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The hydrazine oxidation‐assisted H2 evolution method promises low‐input and input‐free hydrogen production. However, developing high‐performance catalysts for hydrazine oxidation (HzOR) and hydrogen evolution (HER) is challenging. Here, we introduce a bifunctional electrocatalyst α‐MoC/N−C/RuNSA, merging ruthenium (Ru) nanoclusters (NCs) and single atoms (SA) into cubic α‐MoC nanoparticles‐decorated N‐doped carbon (α‐MoC/N−C) nanowires, through electrodeposition. The composite showcases exceptional activity for both HzOR and HER, requiring −80 mV and −9 mV respectively to reach 10 mA cm−2. Theoretical and experimental insights confirm the importance of two Ru species for bifunctionality: NCs enhance the conductivity, and its coexistence with SA balances the H ad/desorption for HER and facilitates the initial dehydrogenation during the HzOR. In the overall hydrazine splitting (OHzS) system, α‐MoC/N−C/RuNSA excels as both anode and cathode materials, achieving 10 mA cm−2 at just 64 mV. The zinc hydrazine (Zn−Hz) battery assembled with α‐MoC/N−C/RuNSA cathode and Zn foil anode can exhibit 97.3 % energy efficiency, as well as temporary separation of hydrogen gas during the discharge process. Therefore, integrating Zn−Hz with OHzS system enables self‐powered H2 evolution, even in hydrazine sewage. Overall, the amalgamation of NCs with SA achieves diverse catalytic activities for yielding multifold hydrogen gas through advanced cell‐integrated‐electrolyzer system. [ABSTRACT FROM AUTHOR]

Zeolite synthesis under acidic conditions has always presented a challenge. In this study, we successfully prepared series of ZSM‐5 zeolite nanosheets (Z‐5‐SCA‐X) over a broad pH range (4 to 13) without the need for additional supplements. This achievement was realized through aggregation crystallization of ZSM‐5 zeolite subcrystal (Z‐5‐SC) with highly short‐range ordering and ultrasmall size extracted from the synthetic system of ZSM‐5 zeolite. Furthermore, the crystallization behavior of Z‐5‐SC was investigated, revealing its non‐classical crystallization process under mildly alkaline and acidic conditions (pH<10), and the combination of classical and non‐classical processes under strongly alkaline conditions (pH≥10). What's particularly intriguing is that, the silanol nest content in the resultant Z‐5‐SCA‐X samples appears to be dependent on the pH values during the Z‐5‐SC crystallization process rather than its crystallinity. Finally, the results of the furfuryl alcohol etherification reaction demonstrate that reducing the concentration of silanol nests significantly enhances the catalytic performance of the Z‐5‐SCA‐X zeolite. The ability to synthesize zeolite in neutral and acidic environments without the additional mineralizing agents not only broadens the current view of traditional zeolite synthesis but also provides a new approach to control the silanol nest content of zeolite catalysts. [ABSTRACT FROM AUTHOR]

Immune checkpoint protein blockade (ICB) has emerged as a powerful immunotherapy approach, but suppressing immune‐related adverse events (irAEs) for noncancerous cells and normal tissues remains challenging. Activatable ICB has been developed with tumor microenvironment highly‐expressed molecules as stimuli, but they still lack precision and efficiency considering the diffusion of stimuli molecules in whole tumor tissue. Here we assemble PD−L1 with a duplex DNA strand, termed as "safety catch", to regulate its accessibility for ICB. The safety catch remains at "on" status for noncancerous cells to prevent ICB binding to PD−L1. Cancer cell membrane protein c‐Met acts as a trigger protein to react with safety catch, which selectively exposes its hybridization region for ICB reagent. The ICB reagent is a retractable DNA nanostring with repeating hairpin‐structural units, whose contraction drives PD−L1 clustering with endocytosis‐guided degradation. The safety catch, even remained at "safety on" status, is removed from the cell membrane via a DNA strand displacement reaction to minimize its influence on noncancerous cells. This strategy demonstrates selective and potent immunotherapeutic capabilities only against cancer cells both in vitro and in vivo, and shows effective suppression of irAEs in normal tissues, therefore would become a promising approach for precise immunotherapy in mice. [ABSTRACT FROM AUTHOR]

Rechargeable Li−Cl2 battery is a promising high energy density battery system. However, reasonable cycle life could only be achieved under low specific capacities due to the sluggish oxidation of LiCl to Cl2. Herein, we propose an amine‐functionalized covalent organic framework (COF) with catalytic activity, namely COF−NH2, that significantly decreases the oxidation barrier of LiCl and accelerates the oxidation kinetics of LiCl in Li−Cl2 cell. The resulting Li−Cl2 cell using COF−NH2 (Li−Cl2@COF−NH2) simultaneously exhibits low overpotential, ultrahigh discharge capacity up to 3500 mAh/g and a promoted utilization ratio of deposited LiCl at the first cycle (UR−LiCl) of 81.4 %, which is one of the highest reported values to date. Furthermore, the Li−Cl2@COF−NH2 cell could be stably cycled for over 200 cycles when operating at a capacity of 2000 mAh/g at −20 °C with a Coulombic efficiency (CE) of ≈100 % and a discharge plateau of 3.5 V. Our superior Li−Cl2 batteries enabled by organocatalyst enlighten an arena towards high‐energy storage applications. [ABSTRACT FROM AUTHOR]

Utilizing intermolecular hydrogen‐bonding interactions stands for an effective approach in advancing the efficiency and stability of small‐molecule acceptors (SMAs) for polymer solar cells. Herein, we synthesized three SMAs (Qo1, Qo2, and Qo3) using indeno[1,2‐b]quinoxalin‐11‐one (Qox) as the electron‐deficient group, with the incorporation of a methylation strategy. Through crystallographic analysis, it is observed that two Qox‐based methylated acceptors (Qo2 and Qo3) exhibit multiple hydrogen bond‐assisted 3D network transport structures, in contrast to the 2D transport structure observed in gem‐dichlorinated counterpart (Qo4). Notably, Qo2 exhibits multiple and stronger hydrogen‐bonding interactions compared with Qo3. Consequently, PM6 : Qo2 device realizes the highest power conversion efficiency (PCE) of 18.4 %, surpassing the efficiencies of devices based on Qo1 (15.8 %), Qo3 (16.7 %), and Qo4 (2.4 %). This remarkable PCE in PM6 : Qo2 device can be primarily ascribed to the enhanced donor‐acceptor miscibility, more favorable medium structure, and more efficient charge transfer and collection behavior. Moreover, the PM6 : Qo2 device demonstrates exceptional thermal stability, retaining 82.8 % of its initial PCE after undergoing annealing at 65 °C for 250 hours. Our research showcases that precise methylation, particularly targeting the formation of intermolecular hydrogen‐bonding interactions to tune crystal packing patterns, represents a promising strategy in the molecular design of efficient and stable SMAs. [ABSTRACT FROM AUTHOR]

