bipy)1− complex, Cp*2Sm(bipy) with 2 equiv. of KC8 in the presence of excess 18‐crown‐6 led to the isolation of a Sm(III) salt of (bipy)2− with an inverse sandwich Cp* counter‐cation and a co‐crystallized K(18‐c‐6)Cp* unit, [K2(18‐c‐6)2Cp*]2[Cp*2Sm(bipy)]2 ⋅ [K(18‐c‐6)Cp*], 10. [ABSTRACT FROM AUTHOR]

BACKGROUND: Improvements in farmland soil organic carbon (SOC) stock enhance crop yield and soil fertility while mitigating climate change. Rational fertilization in agricultural production is crucial for safeguarding SOC stock. In this study, field experiments were conducted with different ratios of chemical fertilizer reduction and organic fertilizer substitution for three consecutive years (2018--2020) to explore their effects and interlinkages on SOC fractions, soil properties and SOC stock. RESULTS: The results showed that organic fertilizer substitution increased SOC and its fractions content, SOC stock (by 3.98-- 12.98% and 7.15--18.13%) and soil fertility index (by 11.76--49.26% and 33.33--91.47%) compared to conventional fertilization in 2019 and 2020, while chemical fertilizer reduction had the opposite effect. Moreover, soil properties (except total nitrogen to total phosphorus ratio, N/P) and SOC fractions significantly affected SOC stock, with SOC fractions contributing more than soil properties. The high sensitivity of microbial biomass carbon (MBC) and dissolved organic carbon (DOC) can indicate changes in soil carbon pool. Structural equation modeling (SEM) revealed that organic fertilizer substitution increased SOC content and stock by increasing SOC fractions [recalcitrant organic carbon (ROC) and labile organic carbon (LOC) fractions] content and soil fertility. CONCLUSIONS: Our study revealed the corresponding mechanisms of the two fertilization modes affecting SOC stock changes. The use of organic fertilizer substitution is recommended to increase SOC stocks and soil fertility in wheat fields. [ABSTRACT FROM AUTHOR]

Silver nanoparticles have shown inhibitory capabilities and its use in battling viral infections are strengthened by its potent antibacterial activity. Notably, since it directly affects antiviral efficacy, the proper choice of synthesis process for making silver nanoparticles is a vital element to be taken into consideration. The synthesis of silver nanoparticles for the treatment of viral and bacterial infections involves creating silver particles at the nanoscale with unique antimicrobial properties. Various methods exist for synthesizing silver nanoparticles, including chemical reduction, green synthesis, and physical methods. Chemical reduction involves using reducing agents to convert silver ions into silver nanoparticles. Green synthesis employs reducing agents in an environmentally friendly manner. Physical methods rely on techniques such as laser ablation or thermal evaporation to produce silver nanoparticles. In order to provide technological guidance for choosing antiviral silver nanoparticle manufacturing methods, this paper introduces and explores alternative synthesis methods for creating silver nanoparticles. [ABSTRACT FROM AUTHOR]

Solid electrolyte interphase (SEI) makes the electrochemical window of aqueous electrolytes beyond the thermodynamics limitation of water. However, achieving the energetic and robust SEI is more challenging in aqueous electrolytes because the low SEI formation efficiency (SFE) only contributed from anion‐reduced products, and the low SEI formation quality (SFQ) negatively impacted by the hydrogen evolution, resulting in a high Li loss to compensate for SEI formation. Herein, we propose a highly efficient strategy to construct Spatially‐Temporally Synchronized (STS) robust SEI by the involvement of synergistic chemical precipitation‐electrochemical reduction. In this case, a robust Li3PO4‐rich SEI enables intelligent inherent growth at the active site of the hydrogen by the chemical capture of the OH− stemmed from the HER to trigger the ionization balance of dihydrogen phosphate (H2PO4−) shift to insoluble solid Li3PO4. It is worth highlighting that the Li3PO4 formation does not extra‐consume lithium derived from the cathode but makes good use of the product of HER (OH−), prompting the SEI to achieve 100 % SFE and pushing the HER potential into −1.8 V vs. Ag/AgCl. This energetic and robust SEI offers a new way to achieve anion/concentration‐independent interfacial chemistry for the aqueous batteries. [ABSTRACT FROM AUTHOR]

Solid electrolyte interphase (SEI) makes the electrochemical window of aqueous electrolytes beyond the thermodynamics limitation of water. However, achieving the energetic and robust SEI is more challenging in aqueous electrolytes because the low SEI formation efficiency (SFE) only contributed from anion‐reduced products, and the low SEI formation quality (SFQ) negatively impacted by the hydrogen evolution, resulting in a high Li loss to compensate for SEI formation. Herein, we propose a highly efficient strategy to construct Spatially‐Temporally Synchronized (STS) robust SEI by the involvement of synergistic chemical precipitation‐electrochemical reduction. In this case, a robust Li3PO4‐rich SEI enables intelligent inherent growth at the active site of the hydrogen by the chemical capture of the OH− stemmed from the HER to trigger the ionization balance of dihydrogen phosphate (H2PO4−) shift to insoluble solid Li3PO4. It is worth highlighting that the Li3PO4 formation does not extra‐consume lithium derived from the cathode but makes good use of the product of HER (OH−), prompting the SEI to achieve 100 % SFE and pushing the HER potential into −1.8 V vs. Ag/AgCl. This energetic and robust SEI offers a new way to achieve anion/concentration‐independent interfacial chemistry for the aqueous batteries. [ABSTRACT FROM AUTHOR]

This work reports that a low‐temperature thermal calcination strategy was adopted to modulate the electronic structure and attain an abundance of surface‐active sites while maintaining the crystal morphology. All the experiments demonstrate that the new photocatalyst nano MIL‐125(Ti)‐250 obtained by thermal calcination strategy has abundant Ti3+ induced by oxygen vacancies and high specific surface area. This facilitates the adsorption and activation of N2 molecules on the active sites in the photocatalytic nitrogen fixation. The photocatalytic NH3 yield over MIL‐125(Ti)‐250 is enhanced to 156.9 μmol g−1 h−1, over twice higher than that of the parent MIL‐125(Ti) (76.2 μmol g−1 h−1). Combined with density function theory (DFT), it shows that the N2 adsorption pattern on the active sites tends to be from "end‐on" to "side‐on" mode, which is thermodynamically favourable. Moreover, the electrochemical tests demonstrate that the high atomic ratio of Ti3+/Ti4+ can enhance carrier separation, which also promotes the efficiency of photocatalytic N2 fixation. This work may offer new insights into the design of innovative photocatalysts for various chemical reduction reactions. [ABSTRACT FROM AUTHOR]

