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Soybean, one of the major food and fodder crops, yield is significantly reduced by different abiotic and biotic stresses, and salinity is one of the major abiotic stresses. The research objective of this study was to investigate the effect of foliar application of potassium chloride and potassium sulfate fertilizers at the early growth stage of soybean under medium (6 dS/m) and high (12 dS/m) salinity stresses. The effect of fertilizer application was measured on the bases of plant growth, levels of antioxidant activities, total polyphenol, flavonoid, chlorophyll, and carotenoid contents. Potassium sulfate showed better positive effect on the antioxidant activities, polyphenol, flavonoid, carotenoid, and chlorophyll contents compared to those of potassium chloride although the contribution was not noteworthy in comparison to the fertilizer unsprayed plants. The results of this study implied that foliar applications of 2.5% potassium fertilizers could not help reduce the negative effect of salinity stress at the early stage of soybean growth. This study suggests further researches using different concentrations of fertilizers at different plant growth and development stages. [ABSTRACT FROM AUTHOR]

Peanut shell; a byproduct of an important leguminous crop, peanut; is a potential source of different functional compounds. Antioxidant activities, secondary metabolites and amino acid contents in peanut shells of six Korean cultivars were studied in the present study. Peanut shells showed remarkable antioxidant potentials with high amounts of total polyphenol (428.1–739.8 µg gallic acid equivalents/g), flavonoid (142.6–568.0 µg quercetin equivalents/g), and amino acid (5.76–34.56 mg/g) contents. 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), superoxide dismutase (SOD)-like activity, and reducing power potential of the peanut shells were considerable. The results suggest that the shells of Korean peanut cultivars could be a potential source of natural antioxidants and functional compounds for various industrial uses including cosmetics. [ABSTRACT FROM AUTHOR]

Ethyl pyruvate (EP) is a simple aliphatic ester of pyruvic acid and has been shown to have protective properties, which have been attributed to its anti-inflammatory, anti-oxidative, and anti-apoptotic functions. In an effort to develop better derivatives of EP, we previously synthesized DEOPA (N,N-diethyl-2-oxopropanamide, a novel isoster of EP) which has greater neuroprotective effects than EP, probably due to its anti-inflammatory and anti-excitotoxic effects. In the present study, we synthesized 3 DEOPA derivatives, in which its diethylamino group was substituted with diisopropylamino, dipropylamino, or diisobutylamino groups. Among them, DIPOPA (N,N-diisopropyl-2-oxopropanamide) containing diisopropylamino group had a greater neuroprotective effect than DEOPA or EP when administered intravenously to a rat middle cerebral artery occlusion (MCAO) model at 9 h after MCAO. Furthermore, DIPOPA had a wider therapeutic window than DEOPA and a marked reduction of infarct volume was accompanied by greater neurological and behavioral improvements. In particular, DIPOPA exerted robust anti-inflammatory effects, as evidenced by marked suppressions of microglia activation and neutrophil infiltration in the MCAO model, in microglial cells, and in neutrophil-endothelial cocultures at lower concentration, and did so more effectively than DEOPA. In particular, DIPOPA remarkably suppressed neutrophil infiltration into brain parenchyma, and this effect was attributed to the expressional inhibitions of cell adhesion molecules in neutrophils of brain parenchyma and in circulating neutrophils via NF-κB inhibition. Together, these results indicate the robust neuroprotective effects of DIPOPA are attributable to its anti-inflammatory effects and suggest that DIPOPA offers a potential therapeutic means of ameliorating cerebral ischemic injury and other inflammation-related pathologies. [ABSTRACT FROM AUTHOR]

Abstract Pt-based catalysts are suffering from the intrinsic high cost and poor stability for practical use in fuel cells. We develop a free-standing fabric type Pt-free high-performance oxygen reduction reaction (ORR) catalyst, consisting of N, Fe-codoped carbon nanofibers and graphene (N/Fe-CG) hybrids. Electrospinning is used to synthesize the free-standing fabric catalysts. Incorporation of graphene into the nanofiber structure greatly increases the electrical conductivity and catalytic surface area. X-ray photoelectron spectroscopy (XPS) analysis provides evidence that Fe-N 4 active centers are possibly formed in the catalyst, as is confirmed by electrochemical tests also. Compared to commercial Pt/C, our N/Fe-CG exhibits a similar level of catalytic activity but superior stability and methanol tolerance in both alkaline and acidic media, making it a good candidate for an ORR electrocatalyst in energy storage/conversion and other relevant applications. Graphical abstract fx1 Highlights • N, Fe-codoped free-standing carbon fabric ORR catalyst is successfully developed • The catalyst shows excellent catalytic properties in both alkaline and acidic media • Sample with N, Fe-codoping reveals better performance than single atom doped samples • FeN 4 complex formation is confirmed by electrochemical performance and XPS analysis [ABSTRACT FROM AUTHOR]