Owing to outstanding performances, nickel‐based electrocatalysts are commonly used in electrochemical alcohol oxidation reactions (AORs), and the active phase is usually vacancy‐rich nickel oxide/hydroxide (NiOxHy) species. However, researchers are not aware of the catalytic role of atom vacancy in AORs. Here, we study vacancy‐induced catalytic mechanisms for AORs on NiOxHy species. As to AORs on oxygen‐vacancy‐poor β‐Ni(OH)2, the only redox mediator is electrooxidation‐induced electrophilic lattice oxygen species, which can only catalyze the dehydrogenation process (e.g. the electrooxidation of primary alcohol to carboxylic acid) instead of the C−C bond cleavage. Hence, vicinal diol electrooxidation reaction involving the C−C bond cleavage is not feasible with oxygen‐vacancy‐poor β‐Ni(OH)2. Only through oxygen vacancy‐induced adsorbed oxygen‐mediated mechanism, can oxygen‐vacancy‐rich NiOxHy species catalyze the electrooxidation of vicinal diol to carboxylic acid and formic acid accompanied with the C−C bond cleavage. Crucially, we examine how vacancies and vacancy‐induced catalytic mechanisms work during AORs on NiOxHy species. [ABSTRACT FROM AUTHOR]

Adoptive T lymphocyte (T cell) transfer and tumour‐specific peptide vaccines are innovative cancer therapies. An accurate assessment of the specific reactivity of T cell receptors (TCRs) to tumour antigens is required because of the high heterogeneity of tumour cells and the immunosuppressive tumour microenvironment. In this study, we report a label‐free electrochemiluminescence (ECL) imaging approach for recognising and discriminating between TCRs and tumour‐specific antigens by imaging the immune synapses of T cells. Various T cell stimuli, including agonistic antibodies, auxiliary molecules, and tumour‐specific antigens, were modified on the electrode's surface to allow for their interaction with T cells bearing different TCRs. The formation of immune synapses activated by specific stimuli produced a negative (shadow) ECL image, from which T cell antigen recognition and discrimination were evaluated by analysing the spreading area and the recognition intensity of T cells. This approach provides an easy way to assess TCR‐antigen specificity and screen both of them for immunotherapies. [ABSTRACT FROM AUTHOR]

Tumor‐associated macrophages (TAMs) play a critical role in the immunosuppressive solid tumor microenvironment (TME), yet in situ engineering of TAMs for enhanced tumor immunotherapy remains a significant challenge in translational immuno‐oncology. Here, we report an innovative nanodrug‐delivering‐drug (STNSP@ELE) strategy that leverages two‐dimensional (2D) stanene‐based nanosheets (STNSP) and β‐Elemene (ELE), a small‐molecule anticancer drug, to overcome TAM‐mediated immunosuppression and improve chemo‐immunotherapy. Our results demonstrate that both STNSP and ELE are capable of polarizing the tumor‐supportive M2‐like TAMs into a tumor‐suppressive M1‐like phenotype, which acts with the ELE chemotherapeutic to boost antitumor responses. In vivo mouse studies demonstrate that STNSP@ELE treatment can reprogram the immunosuppressive TME by significantly increasing the intratumoral ratio of M1/M2‐like TAMs, enhancing the population of CD4+ and CD8+ T lymphocytes and mature dendritic cells, and elevating the expression of immunostimulatory cytokines in B16F10 melanomas, thereby promoting a robust antitumor response. Our study not only demonstrates that the STNSP@ELE chemo‐immunotherapeutic nanoplatform has immune‐modulatory capabilities that can overcome TAM‐mediated immunosuppression in solid tumors, but also highlights the promise of this nanodrug‐delivering‐drug strategy in developing other nano‐immunotherapeutics and treating various types of immunosuppressive tumors. [ABSTRACT FROM AUTHOR]

Metallic zinc (Zn) is considered as one of the most attractive anode materials for the post‐lithium metal battery systems owing to the high theoretical capacity, low cost, and intrinsic safety. However, the Zn dendrites and parasitic side reaction impede its application. Herein, we propose a new principle of regulating p‐band center of metal oxide protective coating to balance Zn adsorption energy and migration energy barrier for effective Zn deposition and stripping. Experimental results and theoretical calculations indicate that benefiting from the uniform zincophilic nucleation sites and fast Zn transport on indium tin oxide (ITO), highly stable and reversible Zn anode can be achieved. As a result, the I−Zn symmetrical cell achieves highly reversible Zn deposition/stripping with an extremely low overpotential of 9 mV and a superior lifespan over 4000 h. The Cu/I−Zn asymmetrical cell exhibits a long lifetime of over 4000 cycles with high average coulombic efficiency of 99.9 %. Furthermore, the assembled I−Zn/AC full cell exhibits an excellent lifetime for 70000 cycles with nearly 100 % capacity retention. This work provides a general strategy and new insight for the construction of efficient Zn anode protection layer. [ABSTRACT FROM AUTHOR]

Catalytic ozone (O3) decomposition at high relative humidity (RH) remains a great challenge due to the catalysts poison and deactivation under high humidity. Here, we firstly elaborate the role of water activation and the corresponding mechanism of the promoted O3 decomposition over the three‐dimensional monolithic molybdenum oxide/graphdiyne (MoO3/GDY) catalyst. The O3 decomposition over MoO3/GDY reaches up to 100 % under high humid condition (75 % RH) at room temperature, which is 4.0 times as high as that of dry conditions, significantly surpasses other carbon‐based MoO3 materials(≤7.1 %). The sp‐hybridized carbon in GDY donates electrons to MoO3 along the C−O−Mo bond, facilitating water activation to form hydroxyl species. As a result, hydroxyl species dissociated from water act as new active sites, promoting the adsorption of O3 and the generation of new intermediate species (hydroxyl ⋅OH and superoxo ⋅O2−), which significantly lowers the energy barriers of O3 decomposition (0.57 eV lower than dry conditions). [ABSTRACT FROM AUTHOR]