This work reports that a low‐temperature thermal calcination strategy was adopted to modulate the electronic structure and attain an abundance of surface‐active sites while maintaining the crystal morphology. All the experiments demonstrate that the new photocatalyst nano MIL‐125(Ti)‐250 obtained by thermal calcination strategy has abundant Ti3+ induced by oxygen vacancies and high specific surface area. This facilitates the adsorption and activation of N2 molecules on the active sites in the photocatalytic nitrogen fixation. The photocatalytic NH3 yield over MIL‐125(Ti)‐250 is enhanced to 156.9 μmol g−1 h−1, over twice higher than that of the parent MIL‐125(Ti) (76.2 μmol g−1 h−1). Combined with density function theory (DFT), it shows that the N2 adsorption pattern on the active sites tends to be from "end‐on" to "side‐on" mode, which is thermodynamically favourable. Moreover, the electrochemical tests demonstrate that the high atomic ratio of Ti3+/Ti4+ can enhance carrier separation, which also promotes the efficiency of photocatalytic N2 fixation. This work may offer new insights into the design of innovative photocatalysts for various chemical reduction reactions. [ABSTRACT FROM AUTHOR]

Quorum sensing (QS) serves as a vital means of intercellular signalling in a variety of prokaryotes, which enables single cells to act in multicellular configurations. The potential to control community‐wide responses has also sparked numerous recent biotechnological innovations. However, our capacity to utilize intercellular communication is hindered due to a scarcity of complementary signalling systems and a restricted comprehension of interconnections between these systems caused by variations in their dynamic range. In this study, we utilize uniform manifold approximation and projection and extended‐connectivity fingerprints to explore the available chemical space of QS signalling molecules. We investigate and experimentally characterize a set of closely related QS signalling ligands, consisting of N‐acyl homoserine lactones and the aryl homoserine lactone p‐coumaroyl, as well as a set of more widely diverging QS ligands, consisting of photopyrones, dialkylresorcinols, 3,5‐dimethylpyrazin‐2‐ol and autoinducer‐2, and define their performance. We report on a set of six signal‐ and promoter‐orthogonal intercellular QS signalling systems, significantly expanding the toolkit for engineering community‐wide behaviour. Furthermore, we demonstrate that ligand diversity can serve as a statistically significant tool to predict much more complicated ligand‐receptor interactions. This approach highlights the potential of dimensionality reduction to explore chemical diversity in microbial dynamics. [ABSTRACT FROM AUTHOR]

Quorum sensing (QS) serves as a vital means of intercellular signalling in a variety of prokaryotes, which enables single cells to act in multicellular configurations. The potential to control community‐wide responses has also sparked numerous recent biotechnological innovations. However, our capacity to utilize intercellular communication is hindered due to a scarcity of complementary signalling systems and a restricted comprehension of interconnections between these systems caused by variations in their dynamic range. In this study, we utilize uniform manifold approximation and projection and extended‐connectivity fingerprints to explore the available chemical space of QS signalling molecules. We investigate and experimentally characterize a set of closely related QS signalling ligands, consisting of N‐acyl homoserine lactones and the aryl homoserine lactone p‐coumaroyl, as well as a set of more widely diverging QS ligands, consisting of photopyrones, dialkylresorcinols, 3,5‐dimethylpyrazin‐2‐ol and autoinducer‐2, and define their performance. We report on a set of six signal‐ and promoter‐orthogonal intercellular QS signalling systems, significantly expanding the toolkit for engineering community‐wide behaviour. Furthermore, we demonstrate that ligand diversity can serve as a statistically significant tool to predict much more complicated ligand‐receptor interactions. This approach highlights the potential of dimensionality reduction to explore chemical diversity in microbial dynamics. [ABSTRACT FROM AUTHOR]

The competition between the ytterbium endo‐atom and the pyridine exo‐molecules as nucleophiles interacting with the electron‐deficient 1H,4H‐1,4‐diborabuckminsterfullerene was studied using the quantum chemical DFT PBE0 method. The equilibrium structural parameters, dipole moments, IR spectra, and exothermic effects of the formation of the C58B2•Py2 adduct and the endohedral Yb@C58B2•Py2 complex were determined. The concept of the state of oxidation/reduction of an atom in a chemical compound has been clarified. The localization of the ytterbium(II) under a pair of equivalent carbon atoms bonded to boron(III) atoms is predicted. The introduction of ytterbium(II) into the adduct cavity weakens exo‐bonds with pyridine molecules without changing the oxidation state of boron(III). Each nitrogen atom retains a lone electron pair, coordinated by a boron(III). The ytterbium(II) endo‐atom retains 14 electrons in f states. [ABSTRACT FROM AUTHOR]

This paper explores the interaction of divalent [Sm(DippForm)2(thf)2] with substrates containing azo linkages. Treatment of [Sm(DippForm)2(thf)2] with trans‐azobenzene results in formation of mononuclear [Smlll(DippForm)2(Ph2N2)(thf)] ⋅ 3THF (1) or dinuclear [Smlll(DippForm)(Ph2N2)(thf)]2 ⋅ 4THF (2) and [Sm(DippForm)3] depending on the reaction stoichiometry, where azobenzene has undergone either a one or two electron reduction. These reactions parallel the corresponding reactions of [Sm(C5Me5)2(thf)2], but the coordination of [N2Ph2]− in 1 differs significantly from that of {Sm(C5Me5)2(Ph2N2)(thf)}. On the other hand, the structure of 2 is similar to that of the pentamethylcyclopentadienyl analogue. The reaction of [Sm(DippForm)2(thf)2] with 1H‐1,2,3‐benzotriazole also yielded a trivalent samarium complex containing benzotriazolate (btz), [Smlll(DippForm)2(btz)(thf)] ⋅ THF (3), and suggests more utilization of 1H‐1,2,3‐benzotriazole in divalent lanthanoid reduction chemistry is possible. [ABSTRACT FROM AUTHOR]