To date, lithium-oxygen batteries (LOBs) using porous carbon materials as the air cathode have been widely studied. However, a fundamental issue of carbon electrode still remains; the carbon surface is unstable and is highly reactive in contact with Li 2 O 2 , resulting in the formation of irreversible byproducts ( e.g. , Li 2 CO 3 ). To address this issue, we investigated the use of surface protection layers for improving the cycling stability of porous carbon-based LOB cathode. We employed atomic layer deposition (ALD) for conformal coating of two types of overlayers (In 2 O 3 and TiN), i.e. , oxide and nitride thin film, on an electrospun carbon nanopaper (CNp) membrane. The LOB cell with In 2 O 3 -coated CNp exhibited much enhanced cycling performance (over 140 cycles) compared with pristine CNp and TiN-coated CNp as control samples (less than 60 cycles for both cases). To further improve cell efficiency by reducing overpotentials, the surface of In 2 O 3 -coated CNp electrode was functionalized by catalytic RuO x nanoparticles, which enables stable and complete discharging and recharging reactions below 4.2 V for an extended period of 165 cycles. Interestingly, after each discharge, nanosheet-like Li 2 O 2 growth was observed on In 2 O 3 -coated CNps, which is advantageous for enhanced cycle life. This work demonstrates that use of a free-standing, high surface area carbon membrane, that is conformally encapsulated by a highly conductive and stable oxide protection layer, is essential for enhanced Li-O 2 cell performance by preventing direct contact between underneath carbon and electrolyte. [ABSTRACT FROM AUTHOR]

With the rapid development of portable/wearable electronic devices, the demand for highly efficient and sustainable self-powered systems to support their off-grid operation has risen considerably. Recently, metal halide perovskites (MHPs) have been suggested as promising materials for energy harvesting and storage devices because of their excellent optoelectronic, ferro/piezoelectric, and ion migration properties. However, the high toxicity and poor physicochemical stability of MHPs hamper their practical application. Herein, for the first time, the potential of methylammonium tin halide (MA 2 SnX 6 ; X = Cl, Br, and I) double perovskite thin films for high-efficiency self-charging power units (SPUs) is elucidated by virtue of their high stability in air. To this end, the integration of an MA 2 SnCl 6 -based piezoelectric nanogenerator (PENG) with a lithium metal battery (LMB), which also uses an MA 2 SnCl 6 -based thin film as the cathode, is demonstrated. The MA 2 SnCl 6 -based PENG exhibited a high output power density of 7.33 μW cm−2 and an excellent mechanical durability. Furthermore, MA 2 SnCl 6 as a cathode in LMB recorded the highest specific capacity of 589.98 mAh g−1. A 1 nm-thick Al 2 O 3 coating on the MA 2 SnCl 6 surface improved the capacity retention from 16.9 % to 75.1 % for 100 cycles, indicating its stable performance. The MA 2 SnCl 6 -based LMB is charged by the MA 2 SnCl 6 -based PENG and utilized as an SPU for operating various small-scale electronics (humidity meter, calculator, and LED). This work not only demonstrates the feasibility of MHPs toward high-capacity batteries and energy harvesters but also provides insights into the general design principles of MHP-based devices. [Display omitted] • Lead-free MA 2 SnX 6 double halide perovskite as an active material for efficient energy harvester and storage device. • MA 2 SnCl 6 -based PENG exhibited a high output power density of 7.33 μW cm−2. • MA 2 SnCl 6 -based Li metal battery recorded the highest specific capacity of 589.98 mAh g−1. • Improved capacity retention of MA 2 SnCl 6 -based LMB by the Al 2 O 3 surface coating. • Realizing of self-charging power unit by combing MA 2 SnCl 6 -based Li metal battery and PENGs. [ABSTRACT FROM AUTHOR]