The electrochemical conversion of nitrate pollutants into value‐added ammonia is a feasible way to achieve artificial nitrogen cycle. However, the development of electrocatalytic nitrate‐to‐ammonia reduction reaction (NO3−RR) has been hampered by high overpotential and low Faradaic efficiency. Here we develop an iron single‐atom catalyst coordinated with nitrogen and phosphorus on hollow carbon polyhedron (denoted as Fe−N/P−C) as a NO3−RR electrocatalyst. Owing to the tuning effect of phosphorus atoms on breaking local charge symmetry of the single‐Fe‐atom catalyst, it facilitates the adsorption of nitrate ions and enrichment of some key reaction intermediates during the NO3−RR process. The Fe−N/P−C catalyst exhibits 90.3 % ammonia Faradaic efficiency with a yield rate of 17980 μg h−1 mgcat−1, greatly outperforming the reported Fe‐based catalysts. Furthermore, operando SR‐FTIR spectroscopy measurements reveal the reaction pathway based on key intermediates observed under different applied potentials and reaction durations. Density functional theory calculations demonstrate that the optimized free energy of NO3−RR intermediates is ascribed to the asymmetric atomic interface configuration, which achieves the optimal electron density distribution. This work demonstrates the critical role of atomic‐level precision modulation by heteroatom doping for the NO3−RR, providing an effective strategy for improving the catalytic performance of single atom catalysts in different electrochemical reactions. [ABSTRACT FROM AUTHOR]

Water electrolysis for H2 production is restricted by the sluggish oxygen evolution reaction (OER). Using the thermodynamically more favorable hydrazine oxidation reaction (HzOR) to replace OER has attracted ever‐growing attention. Herein, we report a twisted NiCoP nanowire array immobilized with Ru single atoms (Ru1−NiCoP) as superior bifunctional electrocatalyst toward both HzOR and hydrogen evolution reaction (HER), realizing an ultralow working potential of −60 mV and overpotential of 32 mV for a current density of 10 mA cm−2, respectively. Inspiringly, two‐electrode electrolyzer based on overall hydrazine splitting (OHzS) demonstrates outstanding activity with a record‐high current density of 522 mA cm−2 at cell voltage of 0.3 V. DFT calculations elucidate the cooperative Ni(Co)−Ru−P sites in Ru1−NiCoP optimize H* adsorption, and enhance adsorption of *N2H2 to significantly lower the energy barrier for hydrazine dehydrogenation. Moreover, a self‐powered H2 production system utilizing OHzS device driven by direct hydrazine fuel cell (DHzFC) achieve a satisfactory rate of 24.0 mol h−1 m−2. [ABSTRACT FROM AUTHOR]

Electrocatalytic urea synthesis via coupling N2 and CO2 provides an effective route to mitigate energy crisis and close carbon footprint. However, the difficulty on breaking N≡N is the main reason that caused low efficiencies for both electrocatalytic NH3 and urea synthesis, which is the bottleneck restricting their industrial applications. Herein, a new mechanism to overcome the inert of the nitrogen molecule was proposed by elongating N≡N instead of breaking N≡N to realize one‐step C−N coupling in the process for urea production. We constructed a Zn−Mn diatomic catalyst with axial chloride coordination, Zn−Mn sites display high tolerance to CO poisoning and the Faradaic efficiency can even be increased to 63.5 %, which is the highest value that has ever been reported. More importantly, negligible N≡N bond breakage effectively avoids the generation of ammonia as intermediates, therefore, the N‐selectivity in the co‐electrocatalytic system reaches100 % for urea synthesis. The previous cognition that electrocatalysts for urea synthesis must possess ammonia synthesis activity has been broken. Isotope‐labelled measurements and Operando synchrotron‐radiation Fourier transform infrared spectroscopy validate that activation of N−N triple bond and nitrogen fixation activity arise from the one‐step C−N coupling process of CO species with adsorbed N2 molecules. [ABSTRACT FROM AUTHOR]

Synthesis of cyclohexanone oxime via the cyclohexanone‐hydroxylamine process is widespread in the caprolactam industry, which is an upstream industry for nylon‐6 production. However, there are two shortcomings in this process, harsh reaction conditions and the potential danger posed by explosive hydroxylamine. In this study, we presented a direct electrosynthesis of cyclohexanone oxime using nitrogen oxides and cyclohexanone, which eliminated the usage of hydroxylamine and demonstrated a green production of caprolactam. With the Fe electrocatalysts, a production rate of 55.9 g h−1 gcat−1 can be achieved in a flow cell with almost 100 % yield of cyclohexanone oxime. The high efficiency was attributed to their ability of accumulating adsorbed hydroxylamine and cyclohexanone. This study provides a theoretical basis for electrocatalyst design for C−N coupling reactions and illuminates the tantalizing possibility to upgrade the caprolactam industry towards safety and sustainability. [ABSTRACT FROM AUTHOR]

Bismuth‐based materials have been recognized as promising catalysts for the electrocatalytic CO2 reduction reaction (ECO2RR). However, they show poor selectivity due to competing hydrogen evolution reaction (HER). In this study, we have developed an edge defect modulation strategy for Bi by coordinating the edge defects of bismuth (Bi) with sulfur, to promote ECO2RR selectivity and inhibit the competing HER. The prepared catalysts demonstrate excellent product selectivity, with a high HCOO− Faraday efficiency of ≈95 % and an HCOO− partial current of ≈250 mA cm−2 under alkaline electrolytes. Density function theory calculations reveal that sulfur tends to bind to the Bi edge defects, reducing the coordination‐unsaturated Bi sites (*H adsorption sites), and regulating the charge states of neighboring Bi sites to improve *OCHO adsorption. This work deepens our understanding of ECO2RR mechanism on bismuth‐based catalysts, guiding for the design of advanced ECO2RR catalysts. [ABSTRACT FROM AUTHOR]

