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ABSTRACT Objective Methods Results Conclusion To elucidate the regional distribution of metabolic dysfunction‐associated steatohepatitis (MASH) fibrosis within the liver and to identify potential therapeutic targets for MASH fibrosis.Liver sections from healthy controls, patients with simple steatosis and MASH patients were analysed using spatial transcriptomics integrated with single‐cell RNA‐seq.Spatial transcriptomics analysis of liver tissues revealed that the fibrotic region (Cluster 9) was primarily distributed in lobules, with some fibrosis also found in the surrounding area. Integration of the single‐cell‐sequencing data set (GSE189175) showed a greater proportion of inflammatory cells (Kupffer cells and T cells) and myofibroblasts in MASH. Six genes, showing high‐ or low‐specific expression in Cluster 9, namely, ADAMTSL2, PTGDS, S100A6, PPP1R1A, ASS1 and G6PC, were identified in combination with pathology. The average expression levels of ADAMTSL2, PTGDS and S100A6 on the pathological HE staining map were positively correlated with the increase in the degree of fibrosis and aligned strongly with the distribution of fibrosis. ADAMTSL2+ myofibroblasts play a role in TNF signalling pathways and in the production of ECM structural components. Pseudotime analysis indicated that in the early stages of MASH, infiltration by T cells and Kupffer cells triggers a significant inflammatory response. Subsequently, this inflammation leads to the activation of hepatic stellate cells (HSCs), transforming them into myofibroblasts and promoting the development of liver fibrosis.This study is the first to characterise lineage‐specific changes in gene expression, subpopulation composition, and pseudotime analysis in MASH fibrosis and reveals potential therapeutic targets for this condition. [ABSTRACT FROM AUTHOR]

Silicon (Si), stands out for its abundant resources, eco‐friendliness, affordability, high capacity, and low operating potential, making it a prime candidate for high‐energy‐density lithium‐ion batteries (LIBs). Notably, the breakthrough use of nanostructured Si (nSi) has paved the way for the commercialization of Si anodes. Despite this, challenges like high processing costs, severe side reactions, and low volumetric energy density have impeded widespread industrial adoption. Micron‐scale Si (µSi) has always faced setbacks compared to nSi due to its greater volume expansion. However, recent years have witnessed a resurgence of interest in µSi‐based anodes. Capitalizing on its inherent advantages, including low cost and high tap density, µSi has once again captured the attention of both academic and industrial communities. This review begins by contrasting the strengths and weaknesses of µSi and nSi, then outline potential solutions to enhance µSi performance, covering aspects like structural regulation, composite anodes, binder design, and electrolyte exploration. Additionally, this work explores the application of machine learning‐assisted high‐throughput screening. Concluding the review, this work provides insights into the future prospects of µSi in LIBs, outlining challenges and proposing integrated coping strategies. This review anticipates that it will provide valuable perspectives for the commercial application of high‐energy‐density Si‐based anodes. [ABSTRACT FROM AUTHOR]

Anode materials based on IV main group elements like Si, Ge, and Sn show great potential for lithium‐ion batteries (LIBs) due to their high specific capacity and low working potential. However, issues such as volume expansion and lattice pulverization hinder their practical usage. To address these issues for Ge, a novel F127 triblock polymer/acetylene black dual‐assisted strategy is proposed to achieve uniform dispersion of polycrystalline Ge, enabling the preparation of Ge@C nanocomposites via hydrogen reduction. The introduced F127 triblock polymer and acetylene black serves a dual purpose to enhance electrical conductivity and prevent Ge nanoparticles from agglomeration. When tested as anode material for LIBs, the Ge@C nanocomposites exhibit exceptional electrochemical performances, demonstrating a sustained specific discharge capacity of 780 mA h g−1 at 0.2 A g−1 after 100 cycles. Moreover, the capacity remains at 767 mA h g−1 even after 300 cycles at a higher current density of 0.5 A g−1. These enhanced lithium storage performances are attributed to the combined effects of well‐dispersed tiny Ge nanoparticles, uniform carbon coating, and an abundance of defects. These factors effectively mitigate the volume expansion and lattice pulverization of Ge nanoparticles and concurrently enhance their conductivity, leading to improved overall performance in LIBs. [ABSTRACT FROM AUTHOR]

Lead‐free double perovskites with multi‐mode emission characters are highly desired for optoelectronic devices. Herein, dual‐mode thermal responses with low thermal quenching in the red emission channel and high thermal quenching in the near‐infrared (NIR) channel are achieved in a holmium‐based double perovskite (Cs2NaHoCl6). The temperature‐dependent emission is modulated by manipulating three cross relaxations of CR1 (5F4, 5I7) → (5F5, 5I6), CR2 (5S2, 5I8) → (5F5, 5I7), and CR3 (5F5, 5F5) → (5I7, 5G4) through adjusting the concentration of Ho3+. The difference in thermal response between the red and NIR emissions becomes more pronounced with a higher concentration of Ho3+ up to 100%, while the two emissions show almost the same thermal quenching behavior when the Ho3+ concentration is below 20%. To demonstrate their applications, a thermal‐responsive dual‐mode information encryption system and a NIR emitting LED with night vision capacity are fabricated using the prepared samples. This study provides a new approach for thermal quenching regulation in rare‐earth‐based lead‐free perovskites and illustrates their potential in lighting, anti‐counterfeiting, and sensing applications. [ABSTRACT FROM AUTHOR]

The development of self‐charging supercapacitor power cells (SCSPCs) has profound implications for smart electronic devices used in different fields. Here, we epitaxially electrodeposited Mo‐ and Fe‐codoped MnO2 films on piezoelectric ZnO nanoarrays (NAs) grown on the flexible carbon cloth (denoted ZnO@Mo‐Fe‐MnO2 NAs). A self‐charging supercapacitor power cell device was assembled with the Mo‐ and Fe‐codoped MnO2 nanoarray electrode and poly(vinylidenefluoride‐co‐trifluoroethylene) (PVDF‐Trfe) piezoelectric film doped with BaTiO3 (BTO) and carbon nanotubes (CNTs) (denoted PVDF‐Trfe/CNTs/BTO). The self‐charging supercapacitor power cell device exhibited an energy density of 30 μWh cm−2 with a high power density of 40 mW cm−2 and delivered an excellent self‐charging performance of 363 mV (10 N) driven by both the piezoelectric ZnO nanoarrays and the poly(vinylidenefluoride‐co‐trifluoroethylene) piezoelectric film doped with BaTiO3 and carbon nanotubes. More intriguingly, the device could also be self‐charged by 184 mV due to residual stress alone and showed excellent energy conversion efficiency and low self‐discharge rate. This work illustrates for the first time the self‐charging mechanism involving electrolyte ion migration driven by both electrodes and films. A comprehensive analysis strongly confirmed the important contribution of the piezoelectric ZnO nanoarrays in the self‐charging process of the self‐charging supercapacitor power cell device. This work provides novel directions and insights for the development of self‐charging supercapacitor power cells. [ABSTRACT FROM AUTHOR]