A low‐cost plasma‐chemical hybrid process (PCHP) is proposed for simultaneous NOx and SOx treatment. PCHP can be integrated into existing desulfurization reactors by combining plasma oxidation and chemical reduction. PCHP is applied to glass melting furnace emissions with limited denitration technology, achieving higher removal efficiencies of NO, NOx, and SO2 (43%, 38%, and 28%, respectively) by optimizing reductant spray and installation angles. PCHP also improves fuel consumption, with a 0.04 increase in air ratio reducing energy consumption by 3.6 kL/day (equivalent to 6.6 t(CO2)/day reduction). In addition, PCHP allows for the collection and reuse of treated SO2 as sodium sulfate particles, making it a suitable aftertreatment technology for glass manufacturing exhaust. [ABSTRACT FROM AUTHOR]

Merino wool, a highly abundant natural fabric, was successfully transformed into a valuable substrate for preparing easily recoverable catalyst materials by depositing gold nanoparticles (AuNPs) through a series of modification steps. The functionality of wool was enhanced by cleaving‐SH groups using NaHS chemical reduction. Subsequently, the reduced wool keratin (WSH) was covalently attached to 3‐amino thiophenol (3‐ATP) or 4‐amino thiophenol (4‐ATP) monomers via S−S linkages. The surface was further modified by grafting P3ATP or P4ATP through oxidative polymerization of 3‐ATP or 4‐ATP using ammonium persulfate as an oxidant. Finally, AuNPs were deposited onto the P3ATP or P4ATP‐grafted wool (P3ATP‐g‐WSH or P4ATP‐g‐WSH) by immersing the samples in an aqueous HAuCl4 solution. Additionally, P3ATP or P4ATP‐coated composites (P3ATP/WSH or P4ATP/WSH) were prepared to assess the AuNP formation ability of the grafting. The structural and morphological changes occurred in the wool, and the presence of AuNPs was revealed by ATR‐FTIR, XPS, SEM, and contact angle. The catalytic performance of the AuNP‐containing composites in reducing various nitroarenes to aminoarenes using an excess of electron‐donor (NaBH4) was monitored by UV‐vis spectroscopy. The developed composites demonstrated high efficiency, reusability, and rapid catalytic activity, achieving the highest apparent rate constant of 3.79 min−1, even within 1 min. [ABSTRACT FROM AUTHOR]

The reaction of benzoborirene with one equivalent of isocyanides leads to benzene‐fused boretes bearing one imine function, while the reaction with two equivalents of isocyanide affords 2,3‐dihydro‐2,3‐diiminoboroles with perfect regioselectivity. The isocyanide double insertion products represent a novel type of 1,2‐diimine with a benzoborole backbone. The reduction chemistry of the benzoborole‐supported 1,2‐diimine was investigated. Single‐ and two‐electron reduction allow for the isolation and full characterization of a radical anion and a dianion, respectively. In stark contrast to the ordinary boroles, which should turn aromatic by accepting two electrons, the antiaromatic character of the benzoborole backbone is highlighted upon reduction, thus presenting a rare example of antiaromatic borole dianion. Detailed quantum chemical calculations provide a rationale for the observed regioselectivity and the electronic structure of the reduced borole diimine species. [ABSTRACT FROM AUTHOR]

Constructing a stable solid electrolyte interphase (SEI) at the electrode–electrolyte interface is powerful for optimizing the battery performance. However, studies related to interface chemistry have particularly focused on engineering electrolytes and overlooked regulating electrode materials. Here, this study reports that the B‐doped Bi interconnected nanoparticles (B─Bi) are prepared by a facile and effective chemical reduction reaction. The B doping helps to catalyze the electrolyte decomposition and more NaF formation on the electrode surface, which facilitates a stable uniform SEI with enhanced mechanical stability. Such a robust SEI layer can inhibit the further decomposition of electrolytes and promote the interfacial Na+ transfer. The B─Bi offers a reversible capacity of 403.1 mAh g−1 at 1.0 A g−1 and a high rate capability of 203 mAh g−1 at 80 A g−1. Moreover, the B‐doping method also finds its viability to stabilize SEI in Sb material. This study demonstrates a new strategy for engineering the interface chemistry toward stable SEI and excellent performance. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction reaction (CO2RR) over Cu catalysts exhibits enormous potential for efficiently converting CO2 to ethylene (C2H4). However, achieving high C2H4 selectivity remains a considerable challenge due to the propensity of Cu catalysts to undergo structural reconstruction during CO2RR. Herein, we report an in situ molecule modification strategy that involves tannic acid (TA) molecules adaptive regulating the reconstruction of a Cu‐based material to a pathway that facilitates CO2 reduction to C2H4 products. An excellent Faraday efficiency (FE) of 63.6 % on C2H4 with a current density of 497.2 mA cm−2 in flow cell was achieved, about 6.5 times higher than the pristine Cu catalyst which mainly produce CH4. The in situ X‐ray absorption spectroscopy and Raman studies reveal that the hydroxyl group in TA stabilizes Cuδ+ during the CO2RR. Furthermore, theoretical calculations demonstrate that the Cuδ+/Cu0 interfaces lower the activation energy barrier for *CO dimerization, and hydroxyl species stabilize the *COH intermediate via hydrogen bonding, thereby promoting C2H4 production. Such molecule engineering modulated electronic structure provides a promising strategy to achieve highly selective CO2 reduction to value‐added chemicals. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction reaction (CO2RR) over Cu catalysts exhibits enormous potential for efficiently converting CO2 to ethylene (C2H4). However, achieving high C2H4 selectivity remains a considerable challenge due to the propensity of Cu catalysts to undergo structural reconstruction during CO2RR. Herein, we report an in situ molecule modification strategy that involves tannic acid (TA) molecules adaptive regulating the reconstruction of a Cu‐based material to a pathway that facilitates CO2 reduction to C2H4 products. An excellent Faraday efficiency (FE) of 63.6 % on C2H4 with a current density of 497.2 mA cm−2 in flow cell was achieved, about 6.5 times higher than the pristine Cu catalyst which mainly produce CH4. The in situ X‐ray absorption spectroscopy and Raman studies reveal that the hydroxyl group in TA stabilizes Cuδ+ during the CO2RR. Furthermore, theoretical calculations demonstrate that the Cuδ+/Cu0 interfaces lower the activation energy barrier for *CO dimerization, and hydroxyl species stabilize the *COH intermediate via hydrogen bonding, thereby promoting C2H4 production. Such molecule engineering modulated electronic structure provides a promising strategy to achieve highly selective CO2 reduction to value‐added chemicals. [ABSTRACT FROM AUTHOR]