The electrocatalytic C−N coupling from carbon dioxide and nitrate under ambient conditions is kind of sustainable and promising alternative method for urea synthesis. To date, the influence of catalyst surface properties on molecular adsorption configuration and electrocatalytic urea synthesis activity is unclear. In this work, we proposed that the urea synthesis activity is closely linked with the localized surface charge on bimetallic electrocatalysts, it is found that a negatively charged surface induces C‐bound path and boosts urea synthesis. The urea yield rate can reach 13.1 mmol g−1 h−1 on negatively charged Cu97In3‐C, which is about 13 times that of positively charged Cu30In70‐C counterpart with O‐bound surface. This conclusion also applies to Cu−Bi and Cu−Sn systems. The molecular modification shifts the surface of Cu97In3‐C to positively charged state, which leads to a sharp decline in urea synthesis performance. We demonstrated that the C‐bound surface is more favorable than O‐bound one to boost electrocatalytic urea synthesis. [ABSTRACT FROM AUTHOR]

Using sunlight to produce valuable chemicals and fuels from carbon dioxide (CO2), i.e. artificial photosynthesis (AP) is a promising strategy to achieve solar energy storage and a negative carbon cycle. However, selective synthesis of C2 compounds with a high CO2 conversion rate remains challenging for current AP technologies. We performed CO2 photoelectroreduction over a graphene/silicon carbide (SiC) catalyst under simulated solar irradiation with ethanol (C2H5OH) selectivity of>99 % and a CO2 conversion rate of up to 17.1 mmol gcat−1 h−1 with sustained performance. Experimental and theoretical investigations indicated an optimal interfacial layer to facilitate the transfer of photogenerated electrons from the SiC substrate to the few‐layer graphene overlayer, which also favored an efficient CO2 to C2H5OH conversion pathway. [ABSTRACT FROM AUTHOR]

Microbial cell factories provide a green and sustainable opportunity to produce value‐added products from renewable feedstock. However, the leakage of toxic or volatile intermediates decreases the efficiency of microbial cell factories. In this study, membraneless organelles (MLOs) were reconstructed in Saccharomyces cerevisiae by the disordered protein sequence A‐IDPs. A regulation system was designed to spatiotemporally regulate the size and rigidity of MLOs. Manipulating the MLO size of strain ZP03‐FM, the amounts of assimilated methanol and malate were increased by 162 % and 61 %, respectively. Furthermore, manipulating the MLO rigidity in strain ZP04‐RB made acetyl‐coA synthesis from oxidative glycolysis change to non‐oxidative glycolysis; consequently, CO2 release decreased by 35 % and the n‐butanol yield increased by 20 %. This artificial MLO provides a strategy for the co‐localization of enzymes to channel C1 starting materials into value‐added chemicals. [ABSTRACT FROM AUTHOR]

Messenger RNA (mRNA) is the fundamental information transfer system in the cell. Tracking single mRNA from transcription to degradation with fluorescent probes provides spatiotemporal information in cells about how the genetic information is transferred from DNA to proteins. The traditional single mRNA imaging approach utilizes RNA hairpins (e.g. MS2) and tethered fluorescent protein as probes. As an exciting alternative, RNA aptamers: small‐molecule fluorophores (SFs) systems have emerged as novel single mRNA imaging probes since 2019, exhibiting several advantages including fluorogenic ability and minimal perturbation. This review summarizes all five reported RNA aptamers: SFs systems for single mRNA imaging in living cells so far. It also discusses the challenges and provides prospects for single mRNA imaging applications. This review is expected to inspire researchers to develop RNA aptamers: SFs systems for studying gene expression at single‐molecule resolution in cells. [ABSTRACT FROM AUTHOR]

Nanomotors are appealing drug carriers, and the strength of the propelling force is important for their motion capability. Though high motion efficiency has been achieved with 808 nm light driven Janus‐structured noble metal nanomotors, the NIR‐I light penetration depth and material biocompatibility limit their broad application. Herein, we develop a 1064 nm NIR‐II light driven asymmetric hydrogel nanomotor (AHNM) with high motion capability and load it with doxorubicin for enhanced immunochemotherapy. Magnetic field assisted photopolymerization generates an asymmetric distribution of Fe3O4@Cu9S8 nanoparticles in the AHNM, producing self‐thermophoresis as driving force under NIR‐II irradiation. The AHNM is also functionalized with dopamine for the capture and retention of tumor‐associated antigens to boost immune activation. The as‐obtained NIR‐II light driven AHNM has a high tumor tissue penetration capability and enhances immunochemotherapy, providing a promising strategy for cancer therapy. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZBs) show promises for large‐scale energy storage. However, the zinc utilization rate (ZUR) is generally low due to side reactions in the aqueous electrolyte caused by the active water molecules. Here, we design a novel solvation structure in the electrolyte by introduction of sulfolane (SL). Theoretical calculations, molecular dynamics simulations and experimental tests show that SL remodels the primary solvation shell of Zn2+, which significantly reduces the side reactions of Zn anode and achieves high ZUR under large capacities. Specifically, the symmetric and asymmetric cells could achieve a maximum of ∼96 % ZUR at an areal capacity of 24 mAh cm−2. In a ZUR of ∼67 %, the developed Zn−V2O5 full cell can be stably cycled for 500 cycles with an energy density of 180 Wh kg−1 and Zn‐AC capacitor is stable for 5000 cycles. This electrolyte structural engineering strategy provides new insight into achieving high ZUR of Zn anodes for high performance AZBs. [ABSTRACT FROM AUTHOR]

Strong metal‐support interactions characteristic of the encapsulation of metal particles by oxide overlayers have been widely observed on large metal nanoparticles, but scarcely occur on small nanoclusters (<2 nm) for which the metal‐support interactions remain elusive. Herein, we study the structural evolution of Pt nanoclusters (1.5 nm) supported on anatase TiO2 upon high‐temperature H2 reduction. The Pt nanoclusters start to partially evolve into a CsCl‐type PtTi intermetallic compound when the reduction temperature reaches 400 °C. Upon 700 °C reduction, the PtTi nanoparticles are exclusively formed and grow epitaxially along the TiO2 (101) crystal faces. The thermodynamics of the formation of PtTi via migration of reduced Ti atoms into Pt cluster is unraveled by theoretical calculations. The thermally stable PtTi intermetallic compound, with single‐atom Pt isolated by Ti, exhibits enhanced catalytic activity and promoted catalytic durability for CO oxidation. [ABSTRACT FROM AUTHOR]