Quasi‐solid aqueous zinc ion batteries (AZIBs) based on flexible hydrogel electrolytes are promising substitutions of lithium‐ion batteries owing to their intrinsic safety, low cost, eco‐friendliness and wearability. However, it remains a challenge to lower the freezing point without sacrificing the fundamental advantages of hydrogel electrolytes such as conductivity and mechanical properties. Herein, an all‐around hydrogel electrolyte is constructed through a convenient energy dissipation strategy via the rapid and reversible intramolecular/intermolecular ligand exchanges between Zn2+ and alterdentate ligands. The as‐obtained hydrogel exhibits excellent mechanical properties, fatigue resistance, high Zn‐ion conductivity (38.2 mS cm−1), good adhesion (19.1 kPa), and ultra‐low freezing point (−97 °C). Due to the alterdentate ligands help to improve the zinc ion solvation structure and guide uniform Zn deposition, the Zn||Zn symmetric cells show stable plating/stripping behavior and long‐term cycle stability. The Zn||V2O5 full cells exhibit large capacity of 230.6 mAh g−1 and high capacity retention of 75.2% after 1000 cycles. Furthermore, flexible AZIBs operate stably even under extreme conditions including low temperature (−40 °C) and large bending angle (180°). The mechanically damage‐resistant hydrogel can also be utilized in flexible strain sensors. This work offers a facile strategy for developing mechanically deformation‐resistant, dendrite‐free, and environmentally adaptable AZIBs. [ABSTRACT FROM AUTHOR]

Chiral hybrid metal halides hold great potential as circularly polarized luminescence light sources. Herein, we have obtained two enantiomeric pairs of one‐dimensional hybrid chiral manganese(II) chloride single crystals, R/S‐(3‐methyl piperidine)MnCl3 (R/S‐1) and R/S‐(3‐hydroxy piperidine)MnCl3 (R/S‐2), crystallizing in the non‐centrosymmetric space group P212121. In comparison to R/S‐1, R/S‐2 single crystals not only show red emission with near‐unity photoluminescence quantum yield (PLQY) and high resistance to thermal quenching but also exhibit circularly polarized luminescence with an asymmetry factor (glum) of 2.5×10−3, which can be attributed to the enhanced crystal rigidity resulting from the hydrogen bonding networks between R/S‐(3‐hydroxy piperidine) cations and [MnCl6]4− chains. The circularly polarized luminescence activities originate from the asymmetric [MnCl6]4− luminophores induced by N−H⋅⋅⋅Cl hydrogen bonding with R/S‐(3‐hydroxy piperidine). Moreover, these samples demonstrate great application potential in circularly polarized light‐emitting diodes and X‐ray scintillators. This work shows a highly efficient photoluminescent Mn‐based halide and offers a strategy for designing multifunctional chiral metal halides. [ABSTRACT FROM AUTHOR]

Vanadium redox flow batteries (VRFBs) hold great promise for large‐scale energy storage, but their performance requires further improvement. Herein, a design is proposed for vanadium colloid flow batteries (VCFBs) that integrates the redox chemistry of polyvalent vanadium‐based colloid suspensions with dispersed conductive agents into traditional vanadium electrolytes. The redox‐active colloids combine the advantages of nanoparticle suspensions and dissolved electrolytes, exhibiting good dispersibility, fluidity, conductivity, redox reversibility, and electrochemical kinetics. By leveraging a reversible dissolution/suspension process of high‐concentration vanadium‐based colloids, the VCFBs achieved an energy density of 48 Wh L−1, nearly double that of conventional VRFBs. This work presents a rational design for homologous active material colloids to enhance the energy density of aqueous redox flow batteries, thereby advancing the potential for grid‐scale and renewable energy storage. [ABSTRACT FROM AUTHOR]

Doping Mn2+ in newly emerged lead‐free metal halides to access versatile optoelectronic applications is highly desired. However, understanding the chemical pathway of Mn2+ doping and precisely controlling it remains challenging. Here, the crucial role of the initial surface adsorption of Mn2+ in doping kinetics is demonstrated, and the adsorption step is effectively optimized by a moderate Lewis base ligand. The results show that not only the doping concentration of Mn2+ in Cs3Cu2I5 is modulated flexibly but also the produced Cs3Cu2I5:Mn2+ microcrystals exhibit tuned photoluminescence/radioluminescence properties, indicating their applicability in anti‐counterfeiting and X‐ray imaging. Systematic experimental and theoretical outcomes reveal that the moderate Lewis base ligand dually links Mn2+ (hard acid) and Cu+ (soft acid) on the matrix surface, which improves the initial surface adsorption of the dopant and further promotes the doping step. This study contributes a simple strategy for simply controlling Mn2+ doping in Cu(I)‐based halides and also opens a new avenue for understanding the fundamentals of doping dynamics in metal halide systems. [ABSTRACT FROM AUTHOR]