The configuration of reinforced composite membrane (RCM), composed of porous polytetrafluoroethylene (PTFE) as a mechanical reinforcement and perfluorosulfonic acid (PFSA) as a proton conductive polymer, has gained a large interest due to its promisingly high performance for polymer electrolyte membrane (PEM) fuel cells. However, the inaccessible polymeric nanocomposites in preparing RCMs are still faced with critical challenges associated with immiscible interactions between hydrophilic sulfonate groups in PFSA and the hydrophobic nanoporous PTFE matrix. Herein, we report a well-refined and facile fabrication strategy for producing a cross-aligned PTFE (CA-PTFE) framework. The electric-field guided electrospinning enables the creation of unique micron-scale, grid-type PTFE matrix, which is synthesized by annealing of electrospun conjugated polymers, resulting in the removal of carrier polymer and the formation of continuous fibrious structure via fusion of PTFE particles. The CA-PTFE RCM embodying uniformly impregnated PFSA in a grid-type PTFE matrix, facilitates hydration of the membranes, with minimal swelling and efficient diffusion of protons through concentrated sulfonate groups. The CA-PTFE RCM adopted cell showed outstanding fuel cell currents during both low and high humidity operation, with a current density of 1.38 A cm−2 at 0.6 V and maximum power density of 0.85 W cm−2 under RH 100% condition. Furthermore, the CA-PTFE RCM was able to achieve a long-lasting single-cell operation with a significantly low hydrogen crossover (less than 5 mA cm−2 at 0.4 V) even after 21,000 wet/dry cycles, which surpasses the standard of membrane durability for transportation application. The rational design of fibrous PTFE reinforcements opens up new engineering opportunities for the future development of high-stability PEM fuel cells. [Display omitted] • Cross-aligned PTFE (CA-PTFE) framework is synthesized via electric-field guided electrospinning and subsequent calcination. • As a reinforcement, micron-scale patterned CA-PTFE framework is beneficial for the PFSA impregnation and the proton conduction. • CA-PTFE reinforced composite membrane shows the outstanding current density and exceptional durability in PEM fuel cells. [ABSTRACT FROM AUTHOR]

The therapeutic efficacy of intranasal iNOS siRNA delivery was investigated in the postischemic rat brain after encapsulating on in gelatin nanoparticles (GNPs; diameter 188.0 ± 60.9 nm) cross-linked with 0.0667% glutaraldehyde (GA). Intranasally delivered GNPs were found in extracellular and intracellular compartments of many brain regions, including the olfactory bulb, cerebral cortex, and striatum at 1 hour after infusion and continued to be detected for days. Infarct volumes were markedly suppressed (maximal reduction to 42.1 ± 2.6%) at 2 days after 60 minutes of middle cerebral artery occlusion (MCAO) when iNOS siRNA/GNPs were delivered at 6 hours post-MCAO. In addition, this protective effect was manifested by reductions in neurological and behavioral deficits that were sustained for 2 weeks. Therapeutic potency of iNOS siRNA/GNPs was significantly greater and sustained longer than that of bare siRNA and prolonged and efficient iNOS by iNOS siRNA/GNP is responsible for the robust neuroprotective effect. [ABSTRACT FROM AUTHOR]

Formation of stable solid electrolyte interphase (SEI) layer is critical to outstanding performance of energy storage devices, because it acts as a passive layer that allows facile transport of ions but forbids electron transport between the electrolyte and electrode. Although much study has been devoted to investigate the morphology and structure of SEI layer using a myriad of analytical devices on past decades, the direct observation of SEI layer on a real time scale has remained as a formidable challenge. In addition, it has been difficult to observe both the decomposition of electrolytes and formation process of stable SEI layer at nanometer scale. Here we utilize in situ transmission electron microscopy (TEM) using graphene liquid cell (GLC) to realize the observation of stable SEI layer formation in a sequential time scale. Upon e − beam irradiation, Li salts in the electrolytes react with reduced electrolytes and form gel-like agglomerates, which are deposited on the surface of the active material as a passivation layer and later stabilized to become more uniform in overall thickness. Additionally, growth dynamics of stable SEI layer were suggested, where the deposition of decomposed electrolytes eventually result in relatively uniform SEI layer. This paper demonstrates that it is possible to observe not only the formation of non-crystalline SEI layer but also the movement of decomposed electrolytes onto the surface of active materials which account for broader understanding of SEI layer, and has the potential to detect important interfacial phenomena in electrochemical devices that were overlooked so far. [ABSTRACT FROM AUTHOR]