We report the formation of a NpIV complex from the complexation of NpVIO22+ with the redox‐active ligand tBu‐pdiop2−=2,6‐bis[N‐(3,5‐di‐tert‐butyl‐2‐hydroxyphenyl)iminomethyl]pyridine. To the best of our knowledge, this is the first example of the direct complexation‐induced chemical reduction of NpVIO22+ to NpIV. In contrast, the complexation of UVIO22+ with tBu‐pdiop2− did not induce the reduction of UVIO22+, not even after the two‐electron electrochemical reduction of [UVIO2(tBu‐pdiop)]. This contrast between the Np and U systems may be ascribed to the decrease of the energy of the 5 f orbitals in Np compared to those in U. The present findings indicate that the redox chemistry between UVIO22+ and NpVIO22+ should be clearly differentiated in redox‐active ligand systems. [ABSTRACT FROM AUTHOR]

Autocatalytic reactions were proposed to play a key role at the beginning of life starting from the first reduction of CO2 to formate, acetate and C1−C4 hydrocarbons. In carbon capture and utilization (CCU) processes, the same reactions were demonstrated to be autocatalytic and, in some cases, promoted by catalysts of the same composition. Through evolution, CO2 reduction then turned into complex autocatalytic networks such as photosynthesis, where CCU chemists found inspiration for the development of more advanced systems for the synthesis of value‐added chemicals. Less evolved systems than photosynthesis, however, may be easier to emulate and provide valuable inspiration into CO2 reduction chemistry for CCU. Other synthetic systems were also demonstrated to be autocatalytic demonstrating that CO2 reactions and autocatalysis are closely connected. In this concept article, the relationship between natural, artificial and bio‐inspired autocatalytic CO2 reduction processes is summarized and discussed. The accomplishments resulting from the integration of autocatalysis and CCU strategies, along with their inherent benefits and future prospectives are also outlined. [ABSTRACT FROM AUTHOR]

In this study, a new concept of physical unclonable functions (PUFs) is introduced comprising reduced graphene oxide (GO) materials. To create a disordered conductivity distribution, two types of GO are used: HGO, are produced by the conventional Hummers' method, and PGO, produced by Brodie's method with an additional unique purification procedure. It is found that PGO becomes graphene-like after room-temperature chemical reduction. These two reduced GOs have a distinct conductivity difference of up to 104 times. By blending these two materials, a random mixture is created that can generate a highly unpredictable electrical signal, serving as an ideal security key with strong randomness and uniqueness. The optimized PUF device, based on this approach, demonstrates excellent performance in generating secure keys. [ABSTRACT FROM AUTHOR]

Carbon use efficiency (CUE) is being intensively applied to quantify carbon (C) cycling processes from microbial cell to global scales. Energy use efficiency (EUE) is at least as important as the CUE because (i) microorganisms use organic C mainly as an energy source and not as elemental C per se, and (ii) microbial growth and maintenance are limited by energy, but not by C as a structural element. We conceptualize and review the importance of EUE by soil microorganisms and focus on (i) the energy content in organic compounds depending on the nominal oxidation state of carbon (NOSC), (ii) approaches to assess EUE, (iii) similarities and differences between CUE and EUE, and (iv) discuss mechanisms responsible for lower EUE compared to CUE. The energy content per C atom (enthalpy of combustion, the total energy stored in a compound) in organic compounds is very closely (R2 = 0.98) positively related to NOSC and increases by 108 kJ mol−1 C per one NOSC unit. For the first time we assessed the NOSC of microbial biomass in soil (−0.52) and calculated the corresponding energy content of −510 kJ mol−1 C. We linked CUE and EUE considering the NOSC of microbial biomass and element compositions of substrates utilized by microorganisms. The mean microbial EUE (0.32–0.35) is 18% lower than CUE (0.41) using glucose as a substrate. This definitely indicates that microbial growth is limited by energy relative to C. Based on the comparison of a broad range of processes of C and energy utilization for cell growth and maintenance, as well as database of experimental CUE from various compounds, we clearly explained five mechanisms and main factors why EUE is lower than CUE. The two main mechanisms behind lower EUE versus CUE are: (i) microbial recycling: C can be microbially recycled, whereas energy is always utilized only once, and (ii) chemical reduction of organic and inorganic compounds: Energy is used for reduction, which is ongoing without C utilization. [ABSTRACT FROM AUTHOR]

The complex [Mn(bpy)(CO)3Br], has been previously studied as both an electrocatalyst and a photocatalyst, in conjugation with a photosensitizer, for CO2 reduction to CO. This study considers the relationship between this catalytic activity and the steric and electronic nature of the aromatic diimine ligand. To this end, the π‐system in the bidentate ligand is increased step‐wise from 2,2′‐bipyridine (bpy) to 2‐(2‐pyridyl)quinoline (pq) to 2,2′‐biquinoline (bqn) in a series of three fac‐[Mn(α‐diimine)(CO)3Br] complexes. It is found that the propensity of these complexes to photochemically dimerize trends with the energy of the α‐diimine π* energy. Electrochemically, it is observed that the second reduction event in these systems becomes increasingly thermodynamically favorable and approaches the potential of the first reduction event as the π‐system expands. In fac‐[Mn(bqn)(CO)3Br], the second reduction is more favorable than the first reduction, precluding the formation of a dimer intermediate; even though, chemical reduction of fac‐[Mn(bqn)(CO)3Br] confirms that the dimer, [Mn(bqn)(CO)3Br]2 is able to form and not prevented by steric considerations. Though the second reduction potential is more positive for bqn and pq than for bpy, the CO2 reduction mechanism changes such that the overpotential for carbon dioxide reduction occurs at more negative potentials, leading to a decrease in overall catalytic activity. [ABSTRACT FROM AUTHOR]