Despite its ultrahigh theoretical capacity and ultralow redox electrochemical potential, the practical application of lithium metal anodes is still hampered by severe dendrite growth and unstable solid electrolyte interphase (SEI). Herein, a self‐assembled lithiophilic interface (SALI) for regulating Li electroplating behavior is constructed by introducing a meticulously synthesized Ni‐bis(dithiolene)‐based molecule (NiS4‐COOH) into a hybrid fluorinated ester‐ether electrolyte. The NiS4‐COOH molecules with carboxyl functional groups can spontaneously anchor on the Li metal surface to form a SALI, whose abundant Ni‐bis(dithiolene) sites can effectively reduce the initial Li deposition overpotential and guide the subsequent uniform Li electrodeposition. Moreover, due to the interaction between the coordination unsaturated Ni atom and the negatively charged PF6−, the NiS4‐COOH additive can significantly change the ionic coordination environment in the electrolyte, which is greatly conducive to suppressing PF6− decomposition, optimizing SEI composition and accelerating Li‐ion transfer. Consequently, the NiS4‐COOH‐modified electrolyte leads to impressive electrochemical performance of Li||LiFePO4 and Li||LiNi0.8Co0.1Mn0.1O2 batteries, delivering ultrahigh Coulombic efficiencies, considerable capacity retention, and good rate performance even at high areal active material loadings. This study presents the great potential of SALIs derived from multifunctional metal‐organic hybrid electrolyte additives toward high‐specific‐energy Li metal batteries. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The kinetic process of a slow oxygen evolution reaction (OER) always constrains the efficiency of overall water electrolysis for H2 production. In particular, nonprecious metal electrodes for the OER have difficulty in possessing excellent electrocatalytic activity and stability in pH‐universal media simultaneously. In this work, urea is first used as a pore‐forming agent and active C/N source to fabricate a nanoporous NiFeCoCN medium‐entropy alloy (MEA) by high‐temperature sintering based on the nanoscale Kirkendall effect. The NiFeCoCN MEA achieves an overpotential of 432 mV at a current density of 10 mA·cm–2 and a lower Tafel slope of 52.4 mV·dec–1 compared to the IrO2/Ti electrode (58.6 mV·dec–1) in a 0.5 mol/L H2SO4 solution. In a 1 mol/L KOH solution, the NiFeCoCN MEA obtains an overpotential of 175 mV for 10 mA·cm–2 and a Tafel slope of 40.8 mV·dec–1, which is better than IrO2/Ni foam. This work proves a novel strategy to design and prepare nanoporous MEA materials with desirable C/N species, which provides promising prospects for the industrial production of H2 energy. [ABSTRACT FROM AUTHOR]

Rechargeable multivalent metal‐ion batteries (MMIBs) have garnered a surge of attention as competitive candidates for large‐scale energy storage applications owing to their high capacity, abundant resources, and good security. However, their practical implementation is still stuck at the prototype stage, mainly plagued with the lack of suitable cathode materials capable of reversible insertion/extraction of multivalent ions and the intrinsically complicated redox reaction mechanism. Recently, anionic redox chemistry has shown to be an effective strategy to increase energy density, providing a new research direction for the next generation of high‐energy rechargeable batteries. Unfortunately, anion redox chemistry has not received sufficient attention in MMIBs so far. Here, the fundamental principle and mechanism of anionic redox reactions in MMIBs are discussed and the recent advances regarding cathode materials based on cooperative cationic–anionic redox (CCAR) mechanism are summarized. Additionally, various advanced characterization techniques for studying the anionic redox process are highlighted, aiming to effectively illustrate the underlying reaction mechanism. Finally, challenges and perspectives for the future research on cationic–anionic redox chemistry in MMIBs are proposed. Insight into the significance of CCAR chemistry is provided here in MMIBs, presenting a new avenue for the development of high‐energy‐density cathode materials for MMIBs. [ABSTRACT FROM AUTHOR]

The electrocatalytic CO2 reduction reaction (CO2RR) has been considered a promising route toward carbon neutrality and renewable energy conversion. At present, most bismuth (Bi) based electrocatalysts are adopted to reduce CO2 to formate (HCOOH). However, the mechanism of different Bi nanostructures on the electrocatalytic performance requires more detailed exposition. Herein, a combined chemical replacement and electrochemical reduction process is reported to realize in situ morphology reconstruction from Bi@Bi2O3 nanodendrites (Bi@Bi2O3‐NDs) to Bi nanoflowers (Bi‐NFs). The Bi@Bi2O3‐NDs are proven to undergo a two‐step transformation process to form Bi‐NFs, aided by Bi2O2CO3 as the intermediate in KHCO3 solution. Extensive surface reconstruction of Bi@Bi2O3‐NDs renders the realization of tailored Bi‐NFs electrocatalyst that maximize the number of exposed active sites and active component (Bi0), which is conducive to the adsorption and activation of CO2 and accelerated electron transfer process. The as‐prepared Bi‐NFs exhibit a Faradaic efficiency (FEformate) of 92.3% at −0.9 V versus RHE and a high partial current density of 28.5 mA cm−2 at −1.05 V versus RHE for the electroreduction of CO2 to HCOOH. Moreover, the reaction mechanism is comprehensively investigated by in situ Raman analysis, which confirms that *OCHO is a key intermediate for the formation of HCOOH. [ABSTRACT FROM AUTHOR]

Aqueous redox flow batteries, by using redox‐active molecules dissolved in nonflammable water solutions as electrolytes, are a promising technology for grid‐scale energy storage. Organic redox‐active materials offer a new opportunity for the construction of advanced flow batteries due to their advantages of potentially low cost, extensive structural diversity, tunable electrochemical properties, and high natural abundance. In this review, we present the emergence and development of organic redox‐active materials for aqueous organic redox flow batteries (AORFBs), in particular, molecular engineering concepts and strategies of organic redox‐active molecules. The typical design strategies based on organic redox species for high‐capacity, high‐stability, and high‐voltage AORFBs are outlined and discussed. Molecular engineering of organic redox‐active molecules for high aqueous solubility, high chemical/electrochemical stability, and multiple electron numbers as well as satisfactory redox potential gap between the redox pair is essential to realizing high‐performance AORFBs. Beyond molecular engineering, the redox‐targeting strategy is an effective way to obtain high‐capacity AORFBs. We further discuss and analyze the redox reaction mechanisms of organic redox species based on a series of electrochemical and spectroscopic approaches, and succinctly summarize the capacity degradation mechanisms of AORFBs. Furthermore, the current challenges, opportunities, and future directions of organic redox‐active materials for AORFBs are presented in detail. [ABSTRACT FROM AUTHOR]