High mobility group box 1 (HMGB1) is an endogenous danger signal molecule. In the postischemic brain, HMGB1 is massively released during acute damaging process and triggers inflammatory processes. Moreover, it has been reported HMGB1 augments the proinflammatory effect of LPS by direct interaction. In previous studies, the authors showed intranasally delivered a HMGB1 binding heptamer peptide (HBHP; HMSKPVQ) has robust neuroprotective effects in the ischemic brain after middle cerebral artery occlusion and that it exerts an anti-inflammatory effect. In the present study, the authors investigated whether HBHP suppresses the augmentation of the proinflammatory effect of LPS by HMGB1. In primary microglial cultures, low doses of LPS (5 ng/ml) and recombinant HMGB1 (rHMGB1, 20 ng/ml) synergistically activated microglial cells, and HMGB1–LPS binding was detected. In addition, synergistic NO accumulation along with direct HMGB1–LPS binding was also observed when primary microglial cultures were treated with LPS (5 ng/ml) and HMGB1 accumulated in NMDA-conditioned medium (NCM). Co-treatment of microglial cells with HBHP and LPS or rHMGB1 (NCM), or treatment with rHMGB1 or NCM and LPS after pre-incubating rHMGB1 (or NCM) with HBHP markedly suppressed their synergistic activation. Furthermore, interactions between rHMGB1 and LPS or between HMGB1 in NCM and LPS were suppressed dose-dependently by HBHP, indicating that HBHP suppressed the synergism between HMGB1 and LPS and the underlying mechanism involved inhibition of HMGB1–LPS binding. Together these results show HBHP has anti-inflammatory effects, and that it inhibits synergism caused by the binding of HMGB1 and LPS. [ABSTRACT FROM AUTHOR]

Hydro-electric technology has gathered much attention by the virtue of water as the energy source. However, the low energy density of this technology severely limits its practical use. Here, we demonstrate a PEDOT:PSS-based transpiration-driven electrokinetic power generator (p-TEPG) that enables the utilization of a wider variety of real-world water resources for maximizing energy generation efficiencies. In addition to the conventional electrical double layer on the material surface, the p-TEPG builds an additional potential difference in the polymer matrix by the selective penetration of cations into the matrix that contains sulfonate functional groups. p-TEPG exhibits 80–250% higher energy density than carbon-based TEPG at the same resistance. Moreover, seawater produced enhanced volumetric energy/power densities (34.36 mJ cm−3 and 44.70 μW cm−3) and areal energy/power densities (410 μJ cm−2 and 0.45 μW cm−2), respectively, compared to DI water on a single p-TEPG device, which is sufficient to charge electrical energy storage systems and directly operate low-powered electronic. • p-TEPG maximizes energy harvesting efficiency by ion-permselective PEDOT:PSS. • Green water resources improve performance of p-TEPG. • p-TEPG adsorbs more cations into its polymer matrix by sulfonate groups. • p-TEPG can increases energy harvesting efficiency by using anions and cations with smaller radii. • p-TEPG can be fueled with seawater, demonstrating its potential for blue energy generating system. [ABSTRACT FROM AUTHOR]

Flexible lithium–air batteries (F-LABs) operating under ambient air have attracted much interest as small-sized energy storage devices in routine household settings. Although the instability of the commonly used carbon cathode has prompted the search for a carbon-free cathode, there has not been much success in their development thus far. Here, we report a novel strategic approach to fabricate a large-area carbon-free cathode for shape-deformable F-LABs in ambient air. An electronically conductive and catalytic layer consisting of metallic iridium (Ir) and outermost IrO x was deposited on porous, flexible polyimide nanofibers (PI@IrO x NFs) by radio frequency (RF) sputtering, which was employed as the flexible cathode. Their properties were evaluated under dynamic deformation modes such as bending, folding, twisting, and crumpling. The F-LAB cells with PI@IrO x NFs were stable for 150 cycles using pure O 2 , and in a dry-air atmosphere (O 2 /CO 2 /N 2), they remain stable for 300 cycles (=600 h) with low discharge/charge overpotentials by the redox mediator and solid-state electrolyte (L 1.3 Al 0.3 Ti 1.7 (PO 4) 3 , LATP). We elucidate the reaction mechanism at the IrO x surface using ex-situ analyses and density functional theory (DFT) calculations. When applied to pouch-/cable-type F-LAB cells using two different electrolytes (gel-polymer and poly(ethylene oxide)(PEO)/LATP composite electrolytes), the PI@IrO x NFs show superior electrochemical characteristics during repetitive 300 bending cycles for over 60 h in ambient air. Furthermore, the F-LAB cells could be assembled using 3D-printed shape-deformable polyurethane (PU) as the packaging material, demonstrating their practical operation in small devices for the first time. [Display omitted] • Shape-deformable cathode for flexible Li-air batteries operating in ambient air is fabricated through a strategic approach. • Metallic iridium with the outermost IrO x phase is sputtered on mechanically stable, polyimide nanofibers. • The PI@IrO x NFs show excellent electrochemical performances using various electrolytes under dynamic deformation modes. [ABSTRACT FROM AUTHOR]