The detection of trace microRNAs (miRNA) is crucial for early cancer diagnosis. Here, a sensitive biosensor for miRNA directive detection was put forward, which was based on RNA‐templated palladium nanoparticles (PdNPs) signal amplification strategy. Uncharged peptide nucleic acids (PNA) probe was used to capture the target miRNA(T‐RNA) specifically. Subsequently, a large amount of palladium ions absorbed on T‐RNA strands via electrostatic forces, and the palladium nanocluster is rapidly generated based on chemical reduction. Obviously, RNA metallization method enables biosensor to be carried out efficiently at room temperature also simplifies the preparation and detection of the sensor. Under optimal conditions, this method can analyze the concentration of miRNA in the range of 10 fM to 1 nM, and the detection limit is 3.33 fM. At the same time, this method has strong anti‐interference ability in serum samples, which provides a broad prospect for the early screening and diagnosis of cancer. [ABSTRACT FROM AUTHOR]

Upgrading cyclohexanone to ϵ‐caprolactone (ϵ‐CL) is of great importance to the synthesis of high value‐added downstream chemicals and the reduction of foam plastic. The catalytic synthesis of ϵ‐CL from cyclohexanone through O2/aldehyde method is an environmentally benign one‐pot tandem reaction without using peroxy acid, balancing the requirements of safety and efficiency. However, due to lack of elaborate design and collaboration of multiple active sites for catalysts, the catalytic efficiency of O2/aldehyde method still remains to be improved. Herein, a pitaya‐like catalyst (CeFe@RDC‐3) with Ce and Fe highly dispersed on resin‐derived‐carbon is synthesized through high temperature self‐assembly. On this bimetallic catalyst, high yield (97 %) of ϵ‐CL is achieved through aerobic oxidation of cyclohexanone with only 1.5 equivalent benzaldehyde. Moreover, considerable yields of ϵ‐CL, 88.3 % and 74.7 %, respectively, are also obtained over CeFe@RDC‐3 with green solvent (EtOAc) or even without solvent. No loss of activity is observed after five successive cycles, demonstrating high stability of CeFe@RDC‐3. The mechanism study reveals that the high performance of CeFe@RDC‐3 is ascribed to the Ce−Fe bimetallic synergy, uniform metal dispersion, abundant active oxygen and stabilizing effect of resin‐derived‐carbon to free radicals. This work provides prospect for a green, safe and low‐cost strategy for Baeyer‐Villiger process. [ABSTRACT FROM AUTHOR]

Massive efforts are invested in developing innovative CO2‐sequestration strategies to counter climate change and transform CO2 into higher‐value products. CO2‐capture by reduction is a chemical challenge, and attention is turned toward biological systems that selectively and efficiently catalyse this reaction under mild conditions and in aqueous solvents. While a few reports have evaluated the effectiveness of isolated bacterial formate dehydrogenases as catalysts for the reversible electrochemical reduction of CO2, it is imperative to explore other enzymes among the natural reservoir of potential models that might exhibit higher turnover rates or preferential directionality for the reductive reaction. Here, we present electroenzymatic catalysis of formylmethanofuran dehydrogenase, a CO2‐reducing‐and‐fixing biomachinery isolated from a thermophilic methanogen, which was deposited on a graphite rod electrode to enable direct electron transfer for electroenzymatic CO2 reduction. The gas is reduced with a high Faradaic efficiency (109±1 %), where a low affinity for formate prevents its electrochemical reoxidation and favours formate accumulation. These properties make the enzyme an excellent tool for electroenzymatic CO2‐fixation and inspiration for protein engineering that would be beneficial for biotechnological purposes to convert the greenhouse gas into stable formate that can subsequently be safely stored, transported, and used for power generation without energy loss. [ABSTRACT FROM AUTHOR]

Massive efforts are invested in developing innovative CO2‐sequestration strategies to counter climate change and transform CO2 into higher‐value products. CO2‐capture by reduction is a chemical challenge, and attention is turned toward biological systems that selectively and efficiently catalyse this reaction under mild conditions and in aqueous solvents. While a few reports have evaluated the effectiveness of isolated bacterial formate dehydrogenases as catalysts for the reversible electrochemical reduction of CO2, it is imperative to explore other enzymes among the natural reservoir of potential models that might exhibit higher turnover rates or preferential directionality for the reductive reaction. Here, we present electroenzymatic catalysis of formylmethanofuran dehydrogenase, a CO2‐reducing‐and‐fixing biomachinery isolated from a thermophilic methanogen, which was deposited on a graphite rod electrode to enable direct electron transfer for electroenzymatic CO2 reduction. The gas is reduced with a high Faradaic efficiency (109±1 %), where a low affinity for formate prevents its electrochemical reoxidation and favours formate accumulation. These properties make the enzyme an excellent tool for electroenzymatic CO2‐fixation and inspiration for protein engineering that would be beneficial for biotechnological purposes to convert the greenhouse gas into stable formate that can subsequently be safely stored, transported, and used for power generation without energy loss. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction to value‐added chemicals or fuels offers a promising approach to reduce carbon emissions and alleviate energy shortage. Cu‐based electrocatalysts have been widely reported as capable of reducing CO2 to produce a variety of multicarbon products (e.g. ethylene and ethanol). In this work, we develop sulfur‐doped Cu2O electrocatalysts, which instead can electrochemically reduce CO2 to almost exclusively formate. We show that a dynamic equilibrium of S exists at the Cu2O‐electrolyte interface, and S‐doped Cu2O undergoes in situ surface reconstruction to generate active S‐adsorbed metallic Cu sites during the CO2 reduction reaction (CO2RR). Density functional theory (DFT) calculations together with in situ infrared absorption spectroscopy measurements show that the S‐adsorbed metallic Cu surface can not only promote the formation of the *OCHO intermediate but also greatly suppress *H and *COOH adsorption, thus facilitating CO2‐to‐formate conversion during the electrochemical CO2RR. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction to value‐added chemicals or fuels offers a promising approach to reduce carbon emissions and alleviate energy shortage. Cu‐based electrocatalysts have been widely reported as capable of reducing CO2 to produce a variety of multicarbon products (e.g. ethylene and ethanol). In this work, we develop sulfur‐doped Cu2O electrocatalysts, which instead can electrochemically reduce CO2 to almost exclusively formate. We show that a dynamic equilibrium of S exists at the Cu2O‐electrolyte interface, and S‐doped Cu2O undergoes in situ surface reconstruction to generate active S‐adsorbed metallic Cu sites during the CO2 reduction reaction (CO2RR). Density functional theory (DFT) calculations together with in situ infrared absorption spectroscopy measurements show that the S‐adsorbed metallic Cu surface can not only promote the formation of the *OCHO intermediate but also greatly suppress *H and *COOH adsorption, thus facilitating CO2‐to‐formate conversion during the electrochemical CO2RR. [ABSTRACT FROM AUTHOR]