Easy and effective usage of computational resources is crucial for scientific calculations, both from the perspectives of timeliness and economic efficiency. This work proposes a bi‐level optimization framework to optimize the computational sequences. Machine‐learning (ML) assisted static load‐balancing, and different dynamic load‐balancing algorithms can be integrated. Consequently, the computational and scheduling engine of the ParaEngine is developed to invoke optimized quantum chemical (QC) calculations. Illustrated benchmark calculations include high‐throughput drug suit, solvent model, P38 protein, and SARS‐CoV‐2 systems. The results show that the usage rate of given computational resources for high throughput and large‐scale fragmentation QC calculations can primarily profit, and faster accomplishing computational tasks can be expected when employing high‐performance computing (HPC) clusters. [ABSTRACT FROM AUTHOR]

Tellurium (Te) recently attracts much attention owing to its peculiar band structure arousing high‐efficiency thermoelectricity and layered crystal structure suitable for band engineering. Herein, the temperature evolution of band structure and lattice vibration in Te single crystal are studied by mid‐and‐far infrared transmission (7500–370 and 680–30 cm−1) and Raman spectra measurements. Mid‐infrared absorption spectra confirm Te is a narrow indirect gap semiconductor, in which the direct (indirect) bandgap is about 0.333 (0.325) eV, the two upper valence bands (H4 and H5) and the third valence band (H6) being about 0.333, 0.42, and 0.76 eV, respectively, below the conduction‐band minima at 5 K. Meanwhile, the direct and indirect gaps of Te reveal non‐monotonic variation from 5 to 290 K due to the competition between electron–phonon interaction and lattice thermal expansion, which is well described by the modified Manoogian–Leclerc model. Moreover, the temperature evolution of Raman and far‐infrared transmission spectra proves there are two kinds of phonons in Te, which originates from the different thermal expansion of Te atoms along parallel and vertical directions of spiral chain. Thus, the anisotropic thermal expansion in Te is indicated and a reference for studying thermoelectricity of Te‐based optoelectronic devices is provided. [ABSTRACT FROM AUTHOR]

Aqueous organic redox flow batteries (AORFBs) are regarded as a promising candidate for grid‐scale, low‐cost and sustainable energy storage. However, their performance is restricted by low aqueous solubility and the narrow potential gap of the organic redox‐active species. Herein, a highly‐soluble organic redox pair based on pyrrolidinium cation functionalized TEMPO and extended viologen, namely Pyr‐TEMPO and [PyrPV]Cl4, which exhibits high cell voltage (1.57 V) and long cycling life (over 1000 cycles) in AORFBs is reported. The intrinsic hydrophilic nature of the pyrrolidinium group enables high aqueous solubilities (over 3.35 m for Pyr‐TEMPO and 1.13 m for [PyrPV]Cl4). Furthermore, the interaction of nitroxyl radicals with water is observed, which may be helpful to prevent collision‐induced side reactions or structure decomposition. Notably, the assembled AORFBs realize a high energy density of 16.8 Wh L‐1 and a peak power density of 317 mW cm‐2. The evidence is provided to clarify the capacity degradation mechanism of TEMPO/viologen AORFB systems by a series of comprehensive characterizations. Furthermore, the reversible consumption and re‐generation of the nitroxyl radicals upon charging and discharging are well understood. This work presents effective electrochemical and spectroscopic approaches to clarify the redox chemistry and capacity degradation mechanism of radical incorporating AORFB systems. [ABSTRACT FROM AUTHOR]

The chemical transformation of carbon dioxide (CO2) has been considered as a promising strategy to utilize and further upgrade it to value‐added chemicals, aiming at alleviating global warming. In this regard, sustainable driving forces (i.e., electricity and sunlight) have been introduced to convert CO2 into various chemical feedstocks. Electrocatalytic CO2 reduction reaction (CO2RR) can generate carbonaceous molecules (e.g., formate, CO, hydrocarbons, and alcohols) via multiple‐electron transfer. With the assistance of extra light energy, photoelectrocatalysis effectively improve the kinetics of CO2 conversion, which not only decreases the overpotentials for CO2RR but also enhances the lifespan of photo‐induced carriers for the consecutive catalytic process. Recently, rational‐designed catalysts and advanced characterization techniques have emerged in these fields, which make CO2‐to‐chemicals conversion in a clean and highly‐efficient manner. Herein, this review timely and thoroughly discusses the recent advancements in the practical conversion of CO2 through electro‐ and photoelectrocatalytic technologies in the past 5 years. Furthermore, the recent studies of operando analysis and theoretical calculations are highlighted to gain systematic insights into CO2RR. Finally, the challenges and perspectives in the fields of CO2 (photo)electrocatalysis are outlined for their further development. [ABSTRACT FROM AUTHOR]

Concentrating on the high frequency aerospace demand of solid‐state power amplifier (SSPA), this paper presents the methodology and key technique of a W‐band 3‐W SSPA that achieves high efficiency while maintaining excellent reliability capability. An improved Magic‐T power combiner is utilized to achieve high output power, and eliminate the influence of the parallel end‐stage gallium‐nitride high‐electron‐mobility‐transistor (GaN HEMT) PAs by its good isolation performance. The SSPA's millimetre‐wave circuit is implemented by three stages of amplifier, to realized more than 30‐dB power gain. The power‐supply circuit based on the two‐transistor forward topology is proposed for voltage converting and output serious sequence controlling. The SSPA is fabricated and measured, achieving 33‐dBm to 34.1‐dBm output power within the frequency range of 92–96 GHz, with the power gain of 31–32 dB, and peak efficiency of 7.1%, respectively. The proposed SSPA shows competitive performance for space application. [ABSTRACT FROM AUTHOR]

In this paper, for the first time, a rationally designed strategy for synthesis of Co nanoparticles encapsulated by boron and nitrogen co‐doped carbon nanosheets (CNs), namely B, N‐Co/CNs, as highly efficient electrocatalyst for oxygen reduction reaction (ORR) is demonstrated. The generated Co nanoparticles not only create well‐defined heterointerfaces with high conductivity to overcome the poor ORR activity but also promote the formation of robust graphitic carbon. The co‐existence of boron and nitrogen atoms can increase the highest occupied molecular orbital energy of sp2 hybridization, activating π electrons in graphitic CNs, thereby enhancing the activity of the catalyst. The B, N‐Co/CNs exhibit a comparable half‐wave potential (E1/2 = 0.83 V) to that of commercial Pt/C catalyst (E1/2 = 0.85 V) with a larger current density for ORR. Importantly, the homemade disposable Zn‐air battery (ZAB) is able to deliver excellent performance, including a peak power density of 93.93 mW cm−2 and a specific capacity of 727.5 mAh g−1, outperforming the Pt/C catalyst. The findings highlight a new guideline for constructing B, N‐Co/CNs catalyst with a rationally designed structure toward superior property for advanced metal‐air cathode materials. [ABSTRACT FROM AUTHOR]