Wearable energy storage system must maintain robust electrochemical performance under severe mechanical and chemical deformations. Here, we demonstrate wearable supercapacitor system assembled with electrodes composed of one-step carbonized plant epidermis and gelatin based hydrogel electrolyte which possesses high electrochemical performance and superior reliability under ambient condition. The carbonized mulberry paper (MP) was used as an electrode to achieve improved volumetric energy density as well as mechanical-chemical reliability (e.g. mechanical toughness and acid resistance). Rationally designed active materials composed of vertically grown WO 3 NRs and reduced graphene oxide (rGO) anchored on MP, were employed for developing organism epidermis based supercapacitor. Such electrode exhibits high volumetric energy and power densities of 30.28 mWh cm−3 and 7.67 W cm−3, retaining the volumetric capacitance of 96.0% even after 110,000 charge-discharge cycles. As the final step, we employed the gelatin based electrolyte with high ionic conductivity to solve evaporation and leakage problems of conventional electrolytes. Organism epidermis based supercapacitor integrated with hydrogel electrolyte showed high electrochemical performance and long-term stability under ambient condition even after exposure to acid, demonstrating its gareat suitability as a large-scale wearable energy storage system. We demonstrate wearable supercapacitor system assembled with electrodes composed of one-step carbonized plant epidermis and gelatin based hydrogel electrolyte which possesses high electrochemical performance and superior reliability under ambient condition. Organism epidermis based supercapacitor integrated with hydrogel electrolyte showed high electrochemical performance and long-term stability under ambient condition even after exposure to acid, demonstrating its great suitability as a large-scale wearable energy storage system. [Display omitted] • We maximized areal and volumetric electrochemical performance (energy & power densities) and mechanical/chemical toughness through carbonized mulberry paper integrated with reduced graphene oxide (rGO) layer. Mulberry fibers inherently show excellent mechanical flexibility and acid resistance, since they have lower portion of lignin cellulose (~40%) compared with conventional paper fiber. However, electrochemically inactive mulberry fiber exhibits still low areal/volumetric energy densities and electrochemical reliability. Thus, we used carbonized mulberry paper as a substrate and electrode in this study, which was maximized for volumetric energy/power densities and mechanical/chemical toughness. • We have designed the plant-root inspired active materials structure with excellent electrochemical reliability and performances. Inspired from plant-root, we synthesized active materials structure by one-step reduction heat treatment, where WO 3 nanorods (NRs) vertically grow within the spaces of rGO and are anchored as strongly as plant-root on the carbonized mulberry fibers. The anchored structure can effectively maintain electrochemical performance and flexibility of carbonized paper by preventing delamination of WO 3 NRs even without protection layer. WO 3 NRs anchored carbonized mulberry paper (thickness 110 µm) with rGO layer exhibits volumetric capacitance retention of 96% for 110,000 cycles. In addition, maximum volumetric energy and power densities were increased to 30.28 mWh cm−3 and 7.67 W cm−3 (improvement of 220%). • Conventional liquid and gel-type electrolyte have critical issues including evaporation under ambient condition and leakage under mechanical bending-twisting deformation. Such problems are main causes of rapid electrochemical performance degradation. In our work, gelatin based hydrogel electrolyte extracted from porcine skin was integrated with electrode, in order to fabricate wearable energy storage system that is capable of operating in ambient conditions. The gelatin based hydrogel electrolyte can retain water contents and high ionic conductivity under ambient condition over 2 weeks. Ionic conductivity maintained 90.3% (228 mS cm−1) after two weeks of exposure to ambient condition, and the moisture content was maintained 98.0%. • We further extended organism epidermis based supercapacitor to large-scale application capable of operation in ambient condition. High hydrophilicity of mulberry paper enables the uniform deposition of precursor material for growth of WO 3 , i.e, WO 3 precursor, that is dispersed in the aqueous solution. As a result, GO and WO 3 precursor were uniformly deposited on large-area electrode with 9, 25, 49 cm2 followed by carbonization, resulting in the fabrication of large-scale organism epidermis based supercapacitor. [ABSTRACT FROM AUTHOR]