The in‐depth mechanism on the simultaneous activation of O2 and surface lattice O2− on one active metallic site has not been elucidated yet. Herein, we report a strategy for the construction of abundant oxygen activation sites by rational design of Cu1/TiO2 single atom catalysts (SACs). The charge transfer between isolated Cu and TiO2 support generates abundant CuI and 2‐coordinated Olat sites in Cu1−O−Ti hybridization structure, which facilitates the chemisorption and activation of O2 molecules. Simultaneously, the Cu1−O−Ti induced TiO2 lattice distortion activate the adjacent surface lattice O2−, achieving the dual activation of O2 and surface lattice O2−. The Cu1−O−Ti active site switches the CO oxidation mechanism from Eley‐Rideal (80 °C) to Mars–van Krevelen route (200 °C) with the increase of reaction temperature. The dual activation of O2 and surface lattice O2− can by modulating the electron properties of SACs can boost the heterogeneous catalytic oxidation activity. [ABSTRACT FROM AUTHOR]

Single atom catalysts (SACs) have been widely studied in the field of CO2 electroreduction, but industrial‐level current density and near‐unity product selectivity are still difficult to achieve. Herein, a diatomic site catalysts (DASCs) consisting of Co‐Cu hetero‐diatomic pairs is synthesized. The CoCu DASC exhibits excellent selectivity with the maximum CO Faradaic efficiency of 99.1 %. The CO selectivity can maintain above 95 % over a wide current density range from 100 mA cm−2 to 500 mA cm−2. The maximum CO partial current density can reach to 483 mA cm−2 in flow cell, far exceed industrial‐level current density requirements (>200 mA cm−2). Theoretical calculation reveals that the synergistic catalysis of the Co‐Cu bimetallic sites reduce the activation energy and promote the formation of intermediate *COOH. This work shows that the introduction of another metal atom into SACs can significantly affect the electronic structure and then enhance the catalytic activity of SACs. [ABSTRACT FROM AUTHOR]

Selective electrocatalytic oxidation of alcohols to value‐added aldehydes has attracted increasing attention. However, due to its higher reactivity than alcohol, the aldehyde is easily over‐oxidized to acid in alkaline electrolytes. Herein we realize the selective electrooxidation of alcohol to aldehyde on NiO by tuning the local microenvironment to salt out the aldehyde from the reaction system. The origin of the high selectivity was found to be the inhibition of the hydration of aldehydes, which is the result of the decreased alkalinity and the increased cation and substrate concentration. This strategy could salt out the aldehyde at the gas|electrolyte interface from the electrooxidation of alcohol with 100 % selectivity and be easily extended to other selective oxidation reactions, such as 5‐hydroxymethyl furfural (HMF) to 2,5‐furandicarboxaldehyde (DFF) and amine to an imine. [ABSTRACT FROM AUTHOR]

Electrochemical conversion of CO2 into valuable feedstocks is a promising strategy for carbon neutrality. However, it remains a challenge to possess a large current density, a high faradaic efficiency and excellent stability for practical applications of CO2 utilization. Herein, we report a facile tactic that enables exceedingly efficient CO2 electroreduction to CO by virtue of low‐coordination chloride ion (Cl−) adsorption on a silver hollow fiber (Ag HF) electrode. A CO faradaic efficiency of 92.3 % at a current density of one ampere per square centimeter (1 A cm−2) in 3.0 M KCl with a sustained performance observed during a 150‐hour test was achieved, which is better than state‐of‐the‐art electrocatalysts. The electrochemical results and density functional theory (DFT) calculations suggested a low‐coordination Cl− adsorption on surface of Ag HF, which not only suppressed the competitive hydrogen evolution reaction (HER), but also facilitated the CO2 reduction kinetics. [ABSTRACT FROM AUTHOR]

Zeolites have found tremendous applications in the chemical industry. However, the dynamic nature of their active sites under the flow of adsorbate molecules for adsorption and catalysis is unclear, especially in operando conditions, which could be different from the as‐synthesized structures. In the present study, we report a structural transformation of the adsorptive active sites in SAPO‐34 zeolite by using acetone as a probe molecule under various temperatures. The combination of solid‐state nuclear magnetic resonance, in situ variable‐temperature synchrotron X‐ray diffraction, and in situ diffuse‐reflectance infrared Fourier‐transform spectroscopy allow a clear identification and quantification that the chemisorption of acetone can convert the classical Brønsted acid site adsorption mode to an induced Frustrated Lewis Pairs adsorption mode at increasing temperatures. Such facile conversion is also supported by the calculations of ab‐initio molecular‐dynamics simulations. This work sheds new light on the importance of the dynamic structural alteration of active sites in zeolites with adsorbates at elevated temperatures. [ABSTRACT FROM AUTHOR]

The frustrated Lewis pair (FLP) concept in homogeneous catalysis was extended to heterogeneous catalysis via the supramolecular system of FLP between deprotonated zeolite framework oxygens and confined carbocations in methanol‐to‐olefin (MTO) reactions. In this FLP, the polymethylbenzenium (PMB+) functioned as the Lewis acid to accept an electron pair, and the deprotonated framework oxygen site acted as the Lewis base to donate an electron pair. This FLP theoretically demonstrated the ability to undergo H2 heterolysis and alkanes dehydrogenation, and this was further confirmed by gas chromatography–mass spectrometer (GC‐MS) catalytic experiments inside FLP‐containing chabazite zeolites. All these findings not only bring new recognition to the carbocation chemistry in zeolite cages but also put forward a new reaction pathway as one part of MTO reactions. [ABSTRACT FROM AUTHOR]

An amine‐functionalized covalent organic framework with catalytic activity is demonstrated to significantly decrease the oxidation barrier and accelerate the oxidation kinetics of LiCl in a rechargeable Li‐Cl2 battery. The developed battery exhibits low overpotential and ultrahigh discharge capacity with good stability in a wide temperature range, as reported by Wei Chen, Shenxiang Zhang et al. in their Research Article (e202315931)...By Yan Xu; Mingming Wang; Muhammad Sajid; Yahan Meng; Zehui Xie; Lidong Sun; Jian Jin; Wei Chen and Shenxiang ZhangReported by Author; Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