To manipulate the electrical and optical properties of 2D materials via engineering their phases and crystallinity is of great significance for the construction of nanodevices with versatile functions. Herein, the controllable transformation of semimetallic gray arsenene nanoflakes into semiconducting vitreous arsenene nanoflakes via a wet chemistry vitrification method is reported. Experimental studies and theoretical simulations reveal that the vitrification of gray arsenene nanoflakes is attributed to the consumption of arsenic atoms by aqueous HF via the trigger of dissolved oxygen, resulting in a significant variation of band structure rendered by the formation of atomic structure disorderliness and arsenic atom defects/vacancies. Unlike the semimetallic features of pristine gray arsenene nanoflakes, the as‐prepared vitreous arsenene nanoflakes exhibit a strong photoluminescence peak centered at 635 nm corresponding to an optical band gap of 1.95 eV, and the field‐effect transistors based on vitreous arsenene nanoflakes also exhibit definitely p‐type semiconducting characteristics with a carrier mobility of ≈159.1 cm2 V−1 s−1. The wet chemistry induced vitrification of gray arsenene nanoflakes presents an efficient strategy to regulate the electrical and optical properties of arsenene nanoflakes, providing new insights for the interface and band structure engineering of 2D nanomaterials. [ABSTRACT FROM AUTHOR]

Transition metal single‐atom catalysts (SACs) are currently a hot area of research in the field of electrocatalytic oxygen reduction reaction (ORR). In this review, the recent advances in transition metal single‐atom supported by 2D materials as catalysts for ORR with high performance are reported. Due to their large surface area, uniformly exposed lattice plane, and adjustable electronic state, 2D materials are ideal supporting materials for exploring ORR active sites and surface reactions. The rational design principles and synthetic strategies of transition metal SACs supported by 2D materials are systematically introduced while the identification of active sites, their possible catalytic mechanisms as well as the perspectives on the future of transition metal SACs supported by 2D materials for ORR applications are discussed. Finally, according to the current development trend of ORR catalysts, the future opportunities and challenges of transition metal SACs supported by 2D materials are summarized. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal anodes have been proposed as a promising candidate for high‐energy‐density electrode materials in secondary batteries. However, the dendrite growth and unstable electrode–electrolyte interfaces during Li plating/stripping are fatal to their practical applications. Herein, the construction of 3D porous Au/Cu nanoscaffold prepared via a convenient template‐sacrificed hot fusion construction method and a nanoseed modification process as an effective Li metal hosting material are proposed. The Au/Cu nanoscaffold can spatially guide uniform deposition of Li metal free from the growth of Li dendrites due to the homogenous Li+ ion flux and negligible nucleation overpotential. Moreover, the Cu skeleton can relieve volume change and stabilize local current density during cycling processes. Benefiting from these advantages, the symmetric cells based on self‐supported Li‐filled Au/Cu (Li‐Au/Cu) nanoscaffold electrodes present highly stable Li plating/stripping for more than 1000 h with a low voltage hysteresis less than 90 mV and a long lifespan over 1300 h at 1.0 mA cm–2 in carbonate‐based electrolytes. Impressively, the Li‐Au/Cu nanoscaffold||LiFePO4 full cells also exhibit exceptional cycling stability and rate performance. This work provides a promising strategy to construct dendrite‐free lithium metal anodes toward high‐performance lithium metal batteries. [ABSTRACT FROM AUTHOR]

Rechargeable non‐lithium metal–sulfur batteries (MSBs) have gained tremendous attention because of their merits, including a high theoretical capacity, remarkable energy density, and low cost. However, the detrimental issues encountered by non‐lithium MSBs, such as polysulfide shuttle effects, volume expansion and the low electrical conductivity of elemental sulfur, and the serious side reactions between metal anodes and electrolytes, severely restrict their practical applications. To circumvent these issues, numerous effective strategies have been explored and utilized. In this review, the intractable obstacles that prevent the application of non‐lithium MSBs are first summarized. Recent pioneering studies on rechargeable non‐lithium MSBs are reported and discussed in terms of material design, fabrication methods, and electrochemical performance. The emerging characterization techniques used to reveal the working mechanisms of non‐lithium MSBs and the advantages of elaborately designed structures are highlighted. Finally, the remaining issues and possible future areas of research for practical applications are discussed. [ABSTRACT FROM AUTHOR]

Rechargeable magnesium batteries (RMBs) based on metal Mg anodes have shown great potential owing to the abundant natural resources, high volumetric capacity, and low safety hazard. Nevertheless, the development of RMBs is hampered by the sluggish kinetics of Mg2+ diffusion and the limited cyclability of cathode materials. Herein, nonstoichiometric copper selenide (Cu2–xSe) are synthesized via a solution‐based method and exploited as a durable cathode material based on ionic displacement mechanism for RMBs. The copper ions in the Se2− based sub‐lattices are reversibly exchanged by Mg2+ ions without causing lattice collapse. Owing to the same face‐centered cubic Se2− sub‐lattices and similar unit cell size of Cu2–xSe and MgSe, the energy barrier for lattice reconstruction during cycling processes is very low, significantly improving the rate performance, structural stability, and cycle life of the Cu2–xSe cathode. Moreover, metal Cu is in situ generated during discharging, thus greatly facilitating electron transport. Comprehensive characterizations confirm that the Cu2–xSe cathode undergoes reversible copper ion extrusion/reinjection during the discharge−charge steps. This work suggests the great potential for exploring high‐performance electrode materials based on ionic displacement mechanism for advanced multivalent‐ion secondary batteries. [ABSTRACT FROM AUTHOR]