Water energy harvesters have received significant attention, due to wide distribution of water, simple device fabrication, and environmentally-friendly nature. Herein, we report a reliable water energy harvester by employing a composite that consists of synthesized micron-sized carbon as physical anchor, poly(styrene sulfonic acid) (PSSA) as proton supplier, and polyacrylic acid/carboxymethyl cellulose (PAA/CMC) as network binder. Single energy harvester fabricated using slurry casting at low temperature shows electrical output performance with output voltage of 0.4 V and current of 0.45 μA. Especially, the material combination enables both chemical and physical linkage and in turn, reliable electricity production was demonstrated, showing stable performance over 14 days without output degradation. Furthermore, the power level of energy harvesters was simply extended to drive commercial light emitting diodes (LEDs). Consequently, this approach introduced here is well-suited for developing a device with excellent electrical, structural, and chemical properties and the composite combination greatly broadens material choices that can be applied to develop sustainable water energy harvesters. Reliable water energy harvester was developed, thanks to rational composite choice (carbon as physical anchor and PSSA/PAA-CMC polymer network). Image 1 • Robust and high performance composite based water energy harvesters were developed through material combination using microsized carbon as physical anchor and cross-linked PSSA-PAA/CMC polymer as proton supplier. • Reliable DC output generation was demonstrated in ambient condition, lasting over 14 days without physical and chemical degradation. • Designed energy harvesters can be simply scaled-up to increase output power and in turn, commercial light-emitting-diode was driven by storing using capacitors up to 3 V. • A composite approach using simple, effective, and scalable route is introduced and this first attempt expands limited material choices to overcome single material's properties. [ABSTRACT FROM AUTHOR]

The astrocytic response to injury is characterized on the cellular level, but our understanding of the molecular mechanisms controlling the cellular processes is incomplete. The astrocytic response to injury is similar to wound-healing responses in non-neural tissues that involve epithelial-to-mesenchymal transitions (EMTs) and upregulation in ZEB transcription factors. Here we show that injury-induced astrogliosis increases EMT-related genes expression, including Zeb2 , and long non-coding RNAs, including Zeb2os , which facilitates ZEB2 protein translation. In mouse models of either contusive spinal cord injury or transient ischemic stroke, the conditional knockout of Zeb2 in astrocytes attenuates astrogliosis, generates larger lesions, and delays the recovery of motor function. These findings reveal ZEB2 as an important regulator of the astrocytic response to injury and suggest that astrogliosis is an EMT-like process, which provides a conceptual connection for the molecular and cellular similarities between astrogliosis and wound-healing responses in non-neural tissue. • Zeb2 promotes astrogliosis and preservation of neurological function after injury • Naive astrocytes have Zeb2 mRNA, but protein expression is induced only after injury • Stroke and SCI also modify expression of several lncRNAs, including Zeb2os • Zeb2 's role and gene expression changes suggest astrogliosis is an EMT-like process Vivinetto et al. identify the EMT-related transcription factor ZEB2 as a regulator of the astrocytic response to injury. Mouse models of either stroke or SCI show that knockout of Zeb2 in astrocytes attenuates astrogliosis, increases lesion sizes, and delays recovery motor function. Altogether, the findings suggest that astrogliosis is an EMT-like process. [ABSTRACT FROM AUTHOR]

Silicon-coated molybdenum sulfide nanosheets were prepared in a thin-film shape (Si–MoS 2 TFs) through metal organic chemical vapor deposition (MOCVD) and radio frequency (RF) sputtering. By using MOCVD, the MoS 2 thin films composed of nanosheets were vertically grown on stainless steel substrates. To address the problem of polysulfide dissolution and shuttling effect of MoS 2 during discharge and charge reactions in thin-film Li-ion batteries, the entire surfaces of MoS 2 TFs were covered with silicon layers using RF sputtering. Compared with pristine MoS 2 TFs without protection, the Si–MoS 2 TFs showed excellent reversibility with a high capacity of ∼2000 mAh g−1 for 500 cycles in thin-film Li-ion batteries. Both materials – MoS 2 and Si – were synergistically taken into account to enhance the ability to store Li ions in the host structures and complement each other during repeated conversion and alloying reactions. The underlying reaction principle was elucidated, which provides insight into developing MoS 2 -based thin-film cathodes. [ABSTRACT FROM AUTHOR]