NO is a harmful pollutant to the environment. The traditional removal of NO is hindered by the harsh operating conditions and sacrifice of value‐added chemicals. Efficient electrocatalytic oxidation of NO was achieved over plasma‐treated commercial carbon cloth, serving as a promising anode substitution reaction to couple with the hydrogen evolution reaction without consumption of hydrogen‐containing resources. The introduction of carboxyl groups onto the carbon cloth boosted the electrocatalytic activity via the enhancement of NO chemisorption. Only potentials of 1.39 V and 1.07 V were applied to reach the current density of 10 mA cm−2 in neutral and acidic conditions, respectively, which is superior to the state‐of‐the‐art electrocatalysts for oxygen evolution. Energy and environmental concerns on fossil‐fuel‐derived hydrogen production, ammonia manufacture and nitrate synthesis, are greatly alleviated. This work provides an original strategy to realize the resource utilization of NO, the sustainable nitrate synthesis and hydrogen production in a green and economical way. [ABSTRACT FROM AUTHOR]

Shape complementarity is a biological craft for precisely binding substrates at protein–protein interfaces. An analogy to such a function can be drawn conceptually for crystalline porous solids; yet the manifested entities are rare in reticular chemistry. The bottleneck‐shaped pores carved out of a metal‐organic framework, Zn(MIBA)2 (aka. MAF‐stu‐13), can perfectly accommodate benzene molecules. Remarkably, its framework adapts to the optimal guest binding‐the enhanced host–guest interactions in the neck in turn minimize the guest‐guest repulsion in the pore to the extent it turns into attraction‐as demonstrated by the combined X‐ray structural and DFT computational studies. This adaptive material can be used for liquid‐phase production of ultrahigh‐purity (≥99 %) cyclohexane, achieving a balance between uptake capacity and separation selectivity and surpassing the performances of other porous and nonporous crystals reported recently (e.g. product purity 99.4 % vs. 97.5 % to date). [ABSTRACT FROM AUTHOR]

Nickel hydroxide (Ni(OH)2) is a promising electrocatalyst for the 5‐hydroxymethylfurfural oxidation reaction (HMFOR) and the dehydronated intermediates Ni(OH)O species are proved to be active sites for HMFOR. In this study, Ni(OH)2 is modified by platinum to adjust the electronic structure and the current density of HMFOR improves 8.2 times at the Pt/Ni(OH)2 electrode compared with that on Ni(OH)2 electrode. Operando methods reveal that the introduction of Pt optimized the redox property of Ni(OH)2 and accelerate the formation of Ni(OH)O during the catalytic process. Theoretical studies demonstrate that the enhanced Ni(OH)O formation kinetics originates from the reduced dehydrogenation energy of Ni(OH)2. The product analysis and transition state simulation prove that the Pt also reduces adsorption energy of HMF with optimized adsorption behavior as Pt can act as the adsorption site of HMF. Overall, this work here provides a strategy to design an efficient and universal nickel‐based catalyst for HMF electro‐oxidation, which can also be extended to other Ni‐based catalysts such as Ni(HCO3)2 and NiO. [ABSTRACT FROM AUTHOR]

Developing self‐oscillating soft actuators that enable autonomous, continuous, and directional locomotion is significant in biomimetic soft robotics fields, but remains great challenging. Here, an untethered soft photoactuators based on covalently‐bridged black phosphorus‐carbon nanotubes heterostructure with self‐oscillation and phototactic locomotion under constant light irradiation is designed. Owing to the good photothermal effect of black phosphorus heterostructure and thermal deformation of the actuator components, the new actuator assembled by heterostructured black phosphorus, polymer and paper produces light‐driven reversible deformation with fast and large response. By using this actuator as mechanical power and designing a robot configuration with self‐feedback loop to generate self‐oscillation, an inchworm‐like actuator that can crawl autonomously towards the light source is constructed. Moreover, due to the anisotropy and tailorability of the actuator, an artificial crab robot that can simulate the sideways locomotion of crabs and simultaneously change color under light irradiation is also realized. [ABSTRACT FROM AUTHOR]

Nanogels have been identified as outstanding nanocarrier candidates for drug delivery due to their desirable physiochemical properties and versatile applicability for diverse therapeutic molecules and imaging probes. One of the main challenges that hinder the clinical translation of nanogels is the low efficiency of drug delivery to the target sites because of the complex biological barriers during the in vivo journey. The purpose of this review is to examine and summarize the recent advances on the rational design and structural modulation of nanogels to overcome the barriers and challenges on the way to the site of action following various dosing modes. In particular, the functional moieties or domains have been incorporated in the nanogels, allowing them to spontaneously regulate their structure and physiochemical properties to cross one or more of the multifaceted barriers. In addition, the future perspectives are presented with regards to opportunities and challenges for the precise and efficient therapeutic use of nanogel formulations. [ABSTRACT FROM AUTHOR]

Ultrasound (US)‐mediated sonodynamic therapy (SDT) has emerged as a superior modality for cancer treatment owing to the non‐invasiveness and high tissue‐penetrating depth. However, developing biocompatible nanomaterial‐based sonosensitizers with efficient SDT capability remains challenging. Here, we employed a liquid‐phase exfoliation strategy to obtain a new type of two‐dimensional (2D) stanene‐based nanosheets (SnNSs) with a band gap of 2.3 eV, which is narrower than those of the most extensively studied nano‐sonosensitizers, allowing a more efficient US‐triggered separation of electron (e−)‐hole (h+) pairs for reactive oxygen species (ROS) generation. In addition, we discovered that such SnNSs could also serve as robust near‐infrared (NIR)‐mediated photothermal therapy (PTT) agents owing to their efficient photothermal conversion, and serve as nanocarriers for anticancer drug delivery owing to the inherent 2D layered structure. This study not only presents general nanoplatforms for SDT‐enhanced combination cancer therapy, but also highlights the utility of 2D SnNSs to the field of nanomedicine. [ABSTRACT FROM AUTHOR]

The nitrogenous nucleophile electrooxidation reaction (NOR) plays a vital role in the degradation and transformation of available nitrogen. Focusing on the NOR mediated by the β‐Ni(OH)2 electrode, we decipher the transformation mechanism of the nitrogenous nucleophile. For the two‐step NOR, proton‐coupled electron transfer (PCET) is the bridge between electrocatalytic dehydrogenation from β‐Ni(OH)2 to β‐Ni(OH)O, and the spontaneous nucleophile dehydrogenative oxidation reaction. This theory can give a good explanation for hydrazine and primary amine oxidation reactions, but is insufficient for the urea oxidation reaction (UOR). Through operando tracing of bond rupture and formation processes during the UOR, as well as theoretical calculations, we propose a possible UOR mechanism whereby intramolecular coupling of the N−N bond, accompanied by PCET, hydration and rearrangement processes, results in high performance and ca. 100 % N2 selectivity. These discoveries clarify the evolution of nitrogenous molecules during the NOR, and they elucidate fundamental aspects of electrocatalysis involving nitrogen‐containing species. [ABSTRACT FROM AUTHOR]