Herein, the influence of equal channel angular pressing (ECAP) routes, i.e., A and Bc, on the microstructure and texture evolution of a Mg–3.7Al–0.7Zn–0.8Sn–0.4Mn (wt%) alloy is investigated by scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and X‐ray diffraction (XRD). It is found that with increasing the number of ECAP passes, the area fraction of the dynamically precipitated secondary‐phase particles increases, whereas particle size becomes larger. After four and six passes of ECAP via route A, shear deformation induced by ECAP promotes the incline of c‐axes toward extrusion direction (ED). The optimum room temperature (RT) mechanical properties (yield strength of ≈225 MPa, ultimate tensile strength of ≈312 MPa, and elongation to fracture of ≈31.9%) are obtained after four passes of ECAP at 200 °C via route A. The improved strength results from fine dynamic recrystallization (DRX)/ed grains, nanoscale secondary‐phase particles, and basal texture. Herein, it is indicated that Mg–Al–Zn–Sn alloys have great potential as low‐cost high‐strength‐ductility wrought Mg alloys. [ABSTRACT FROM AUTHOR]

GridMol is a "one‐stop" platform for molecular structure building, scientific computing, and molecular visualization aided by a high‐performance computing environment. GridMol version 2.0 introduces two unique features: the first is fragment‐based linear‐scaling quantum chemistry methods, such as molecular fractionation with conjugate caps and fragment molecular orbital methods; the second is that GridMol enables users to visualize molecular geometries along a geometry optimization and an intrinsic reaction coordinate calculation. Compared with version 1.0, fragment‐based linear‐scaling quantum chemistry methods implemented in GridMol version 2.0 can be used as a useful tool for performing quantum calculations for large molecular systems to explore the mechanisms involved in protein‐ligand or targeted drug interactions. [ABSTRACT FROM AUTHOR]

During the summer of 2018, one Syringa reticulata plant showing witches' broom and small leaves was observed in Beijing, China. Molecular diagnostic tools and electron microscopic cell observation were used to detect the possible pathogen of this disease. As a result, the phytoplasma in the symptomatic S. reticulata tree was confirmed by amplifying the 16S rRNA gene using the phytoplasma‐specific universal primer pair R16mF2/R16mR1 and observation with transmission electron microscopy. The rp and tuf genes of the phytoplasma were also cloned and sequenced as the 16S rRNA gene. Sequence and phylogenetic analyses of the 16S rRNA, rp and tuf genes indicated that the phytoplasma associated with S. reticulata witches' broom (SrWB) disease belonged to the 16SrV‐B subgroup, and it was closely related to the 16SrV‐B subgroup phytoplasma strain jujube witches' broom, which causes serious disease of jujube fruit trees in China. This study shows the S. reticulata tree as a new host of a phytoplasma belonging to the 16SrV‐B subgroup in China. [ABSTRACT FROM AUTHOR]

Arsenene has recently emerged as a promising new two‐dimensional material for biomedical applications because of its excellent optical and electronic properties. Herein, novel 2D arsenene nanosheets were synthesized and shown to be effective against NB4 promyelocytic leukaemia (APL) cells (82 % inhibition) as well as inducing apoptosis while showing no toxicity towards normal cells. The high zeta potential, small size, and the planar structure were crucial to the toxicity of the materials. Label‐free proteomic profiling analysis suggested that arsenene affected nuclear DNA replication, nucleotide excision repair, and pyrimidine metabolism pathways by downregulating the DNA polymerases POLE, POLD1, POLD2, and POLD3. Mass spectrometric studies showed that arsenene bound mainly to nuclear nucleotide acid binding proteins in NB4 cells and further cellular fluorescence studies revealed that the arsenene destroyed the nuclei. In vivo toxicity tests in mice also indicated the physiological biosafety of arsenene. [ABSTRACT FROM AUTHOR]

NiS2 nanoparticles (NPs)‐modified CdS nanowires (NWs) (NiS2/CdS) with varying amount of NiS2 were synthesized via a two‐step approach and characterized for sustainable hydrogen evolution. They showed much higher activity than pristine CdS NWs or NiS2 NPs, with the optimal hydrogen production rate reaching 14.49 mmol⋅h−1⋅g−1 for 40%‐NiS2/CdS with lactic acid as sacrificial agent. Under optimal conditions, hydrogen generation rate of 52.88 μmol⋅h−1⋅g−1 was achieved using single cellulose as sacrificial agent. Photoelectrochemical (PEC) properties of the NiS2/CdS nanocomposites were investigated to gain a better understanding of the mechanism behind the enhanced photocatalytic hydrogen evolution reaction (HER) activity. Furthermore, ultrafast transient absorption (TA) spectroscopy was also employed to investigate the charge carrier dynamics, revealing an exciton lifetime approximately four times shorter in 40%‐NiS2/CdS nanocomposite compared to pristine CdS NWs. These results suggest efficient charge transfer from CdS to NiS2. A possible mechanism for enhanced hydrogen production over NiS2/CdS nanocomposite is proposed. [ABSTRACT FROM AUTHOR]

Aim: Recent studies have suggested that oral bacteria induce systemic inflammation through the alteration of gut microbiota. We examined the relationship between oral and gut microbiota to evaluate the transition of oral bacteria to the gastrointestinal tract. Methods: Oral samples from subgingival plaque and tongue‐coating and fecal samples were collected from 29 elderly subjects (age, 80.2 ± 9.1 years) and 30 adults (age, 35.9 ± 5.0 years). Genomic DNA was extracted from all samples, and DNA sequencing of bacterial 16S rRNA genes was performed for microbiota analysis. UniFrac distances were calculated to evaluate the similarity between microbial communities. Results: Unweighted UniFrac distance indicated that the elderly group had a higher similarity between fecal and subgingival plaque microbiota than the adult group. Indeed, some bacterial taxa found in oral samples had a significantly higher prevalence in the feces of the elderly group than in that of the adult group. Conclusions: The prevalence of oral bacterial transition to gut may be higher in the elderly than in adults, expecting that oral health care in the elderly will affect their gut microbiota composition and consequently promote human health. [ABSTRACT FROM AUTHOR]