[Display omitted] Electrodeposition and electropolymerization have emerged as versatile tools for the fabrication of chemical and biosensors. The literature in this area, published since 2017, is the main focus of this review. Electropolymerization has played a particularly prominent role in sensor development since its discovery in 1980 by Diaz at IBM. The ability to entrain receptors such as antibodies, engineered virus particles, and metal chelating agents into a conductive polymer sensing element during electropolymerization has proven to be a powerful means of preparing chemiresistors for a variety of analyses. Electrodeposition has also been used to prepare nanostructured metal indicator microelectrodes, enabling of a new modality for transducing biosensors. Electrodeposited metal nanowires have formed the basis for rapid and sensitive sensors for hydrogen gas. Electrodeposition has also been exploited as a powerful means for amplifying weak biosensor signals, extending their dynamic range. Opportunities for the application of electrodeposition and electropolymerization for chemical and biological sensor fabrication and function are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] van der Waals heterostructures (vdWHs), consisting of more than one type of atomically thin 2D crystal layers are emerging platforms for interesting electrical, optical, and catalytic applications. High yield production of vdWHs with atomic scale precision is crucial prerequisite for practical utilization. Here we present a generalized approach of random solution phase, high yield heteroassembly of semiconducting vdWHs by exploiting inherent surface charge states of 2D materials as well as chemical affinity of specific ligand end-functionalities. Facile removal of noncovalent functionalized ligands via simple pH reversal enables clean interfaces within vdWHs, yielding outstanding optoelectrical and electrochemical properties driven by fluent interfacial charge transfer among the layered 2D structures. The generality of this procedure is demonstrated by the formation of a series of different vdWHs such as WSe 2 -MoS 2 , graphene–MoS 2 - and phospherene–WSe 2 heterostructures. Atomically thin WSe 2 –MoS 2 phototransistor displayed an exceptionally fast response time with high sensitivity. Graphene–MoS 2 overcomes the inherent charge transfer issue of MoS 2 for electrochemical catalyst. Phospherene–WSe 2 successfully addresses poor ambient stability of phospherene together with enhanced surface activity towards chemical sensing. [ABSTRACT FROM AUTHOR]

For the last two decades, nanostructured carbon materials have attracted significant attention, as they exhibit unusual physicochemical properties different from their bulk counterpart. Nevertheless, agglomeration and re-stacking of carbon nanostructures have always limited optimal performance, with larger loading amount. To solve this issue, porous and compressible carbon-based sponges have been researched, but most of the previously suggested carbon foams were either not very porous, synthesized at high temperature heat treatment, and/or not applicable for carbon nanoparticles. In this work, we have successfully fabricated ultra-porous (porosity about 98–99%), polyimide-carbon nanoparticle (PI–C) composites by combining Ketjen black nanoparticles with PI short fibers, by simple freeze-drying and subsequent heat treatments at low temperature (240 °C). Based on the analysis, it has been discovered that the fabricated PI-C sponges not only exhibit highly robust mechanical properties but also retain low thermal conductivity even in comparison with pristine PI sponges. This work provides a milestone in fabricating a number of C-electrospun polymeric sponges by freeze drying and subsequent heat treatments, which are expected to be utilized in various fields of research. Image 1 [ABSTRACT FROM AUTHOR]

• Novel all-carbon fiber-based NO 2 sensor was fabricated for reliable environmental monitoring. Both RGO fiber and CNT fiber were synthesized by wet-spinning process, which is facile and compatible with large-scale production. • Unique sensing architectures of 1D graphene fiber were achieved with nitrogen doping for NO 2 sensors. Highly conductive nitrogen-doped reduced graphene oxide (RGO) fiber was achieved with wrinkled surface morphology. • CNT fibers were firstly demonstrated as heating networks for reversible NO 2 reaction. The CNT fibers with high electrical conductivity and mechanical stability are suitable for heating element to control the operating temperature of sensor. All-carbon fiber-based chemiresistor is fabricated by assembling reduced graphene oxide (RGO) fiber and carbon nanotube (CNT) fiber as reversible NO 2 sensing layer and flexible heater, respectively. Both graphene oxide (GO) and CNT fibers were synthesized by wet-spinning technique facilitating lyotropic nematic liquid crystal (LC) property. Randomly entangled CNT fiber-based heater, which is embedded in one surface of colorless polyimide (cPI) film with thickness of ˜200 μm, exhibits high bending stability and heating property up to 100 °C. Single reduced graphene oxide (RGO) fiber obtained after heat treatment at 900 °C in H 2 /N 2 ambient was integrated on the CNT fiber-embedded cPI heater, thereby establishing a new type of all-carbon fiber sensing platform. As a result, accelerated NO 2 adsorption and desorption kinetics were achieved with RGO fiber at an elevated temperature. In particular, a 9.22-fold enhancement in desorption kinetic (k des = 8.85 × 10–3 s–1) was observed at 100 °C compared with the desorption kinetic (k des = 0.96 × 10–3 s–1) at 50 °C, which was attributed to the effective heating by CNT fiber networks. This work pioneered a research on the use of emerging carbonaceous fibers for potential application in wearable chemical detectors. [ABSTRACT FROM AUTHOR]