The performance of perovskite solar cells (PSCs) is negatively affected by iodine (I2) impurities generated from the oxidation of iodide ions in the perovskite precursor powder, solution, and perovskite films. In this study, the use of potassium formate (HCOOK) as a reductant to minimize the presence of detrimental I2 impurities is presented. It is demonstrated that HCOOK can effectively reduce I2 back to I− in the precursor solution as well as in the devices under external conditions. Furthermore, the introduced formate anion (HCOO−) and alkali metal cation (K+) can reduce the defect density within the perovskite film by modulating perovskite growth and passivating electronic defects, significantly prolonging the carrier lifetime and reducing the J–V hysteresis. Consequently, the maximum efficiency of the HCOOK‐doped planar n–i–p PSCs reaches 23.8%. After 1000 h of operation at maximum power point tracking under continuous 1 sun illumination, the corresponding encapsulated devices retain 94% of their initial efficiency. [ABSTRACT FROM AUTHOR]

The efficient conversion of CO2 to value‐added products represents one of the most attractive solutions to mitigate climate change and tackle the associated environmental issues. In particular, electrochemical CO2 reduction to fuels and chemicals has garnered tremendous interest over the last decades. Among all products from CO2 reduction, formic acid is considered one of the most economically vital CO2 reduction products. P‐block metals (especially Bi, Sn, In, and Pb) have been extensively investigated and recognized as the most efficient catalytic materials for the CO2 electroreduction to formate. Despite remarkable progress, the future implementation of this technology at the industrial‐scale hinges on the ability to solve remaining roadblocks. In this review, the current research status, challenges, and prospects of p‐block metal‐based catalysts primarily for CO2 electroreduction to formate are comprehensively reviewed. The rational design and nanostructure engineering of these p‐block metal catalysts for the optimization of their electrochemical performances are discussed in detail. Subsequently, the recent progress in the development of state‐of‐the‐art operando characterization techniques together with the design of advanced electrochemical cells to uncover the intrinsic catalysis mechanism is discussed. Lastly, a perspective on future directions including tackling critical challenges to realize its early industrial implementation is presented. [ABSTRACT FROM AUTHOR]

In recent years, single‐atom catalysts (SACs) have received increasing attention in the field of electrochemical CO2RR with their efficient atom utilization efficiency and excellent catalytic performance. However, their low metal loading and the presence of linear relationships for single active sites with simple structures possibly restrict their activity and practical applications. Active site tailoring at the atomic level is a visionary approach to break the existing limitations of SACs. This paper first briefly introduces the synthesis strategies of SACs and DACs. Then, combining previous experimental and theoretical studies, this paper introduces four optimization strategies, namely spin‐state tuning engineering, axial functionalization engineering, ligand engineering, and substrate tuning engineering, for improving the catalytic performance of SACs in the electrochemical CO2RR process by combining previous experimental and theoretical studies. Then it is introduced that DACs exhibit significant advantages over SACs in increasing metal atom loading, promoting the adsorption and activation of CO2 molecules, modulating intermediate adsorption, and promoting C−C coupling. At the end of this paper, we briefly and succinctly summarize the main challenges and application prospects of SACs and DACs in the field of electrochemical CO2RR at present. [ABSTRACT FROM AUTHOR]

Soil density fractionation is a common tool to separate organic matter of different function and turnover. But it has not been tested so far how much soil material is necessary to obtain reproducible results. A reduction of chemicals like polytungstate would further save valuable resources. Here, we show that soil weight reduction from 25 to 5 g was not significantly affecting fractionation results. Compared to the commonly used 10–25 g, this corresponds to a saving of resources of up to 80%. [ABSTRACT FROM AUTHOR]

Introduction: Non‐small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation has a higher incidence of brain metastases than wild‐type EGFR mutations. Osimertinib, a third‐generation EGFR tyrosine kinase inhibitor (TKI), targets both EGFR‐TKI sensitizing and T790M‐resistance mutations and has a higher brain penetration rate relative to first‐ and second‐generation EGFR‐TKIs. Therefore, osimertinib has become a preferred first‐line therapy for advanced EGFR mutation‐positive NSCLC. However, lazertinib, an emerging EGFR‐TKI, has shown higher selectivity toward EGFR mutations and improved penetration of the blood–brain barrier compared to osimertinib in preclinical studies. This trial will evaluate the efficacy of lazertinib as a first‐line therapy in patients with EGFR mutation‐positive NSCLC who have brain metastases, with or without additional local therapy. Methods: This is a single‐center, open‐label, single‐arm phase II trial. A total of 75 patients with advanced EGFR mutation‐positive NSCLC will be recruited. Eligible patients will receive oral lazertinib 240 mg, once daily until disease progression or intolerable toxicity is detected. Patients with moderate to severe symptoms related to brain metastasis will simultaneously receive local therapy for the brain. The primary endpoints are progression‐free survival and intracranial progression‐free survival. Discussion: Lazertinib, in combination with local therapy for the brain, if necessary, is expected to improve the clinical benefit in advanced EGFR mutation‐positive NSCLC with brain metastases, as a first‐line treatment. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 into chemical feedstocks has been regarded as an attractive way to reconstruct the carbon cycle. In this work, nitrogen‐doped carbon was prepared by high temperature pyrolysis using polydopamine (PDA) microspheres as precursors. The effects of doped nitrogen units, surface hydrophilicity and pore structures of the N‐Carbon catalysts on the CO2 reduction reaction (CO2RR) activities were systematically investigated. It was demonstrated that the competition between the hydrogen evolution reaction (HER) and the CO2RR under reduction potentials was modified by the nature of surface hydrophilicity/hydrophobicity and the doped nitrogen units. The CO2RR activities were further optimized via the pore structures regulation. Results showed that pore structure with size below 1 nm was favorable for CO2RR and the developed N‐Carbon catalysts with optimized nitrogen units, hydrophilicity, and pore structure achieved a high CO2 to CO Faradaic efficiency of 95 % in the H‐cell. [ABSTRACT FROM AUTHOR]