CH3NH3PbBr3 perovskite quantum dots (PQDs) are synthesized by using four different linear alkyl phosphonic acids (PAs) in conjunction with (3‐aminopropyl)triethoxysilane (APTES) as capping ligands. The resultant PQDs are characterized by means of XRD, TEM, Raman spectroscopy, FTIR spectroscopy, UV/Vis, photoluminescence (PL), time‐resolved PL, and X‐ray photoelectron spectroscopy (XPS). PA chain length is shown to control the PQD size (ca. 2.9–4.2 nm) and excitonic absorption band positions (λ=488–525 nm), with shorter chain lengths corresponding to smaller sizes and bluer absorptions. All samples show a high PL quantum yield (ca. 46–83 %) and high PL stability; this is indicative of a low density of band gap trap states and effective surface passivation. Stability is higher for smaller PQDs; this is attributed to better passivation due to better solubility and less steric hindrance of the shorter PA ligands. Based on the FTIR, Raman, and XPS results, it is proposed that Pb2+ and CH3NH3+ surface defects are passivated by R−PO32− or R−PO2(OH)−, whereas Br− surface defects are passivated by R−NH3+ moieties. This study establishes the combination of PA and APTES ligands as a highly effective dual passivation system for the synergistic passivation of multiple surface defects of PQDs through primarily ionic bonding. PDQ synthesis of PQDs: The passivation strategy reported herein is to use organic molecules linear alkyl phosphonic acids (PAs) and (3‐aminopropyl)triethoxysilane (APTES) as ligands. The PAs and APTES produce R−PO2(OH)−, R−PO32−, and R−NH3+ to effectively passivate the charged surface defects of CH3NH3PbBr3 perovskite quantum dots (PQDs) due to dangling bonds related to species such as MA+, Pb2+ and X−, respectively (see figure). [ABSTRACT FROM AUTHOR]

2,4,6‐Tris(pyridin‐4‐yl)‐1,3,5‐triazine (tpt), as an organic molecule with an electron‐deficient nature, has attracted considerable interest because of its photoinduced electron transfer from neutral organic molecules to form stable anionic radicals. This makes it an excellent candidate as an organic linker in the construction of photochromic complexes. Such a photochromic three‐dimensional (3D) metal–organic framework (MOF) has been prepared using this ligand. Crystallization of tpt with Cd(NO3)2·4H2O in an N,N‐dimethylacetamide–methanol mixed‐solvent system under solvothermal conditions afforded the 3D MOF poly[[bis(nitrato‐κ2O,O′)cadmium(II)]‐μ3‐2,4,6‐tris(pyridin‐4‐yl)‐1,3,5‐triazine‐κ3N2:N4:N6], [Cd(NO3)2(C18H12N6)]n, which was characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis and single‐crystal X‐ray diffraction. The X‐ray diffraction crystal structure analysis reveals that the asymmetric unit contains one independent CdII cation, one tpt ligand and two coordinated NO3− anions. The CdII cations are connected by tpt ligands to generate a 3D framework. The single framework leaves voids that are filled by mutual interpenetration of three independent equivalent frameworks in a fourfold interpenetrating architecture. The compound shows a good thermal stability and exhibits a reversible photochromic behaviour, which may originate from the photoinduced electron‐transfer generation of radicals in the tpt ligand. A fourfold interpenetrating cadmium(II) metal–organic framework, which has been prepared using the 2,4,6‐tris(pyridin‐4‐yl)‐1,3,5‐triazine ligand, exhibits prominent photochromic behaviour upon UV–Vis light irradiation. [ABSTRACT FROM AUTHOR]

Summary: Parkinson's disease (PD) is a common degenerative neurological disease leading to a series of familial, medical, and social problems. Although it is known that the major characteristics of PD pathophysiology are the dysfunction of basal ganglia due to injury/loss of dopaminergic neurons in the substantia nigra pars compacta dopaminergic and exhaustion of corpus striatum dopamine, therapeutic modalities for PD are limited in clinical settings up to date. It is of utmost importance to better understand PD pathophysiology and explore new solutions for this serious neurodegenerative disorder. Our recent work and those of others suggest that the delta‐opioid receptor (DOR) is neuroprotective and serves an antiparkinsonism role in the brain. This review summarizes recent progress in this field and explores potential mechanisms for DOR‐mediated antiparkinsonism. [ABSTRACT FROM AUTHOR]

A novel compatibilizer with high grafting degree (GD%) of maleic anhydride (MA) onto liquid polybutadiene (LPB) was synthesized via a solution method, in particular, very low gel rate was produced by the synergetic effects of acetanilide and epoxy resin (EP), and the GD% was improved by adding the EP resin and acetanilide. The structure and thermal stability of the MA‐grafted‐liquid polybutadiene (LPB‐g‐MA) were characterized by acid base titrations, FTIR, and TGA techniques. The results showed that both MA and EP resin have been grafted onto the macromolecular chains of LPB with a good thermal stability. Then, it was used as compatibilizer in short aramid fiber (AF) reinforcing natural rubber (NR)/carbon black (CB). The synthetic compatibilizer (LPB‐g‐MA) enhanced the interfacial interaction between the fiber and the rubber matrix with a lower swelling degree and lower peak of loss factor, and the mechanical properties including tensile strength, tensile modulus 100%, tear strength and elongation at break of the final composites increased with the increase of m (E51)/m (LPB). AF and CB had a synergistic effect to reinforce the properties of NR. The dynamic stiffness of the rubber was obviously improved by the short AF, especially in the presence of the compatibilizer. POLYM. COMPOS., 39:E2006–E2015, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Abstract: Organic‐inorganic hybrid perovskites are highly promising materials for photovoltaic applications, yet their rapid degradation remains a significant challenge. Here, three highly stable methylammonium lead iodide (MAPbI3) perovskite films modified with polyethylenimines (PEIs) of different molecular weights (Mw=600, Mw=10000 and Mw=70000) were successfully obtained. The PEIs were used as an additive in the perovskite to determine their influences on the structure, film quality, and performance of the perovskite. The perovskite films modified with PEIs showed excellent stability, when studied over 20 days under ambient air conditions with a medial humidity of 60%. The results of XRD, UV‐Vis absorption and fluorescence lifetime measurements showed that the PEI could not substitute for MA within the perovskite crystal lattice. The solar power conversion efficiency (PCE) η of the pristine perovskite film and those modified with PEI (Mw=600), PEI (Mw=10000) and PEI (Mw=70000) were 9.69%, 6.84%, 6.43% and 6.94%, respectively. Even though the PCE is lower for the PEI‐modified solar cells, their stability is substantially improved. The improved stability is attributed to PEI‐H+ cations in the grain boundary of the perovskites, preventing them from direct contact with water molecules that otherwise cause fast degradation. This demonstrates that PEI modification is a simple and powerful strategy for stabilizing perovskite films. [ABSTRACT FROM AUTHOR]