Carbonium ions are an important class of reaction intermediates, but their dynamic evolution is difficult to be monitored by in situ techniques under experimental conditions because of their extremely short lifetime. Probably the most famous case is 2‐norbornyl cation (2NB+): its existing form (classical or non‐classical) had been debated for decades, until the concrete proof of non‐classical geometry was achieved by X‐ray crystallographic characterization at ultra‐low temperature (40 K) and super acidic environment. However, we lack the understanding about 2NB+ at ambient conditions. Herein, by taking advantage of the confinement effect and delocalized acidic environment of zeolites, we successfully stabilized 2NB+ and unequivocally confirmed its "non‐classical" structure inside the ZSM‐5 zeolite by ab initio molecular dynamics simulations and 13C solid‐state nuclear magnetic resonance experiments. It is the first time to in situ observe the non‐classical 2NB+ without the super acidic environment at ambient temperature, which provides a new strategy to expand the carbocation chemistry. [ABSTRACT FROM AUTHOR]

Infrared spectra for a series of asymmetric proton‐bound dimers with protonated trimethylamine (TMA‐H+) as the proton donor were recorded and analyzed. The frequency of the N–H+ stretching mode is expected to red shift as the proton affinity of proton acceptors increases. The observed band, however, shows a peculiar splitting of approximately 300 cm−1 with the intensity shifting pattern resembling a two‐level system. Theoretical investigation reveals that the observed band splitting and its extraordinarily large gap of around 300 cm−1 is a result of strong coupling between the fundamental of the proton stretching mode and overtone states of the two proton bending modes, that is commonly known as Fermi resonance (FR). We also provide a general theoretical model to link the strong FR coupling to the quasi‐two‐level system. Since the model does not depend on the molecular specification of TMA‐H+, the strong coupling we observed is an intrinsic property associated with proton motions. [ABSTRACT FROM AUTHOR]

A metal‐free C−H allylation strategy is described to access diverse functionalized ortho‐allyl‐iodoarenes. The method employs hypervalent (diacetoxy)iodoarenes and proceeds through the iodane‐guided "iodonio‐Claisen" allyl transfer. The use of allylsilanes bearing electron‐withdrawing functional groups unlocks the functionalization of a broad range of substrates, including electron‐neutral and electron‐poor rings. The resulting ortho‐allylated iodoarenes are versatile building blocks, with examples of downstream transformation including a concise synthesis of the experimental antimitotic core of Dosabulin. DFT calculations shed additional light on the reaction mechanism, with notable aspects including the aromatic character of the transition‐state structure for the [3,3] sigmatropic rearrangement, as well as the highly stereoconvergent nature of the trans‐product formation. [ABSTRACT FROM AUTHOR]

Herein, we introduce the cyclic 8π‐electron (C8π) molecule N,N′‐diaryl‐dihydrodibenzo[a,c]phenazine (DPAC) as a dual‐functional donor to establish a series of new donor–linker–acceptor (D–L–A) dyads DLA1–DLA5. The excited‐state bent‐to‐planar dynamics of DPAC regulate the energy gap of the donor, while the acceptors A1–A5 are endowed with different energy gaps and HOMO/LUMO levels. As a result, the rate and efficiency of the excited‐state electron transfer vs. energy transfer can be finely harnessed, which is verified via steady‐state spectroscopy and time‐resolved emission measurements. This comprehensive approach demonstrates, for the first time, the manifold of excited‐state properties governed by bifunctional donor‐based D–L–A dyads, including bent‐to‐planar, photoinduced electron transfer (PET) from excited donor to acceptor (oxidative‐PET), fluorescence resonance energy transfer (FRET), bent‐to‐planar followed by electron transfer (PFET), and PET from donor to excited acceptor (reductive‐PET). [ABSTRACT FROM AUTHOR]

Hypervalent organoiodane reagents are ubiquitous in organic synthesis, both as oxidants and as electrophilic group‐transfer agents. In addition to these hallmark applications, a complementary strategy is gaining momentum that exploits the ability of λ3‐iodanes to undergo iodine‐to‐arene group transfer, for example, via iodonio‐Claisen‐type rearrangement processes. This Minireview discusses recent advances in the use of this method to access a variety of the C−H‐functionalized iodoarenes. While Section 2 is focused on the ortho C−H propargylation, allylation, and the more unusual para C−H benzylation, Section 3 is devoted to the C‐arylation of enol and phenol substrates. The accompanying discussion includes mechanistic considerations and goes into the synthetic applications of the final iodoarene cores. The Minireview concludes with further conceptual extensions of the method, including the use of non‐conventional coupling partners (for example, cyanoalkylation), improved access to λ3‐iodane building blocks, and the development of iterative approaches to polysubstituted iodoarenes. [ABSTRACT FROM AUTHOR]

There are a large number of zeolites, such as ITH, that cannot be prepared in the aluminosilicate form. Now, the successful synthesis of aluminosilicate ITH zeolite using a simple cationic oligomer as an organic template is presented. Key to the success is that the cationic oligomer has a strong complexation ability with aluminum species combined with a structural directing ability for the ITH structure similar to that of the conventional organic template. The aluminosilicate ITH zeolite has very high crystallinity, nanosheet‐like crystal morphology, large surface area, fully four‐coordinated Al species, and abundant acidic sites. Methanol‐to‐propylene (MTP) tests reveal that the Al‐ITH zeolite shows much higher selectivity for propylene and longer lifetime than commercial ZSM‐5. FCC tests show that Al‐ITH zeolite is a good candidate as a shape‐selective FCC additive for enhancing propylene and butylene selectivity. [ABSTRACT FROM AUTHOR]