A novel nanocomposite (TNTs‐FeS) was developed by anchoring ferrous sulfide (FeS) nanoparticles immobilized on titanate nanotubes (TNTs) by hydrothermal method to remove U(VI) and Re(VII) from aqueous solution, and the removal mechanism and efficiency were examined. The experimental results showed that the TNTs can effectively improve the dispersibility and stability of FeS. The environmental conditions, including initial solution pH, initial concentration, equilibrium time, and dosage, played an important role in the remediation process, which can affect the immobilization efficiency significantly. The maximum quantity removal of U(VI) and Re(VII) was 291.67 and 226.23 mg/g at pH of 6.0 and 12.0. The adsorption kinetics and the equilibrium isotherms of U(VI) and Re(VII) all fitted well with the pseudo‐second‐order model (R2>0.99) and the Freundlich model (R2>0.99). The main mechanism of removal by TNTs‐FeS was electrostatic attraction, chemical reduction, and surface complexation. Thus, TNTs‐FeS composites exhibited a high potential to remove U(VI) and Re(VII) heavy metal ions from the surface and groundwater. [ABSTRACT FROM AUTHOR]

Excess CO2 can be effectively converted into valuable fuels and chemicals by electrochemical CO2 reduction, which can help establish a low‐carbon emission economy and solve the current energy crisis. In recent years, metal‐organic frameworks (MOFs), as an emerging multifunctional material with porous structure, high chemical tunability and large specific surface area, has received increasing attention in the field of electrochemical CO2RR. In this paper, we present a comprehensive overview of various MOFs and their derivatives as CO2RR electrocatalysts and analyze their roles in the catalytic process from physical and chemical aspects. In addition, combining experiments and theory, this article also offers a personal view on the electronic structure modulation strategies to improve electrocatalytic performance. The article concludes with an analysis of the challenges in realizing MOFs and their derivatives for electrocatalytic CO2RR applications. [ABSTRACT FROM AUTHOR]

In this study, silver‐titanium dioxide/graphene aerogel (Ag−TiO2/GA−ATG) was synthesized via chemical reduction using ethylene diamine (EDA). The effects of reductant doses on the formation of the three‐dimensional structure and the photocatalytic degradation efficiency of ATG were evaluated with five different volumes (20, 30, 40, 50, and 60 μL), corresponding to the ATG1, ATG2, ATG3, and ATG4, respectively. The results showed that 40 μL of EDA was the suitable condition for the formation of ATG three‐dimensional structure. Characterizations revealed that ATG3 was successfully synthesized with distinctive peaks of Ag and TiO2 in the X‐ray diffraction patterns whilst scanning electron microscope and high resolution transmission electron microscope images showed a porous structure, silver nanoparticles and TiO2 with an average size of 10–25 nm were uniformly distributed on the graphene surface. Furthermore, ATG3 possessed the highest photocatalytic capability to deteriorate methyl orange with an efficiency of up to 99.53 % with a catalyst dose of 0.3 mg/mL, superior compared to those of TiO2 and TiO2/GA. The radicals scavenging experiments elucidated ⋅O2 ${{{\rm { O}}}_{{\rm { 2}}}^{{\rm { \char60 M-\char62 }}}}$ to majorly contribute to the photodegradation process. Moreover, ATG3 showed high recyclability, which retains 80 % of yield even after 10 cycles. Those findings proved that ATG has high potential in the environmental remediation field. [ABSTRACT FROM AUTHOR]

Rationale: Shiga toxin‐producing Escherichia coli (STEC) are an ongoing threat to public health and agriculture. Our laboratory has developed a rapid method for identification of Shiga toxin (Stx), bacteriophage, and host proteins produced from STEC. We demonstrate this technique on two genomically sequenced STEC O145:H28 strains linked to two major outbreaks of foodborne illness occurring in 2007 (Belgium) and 2010 (Arizona). Methods: Our approach was to induce expression of stx, prophage, and host genes by antibiotic exposure, chemically reduce samples, and identify protein biomarkers from unfractionated samples using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, tandem mass spectrometry (MS/MS), and post‐source decay (PSD). The protein mass and prominent fragment ions were used to identify protein sequences using top‐down proteomic software developed in‐house. Prominent fragment ions are the result of polypeptide backbone cleavage resulting from the aspartic acid effect fragmentation mechanism. Results: The B‐subunit of Stx and acid‐stress proteins HdeA and HdeB were identified in both STEC strains in their intramolecular disulfide bond‐intact and reduced states. In addition, two cysteine‐containing phage tail proteins were detected and identified from the Arizona strain but only under reducing conditions, which suggests that bacteriophage complexes are bound by intermolecular disulfide bonds. An acyl carrier protein (ACP) and a phosphocarrier protein were also identified from the Belgium strain. ACP was post‐translationally modified with attachment of a phosphopantetheine linker at residue S36. The abundance of ACP (plus linker) was significantly increased on chemical reduction, suggesting the release of fatty acids bound to the ACP + linker at a thioester bond. MS/MS‐PSD revealed dissociative loss of the linker from the precursor ion as well as fragment ions with and without the attached linker consistent with its attachment at S36. Conclusions: This study demonstrates the advantages of chemical reduction in facilitating the detection and top‐down identification of protein biomarkers of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

A small macrocycle comprising ether‐bridged naphthyl units was prepared in a two‐step synthesis. Single‐crystal X‐ray diffraction of two polymorphs are reported, one of which showed multiple C−H⋅⋅⋅πnaphthyl interactions of a solvent molecule in the cavity of the macrocycle. Chemical reduction led to C−O bond cleavages accompanied by a Z/E isomerization. The resulting twofold negatively charged (E)‐1,2‐bis(2‐naphthyl)ethylene fragment was isolated as its potassium salts. Electronic characterization revealed a singlet ground state, and a marked distortion of the central ethylene unit was observed upon electron uptake. [ABSTRACT FROM AUTHOR]