Abstract: Here, a protocol for robust preparation of an atomic concatenated Greenberger–Horne–Zeilinger (C‐GHZ) state via shortcuts to adiabaticity (STA) is proposed. The devices for implementing the protocol consist of atoms, cavities, and the optical fibers, which are feasible with current technology. The atoms are trapped in the separated cavities allowing individual control over each atom with classical fields. STA helps to design Rabi frequencies of classical fields so that the atoms can be driven from the initial states to the target states. The numerical simulations show that the protocol holds robustness against atomic spontaneous emissions and photonic leakages. Thus, the protocol may be realized by experiments in the near future. [ABSTRACT FROM AUTHOR]

Abstract: Metal oxide‐based nanomaterials are widely studied because of their high‐energy densities as anode materials in lithium‐ion batteries. However, the fast capacity degradation resulting from the large volume expansion upon lithiation hinders their practical application. In this work, the preparation of walnut‐like multicore–shell MnO encapsulated nitrogen‐rich carbon nanocapsules (MnO@NC) is reported via a facile and eco‐friendly process for long‐cycling Li‐ion batteries. In this hybrid structure, MnO nanoparticles are uniformly dispersed inside carbon nanoshells, which can simultaneously act as a conductive framework and also a protective buffer layer to restrain the volume variation. The MnO@NC nanocapsules show remarkable electrochemical performances for lithium‐ion batteries, exhibiting high reversible capability (762 mAh g−1 at 100 mA g−1) and stable cycling life (624 mAh g−1 after 1000 cycles at 1000 mA g−1). In addition, the soft‐packed full batteries based on MnO@NC nanocapsules anodes and commercial LiFePO4 cathodes present good flexibility and cycling stability. [ABSTRACT FROM AUTHOR]

PSMD7, a 19S proteasome subunit, is overexpressed in most carcinoma cells. It forms a dimer with PSMD14 that functions in the removal of attached ubiquitin chain. However, there is little knowledge about the cellular mechanism of PSMD7 and its exact biological function, especially in cancer cells. In this study, we explored the role of PSMD7 in proliferation, cell cycle, apoptosis, and proteasomal proteolysis in the esophageal squamous cell carcinoma (ESCC) cell line EC9706. Our results showed that PSMD7 was highly expressed in ESCC cells. Downregulation of PSMD7 by lentivirus‐mediated shRNA led to decreased proliferation, increased cell apoptosis, and reduced proteasomal function. Notably, lower expression level of mTOR and p70S6K and suppressed activity of mTOR/p70S6K pathway were detected after PSMD7 downregulation. By contrast, increased expression of p‐mTORSer2448 and p‐p70S6KThr421/Ser424 was discovered upon PSMD7 overexpression in Het‐1A cells. Furthermore, PSMD7 downregulation contributed to decelerated tumor growth, inhibition of proteasomal function, induced cell apoptosis and attenuated activity of mTOR/p70S6K pathway in vivo. These findings suggest that PSMD7 and the mTOR/p70S6K pathway may be a promising candidate for developing therapies for ESCC. [ABSTRACT FROM AUTHOR]

Abstract: The surface of CH3NH3PbBr3 perovskite nanocrystals (PNCs) plays a critical role in determining their optical properties and stability. The introduction of capping ligands can enhance photoluminescence (PL), reduce non‐radiative recombination, and improve stability. Here, we report a facile synthesis of CH3NH3PbBr3 PNCs with strong and highly stable green PL using melamine (Mela) as a simple and low‐cost capping ligand. The resulting CH3NH3PbBr3/Mela PNCs have cubic phase crystal structure with an average particle size of 5.29±0.06 nm. The optical absorption and PL of the CH3NH3PbBr3/Mela PNCs with narrow bandwidth can be tuned within the visible region, and the PL quantum yield (QY) reached 52.3% compared to 0.4% the pristine CH3NH3PbBr3 PNCs. A synergistic effect between NH3+ and the electron‐rich nitrogen atoms together with p‐p stacking capacity, likely contributes to enhance the PL by effectively passivating of the trap states of PNCs. Furthermore, melamine‐capped PNCs show high stability in protic solvents as a result of the steric bulkiness of the triazine rings, owing to the planar structure together with hydrogen bonding of melamine, which prevents solvent molecules from reaching and reacting with the core of PNCs. This study demonstrates a simple and effective approach for stabilizing PNCs for potential applications such as solar cells and LEDs. [ABSTRACT FROM AUTHOR]

Abstract: The worldwide unrestrained emission of carbon dioxide (CO2) has caused serious environmental pollution and climate change issues. For the sustainable development of human civilization, it is very desirable to convert CO2 to renewable fuels through clean and economical chemical processes. Recently, electrocatalytic CO2 conversion is regarded as a prospective pathway for the recycling of carbon resource and the generation of sustainable fuels. In this review, recent research advances in electrocatalytic CO2 reduction are summarized from both experimental and theoretical aspects. The referred electrocatalysts are divided into different classes, including metal–organic complexes, metals, metal alloys, inorganic metal compounds and carbon‐based metal‐free nanomaterials. Moreover, the selective formation processes of different reductive products, such as formic acid/formate (HCOOH/HCOO−), monoxide carbon (CO), formaldehyde (HCHO), methane (CH4), ethylene (C2H4), methanol (CH3OH), ethanol (CH3CH2OH), etc. are introduced in detail, respectively. Owing to the limited energy efficiency, unmanageable selectivity, low stability, and indeterminate mechanisms of electrocatalytic CO2 reduction, there are still many tough challenges need to be addressed. In view of this, the current research trends to overcome these obstacles in CO2 electroreduction field are summarized. We expect that this review will provide new insights into the further technique development and practical applications of CO2 electroreduction. [ABSTRACT FROM AUTHOR]