Multiple bonds between boron and transition metals are known in many borylene (:BR) complexes via metal dπ→BR back‐donation, despite the electron deficiency of boron. An electron‐precise metal–boron triple bond was first observed in BiB2O− [Bi≡B−B≡O]− in which both boron atoms can be viewed as sp‐hybridized and the [B−BO]− fragment is isoelectronic to a carbyne (CR). To search for the first electron‐precise transition‐metal‐boron triple‐bond species, we have produced IrB2O− and ReB2O− and investigated them by photoelectron spectroscopy and quantum‐chemical calculations. The results allow to elucidate the structures and bonding in the two clusters. We find IrB2O− has a closed‐shell bent structure (Cs, 1A′) with BO− coordinated to an Ir≡B unit, (−OB)Ir≡B, whereas ReB2O− is linear (C∞v, 3Σ−) with an electron‐precise Re≡B triple bond, [Re≡B−B≡O]−. The results suggest the intriguing possibility of synthesizing compounds with electron‐precise M≡B triple bonds analogous to classical carbyne systems. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are highly regarded as the next‐generation energy‐storage devices because of their ultrahigh theoretical energy density of 2600 Wh kg−1. Sulfurized polyacrylonitrile (SPAN) is considered a promising sulfur cathode to substitute carbon/sulfur (C/S) composites to afford higher Coulombic efficiency, improved cycling stability, and potential high‐energy‐density Li–SPAN batteries. However, the instability of the Li‐metal anode threatens the performances of Li–SPAN batteries bringing limited lifespan and safety hazards. Li‐metal can react with most kinds of electrolyte to generate a protective solid electrolyte interphase (SEI), electrolyte regulation is a widely accepted strategy to protect Li‐metal anodes in rechargeable batteries. Herein, the basic principles and current challenges of Li–SPAN batteries are addressed. Recent advances on electrolyte regulation towards stable Li‐metal anodes in Li–SPAN batteries are summarized to suggest design strategies of solvents, lithium salts, additives, and gel electrolyte. Finally, prospects for future electrolyte design and Li anode protection in Li–SPAN batteries are discussed. [ABSTRACT FROM AUTHOR]

Ligand‐protected gold nanoclusters (AuNCs) have emerged as a new class of electrochemiluminescence (ECL) luminophores for their interesting catalytic and emission properties, although their quantum yield (ΦECL) in aqueous medium is low with a poor mechanistic understanding of the ECL process. Now it is shown that drying AuNCs on electrodes enabled both enhanced electrochemical excitation by an electrocatalytic effect, and enhanced emission by aggregation‐induced ECL (AIECL) for 6‐aza‐2‐thiothymine (ATT) protected AuNCs with triethylamine (TEA) as a coreactant. The dried ATT‐AuNCs/TEA system resulted in highly stable visual ECL with a ΦECL of 78 %, and a similar enhancement was also achieved with methionine‐capped AuNCs. The drying enabled dual‐enhancement mechanism has solved a challenging mechanistic problem for AuNC ECL probes, and can guide further rational design of ECL emitters. [ABSTRACT FROM AUTHOR]

All‐DNA scaffolds act as templates for the organization of photosystem I model systems. A series of DNA templates composed of ZnII‐protoporphyrin IX (ZnIIPPIX)‐functionalized G‐quadruplex conjugated to the 3′‐ or 5′‐end of the tyrosinamide (TA) aptamer and ZnIIPPIX/G‐quadruplex linked to the 3′‐ and 5′‐ends of the TA aptamer through a four‐thymidine bridge. Effective photoinduced electron transfer (ET) from ZnIIPPIX/G‐quadruplex to bipyridinium‐functionalized tyrosinamide, TA‐MV2+, bound to the TA aptamer units is demonstrated. The effectiveness of the primary ET quenching of ZnIIPPIX/G‐quadruplex by TA‐MV2+ controls the efficiency of the generation of TA‐MV+.. The photosystem‐controlled formation of TA‐MV+. by the different photosystems dictates the secondary activation of the ET cascade corresponding to the ferredoxin‐NADP+ reductase (FNR)‐catalysed reduction of NADP+ to NADPH by TA‐MV+. and the sequestered alcohol dehydrogenase catalysed reduction of acetophenone to 1‐phenylethanol by NADPH. [ABSTRACT FROM AUTHOR]

The construction of 2D and 3D covalent organic frameworks (COFs) from functional moieties for desired properties has gained much attention. However, the influence of COFs dimensionality on their functionalities, which can further assist in COF design, has never been explored. Now, by selecting designed precursors and topology diagrams, 2D and 3D porphyrinic COFs (2D‐PdPor‐COF and 3D‐PdPor‐COF) are synthesized. By model building and Rietveld refinement of powder X‐ray diffraction, 2D‐PdPor‐COF crystallizes as 2D sheets while 3D‐PdPor‐COF adopts a five‐fold interpenetrated pts topology. Interestingly, compared with 2D‐PdPor‐COF, 3D‐PdPor‐COF showed interesting properties, including 1) higher CO2 adsorption capacity; 2) better photocatalytic performance; and 3) size‐selective photocatalysis. Based on this study, we believe that with the incorporation of functional moieties, the dimensionality of COFs can definitely influence their functionalities. [ABSTRACT FROM AUTHOR]

The transition of peptides and proteins from the solution phase into fibrillar structures is a general phenomenon encountered in functional and aberrant biology and is increasingly exploited in soft materials science. However, the fundamental molecular events underpinning the early stages of their assembly and subsequent growth have remained challenging to elucidate. Here, we show that liquid–liquid phase separation into solute‐rich and solute‐poor phases is a fundamental step leading to the nucleation of supramolecular nanofibrils from molecular building blocks, including peptides and even amphiphilic amino acids. The solute‐rich liquid droplets act as nucleation sites, allowing the formation of thermodynamically favorable nanofibrils following Ostwald's step rule. The transition from solution to liquid droplets is entropy driven while the transition from liquid droplets to nanofibrils is mediated by enthalpic interactions and characterized by structural reorganization. These findings shed light on how the nucleation barrier toward the formation of solid phases can be lowered through a kinetic mechanism which proceeds through a metastable liquid phase. [ABSTRACT FROM AUTHOR]

Thionitrous acid (HSNO), the smallest S‐nitrosothiol, is emerging as a potential key intermediate in cellular redox regulation linking two signaling molecules H2S and NO. However, the chemical biology of HSNO remains poorly understood. A major hurdle is the lack of methods for selective detection of HSNO in biological systems. Herein, we report the rational design, synthesis, and evaluation of the first fluorescent probe TAP‐1 for HSNO detection. TAP‐1 showed high selectivity and sensitivity to HSNO in aqueous media and cells, providing a useful tool for understanding the functions of HSNO in biology. [ABSTRACT FROM AUTHOR]