In this study, a novel strategy to amplify electrochemical signals by mesoporous PdPt nanoparticles with core‐shell structures anchored on a three‐dimensional PANI@CNTs network as nanozyme labels (PdPt/PANI@CNTs) was proposed for the sensitive monitoring of α‐fetoprotein (AFP, Ag). First, the mesoporous PdPt nanoparticles prepared by a facile chemical reduction method had excellent biocompatibility with biomolecules, which could capture a large amount of AFP‐Ab2 (Ab2) and exhibit plentiful pores to entrap more thionine (Thi) into mesoporous PdPt nanoparticles with enhanced loading and abundant active sites. Furthermore, the resulting mesoporous PdPt nanoparticles were abundantly dotted on the surface of a three‐dimensional PANI@CNTs network with excellent conductivity and a high specific surface area through the bonding of the amino group to form PdPt/PANI@CNTs nanozyme labels. Most importantly, the as‐prepared PdPt/PANI@CNTs nanozyme labels exhibited unexpected enzyme‐like activity towards the reduction of hydrogen peroxide owing to the highly indexed facets, enhancing the current response to realize signal amplification. In view of the advantages of nanozyme labels and the involvement of gold nanoparticles (AuNPs, which behave as electrode materials) for the sensitive determination of AFP, the as‐developed immunosensor could obtain a dynamic working range of 0.001 ng mL−1–100.0 ng mL−1 at a detection limit of 0.33 pg mL−1 via DPV (at 3σ). Furthermore, the nanozyme‐based electrochemical immunosensor exhibited remarkable analytical performance, which brought about feasible ideas for disease diagnosis in the future. [ABSTRACT FROM AUTHOR]

The preparation of three different functionalized palladium nanoparticles (PdNPs) systems for room temperature BTX (benzene, toluene, p‐xylene) sensing detection and their morphostructural characterization is described. PdNPs are prepared through a two‐phase water/toluene wet chemical reduction method in the presence of bifunctional organic thiols as stabilizing agents suitable for the formation of covalently linked PdNPs networks: p‐terphenyl‐4,4″‐dithiol (PdNPs‐TR), biphenyl‐4,4′‐dithiol (PdNPs‐BP), or with 9,9‐didodecyl‐2,7‐bis(acetylthio)fluorene (PdNPs‐FL). Comparing the hydrodynamic diameter values, TR and BP ligands help to obtain networks consisting of spherical NPs of about 2 nm, in which each bifunctional ligand act as a bridge between PdNPs. In contrast, PdNPs‐FL show a population centered at <2RH> = 45 ± 5 nm. To perform preliminary gas sensing measurements, PdNPs networks are cast deposited on interdigitated electrodes to study their resistive response toward volatile organic compounds (VOCs) such as benzene (0–5%), toluene (0–1.7%), and p‐xylene (0–0.4%) (BTX) and common interfering gases (H2S, NH3, SO2, and relative humidity, RH). PdNPs‐FL show enhanced response to BTX with an appreciable response also toward H2S and RH. PdNPs‐TR exhibit a better ability to discriminate benzene gas with a negligible response after H2S exposure. Moreover, all the PdNPs systems show little to no response to NH3 and SO2 gases, offering an interesting perspective in practical sensing applications. [ABSTRACT FROM AUTHOR]

The syntheses and magnetic properties of organometallic heterometallic compounds [K(THF)6]{CoI[(μ3‐HAN)RE2Cp*4]2} (1‐RE) and [K(Crypt)]2{CoI[(μ3‐HAN)RE2Cp*4]2} (2‐RE) containing hexaazatrinaphthylene radicals (HAN⋅3−) and four rare earth (RE) ions are reported. 1‐RE shows isolable species with ligand‐based mixed valency as revealed by cyclic voltammetry (CV) thus leading to the isolation of 2‐RE via one‐electron chemical reduction. Strong electronic communication in mixed‐valency supports stronger overall ferromagnetic behaviors in 2‐RE than 1‐RE containing Gd and Dy ions. Ac magnetic susceptibility data reveal 1‐Dy and 2‐Dy both exhibit slow magnetic relaxation. Importantly, larger coercive field was observed in the hysteresis of 2‐Dy at 2.0 K, indicating the enhanced SMM behavior compared with 1‐Dy. Ligand‐based mixed‐valency strategy has been used for the first time to improve the magnetic coupling in lanthanide (Ln) SMMs, thus opening up new ways to construct strongly coupled Ln‐SMMs. [ABSTRACT FROM AUTHOR]

The syntheses and magnetic properties of organometallic heterometallic compounds [K(THF)6]{CoI[(μ3‐HAN)RE2Cp*4]2} (1‐RE) and [K(Crypt)]2{CoI[(μ3‐HAN)RE2Cp*4]2} (2‐RE) containing hexaazatrinaphthylene radicals (HAN⋅3−) and four rare earth (RE) ions are reported. 1‐RE shows isolable species with ligand‐based mixed valency as revealed by cyclic voltammetry (CV) thus leading to the isolation of 2‐RE via one‐electron chemical reduction. Strong electronic communication in mixed‐valency supports stronger overall ferromagnetic behaviors in 2‐RE than 1‐RE containing Gd and Dy ions. Ac magnetic susceptibility data reveal 1‐Dy and 2‐Dy both exhibit slow magnetic relaxation. Importantly, larger coercive field was observed in the hysteresis of 2‐Dy at 2.0 K, indicating the enhanced SMM behavior compared with 1‐Dy. Ligand‐based mixed‐valency strategy has been used for the first time to improve the magnetic coupling in lanthanide (Ln) SMMs, thus opening up new ways to construct strongly coupled Ln‐SMMs. [ABSTRACT FROM AUTHOR]

The photocatalytic CO2 reduction into value‐added chemicals is regarded as one promising technology to mitigate environmental issues and the energy crisis of the modern world due to the extended CO2 emissions. Recent advances have shown that iron porphyrins are considered as one of the most efficient molecular catalysts in the activation and reduction of molecules like CO2. Thus, a suitably modified FeIII porphyrin ([FeIII(TF4TMAP)](CF3SO3)5) was prepared and its catalytic activity in terms of photocatalytic reduction of CO2 was studied. This iron catalyst possesses four fluorine substituents in the ortho and the meta position of each meso‐phenyl group of the porphyrin, while trimethylammonium groups were placed in the para position. Photocatalytic studies were performed in the presence of an iridium complex as a chromophore and have shown that [FeIII(TF4TMAP)](CF3SO3)5 can effectively reduce CO2, achieving excellent turnover numbers (up to 5500 TONs) and high turnover frequencies. The main reduction product of this photocatalytic system was CO, and only a small amount of hydrogen was detected, presenting a maximum selectivity of 86 % for CO. [ABSTRACT FROM AUTHOR]