Abstract Formation cycle is a significant step in battery processing, as it leads to the build-up of stable solid electrolyte interphase layer that affects various parameters of batteries. Although fast formation cycle is more economical way to realize the battery production, it is generally known that fast formation cycle of conventional electrode materials leads to capacity degradation. In this study, we report the high-rate formation cycle step to induce excellent electrochemical performance, in the case of Co 3 O 4 nanoparticle. Surprisingly, Co 3 O 4 nanoparticle that runs in the formation cycle at rather high current density (1.0 A g−1) exhibits superior electrochemical performance compared with Co 3 O 4 nanoparticle that runs in the formation cycle at 0.05 A g−1. Such enhanced electrochemical performance after the high-rate formation cycle for Co 3 O 4 can be mainly attributed to the stabilization of solid electrolyte interphase layer upon cycling and initial partial agglomeration that forms secondary particles. This work firstly paves the possibility of employing high-rate formation cycle to induce improved electrochemical performance, which can also be extended to various alternative electrode materials. Graphical abstract Image 1 Highlights • Detailed in-depth study on the effect of high-rate formation cycle. • The effect of formation cycle was investigated for Co 3 O 4. • High-rate formation cycle leads to enhanced electrochemical performance. • Both interfacial and morphological transitions depend on formation cycle. [ABSTRACT FROM AUTHOR]

Semiconducting metal oxides (SMOs) based gas sensors are inherently hampered by requirement of high working temperature because of their wide bandgaps. Consequently, there are remain challenges to utilize SMOs based gas sensors with regard to continuous gas monitoring platform with low power consumption. To address the inherent limitation, nitridation (i.e., N doping) of WO 3 NFs to WO x N y NFs was herein introduced for realization of low-temperature NO 2 sensing. Importantly, nitridation was conducted at intervals of 50 °C from 400 to 600 °C to adjust the degree of phase transition from semiconducting WO 3 to conductive WON phases. To further optimize the conductivity and improve the sensing characteristics, i.e., reduction of optimal operating temperature and enhancement of sensitivity, WO x N y NFs were functionalized with platinum (Pt) catalytic nanoparticles (NPs) by physical mixing. Pt NPs functionalized WO x N y NFs nitrided at 550 °C exhibited improved normalized resistance change and superior selectivity against C 2 H 5 OH, C 7 H 8 , CH 4 , CO, NH 3 , and NO at 50 °C. The noble metal catalyst–metal oxynitride hybrid system is suggested as an effective NO 2 sensing platform for low-temperature chemical sensor. [ABSTRACT FROM AUTHOR]

Abstract LiNi 0.5 Mn 1.5 O 4 (LNMO) cathode thin films were prepared on Pt-coated stainless steel (SS) substrates by radio-frequency magnetron sputtering. The layers were post-annealed at 500, 600 and 700 °C to study the impact of thermal treatment on the crystallization of the cathode material. As the annealing temperature increases, interdiffusion occurs between the substrate and the LNMO film, which degrades the electrochemical properties of the cathode film. In order to mitigate this problem, an In-Sn-O (ITO) interlayer was introduced between Pt and the SS substrate. The ITO film is electrochemically stable and acts as an effective diffusion barrier between the substrate and the LNMO layer, which results in improved electrochemical properties of the LNMO film for a lithium ion battery. [ABSTRACT FROM AUTHOR]

Abstract Increasing the specific capacity and cycle life of graphitic carbon anodes is crucial for realizing high-performance lithium ion batteries. Herein, we introduce a new class of graphitic carbon anodes comprising highly ordered three-dimensional nanostructures decorated with SnO 2 nanoparticles. The inch-scale, nanostructured graphitic carbon matrices are prepared by supported pyrolysis of epoxy templates patterned by advanced optical lithography. During the subsequent decoration process, the SnO 2 nanoparticles are densely formed on the matrix without agglomeration since the periodic nanostructured matrix provides a homogeneous site for nucleation and growth. The surface coverage of the decorated SnO 2 nanoparticles and the mass relative to the graphitic carbon are >80% and ∼50 wt%, respectively. The resulting nanostructured C/SnO 2 composite monoliths can be assembled solely into LIB coin cells without the aid of binders and conducting agents. The achieved specific capacity and retention are 692 mAh g−1 and 87.31% (at 70th cycle), respectively, which is superior to those of nanostructured carbon anodes prepared in a similar way. [ABSTRACT FROM AUTHOR]

In the recent times, pseudocapacitive electrode materials have received great attention due to their considerable capability in storing ions at relatively fast charging rates. Among various candidates, niobium (V) pentoxide (Nb 2 O 5 ) has gained much attraction for lithium-ion batteries (LIBs) due to its insertion/extraction reaction with Li, safe redox potential, and considerably good capacity (about 200 mAhg −1 ). Nevertheless, low conductivity of Nb 2 O 5 has so far prevented its use as a viable electrode material for LIBs. In this study, we have successfully coated silver (Ag) nanoparticles (NPs) on the surface of one-dimensional orthorhombic Nb 2 O 5 fiber (1D T-Nb 2 O 5 ) using simple electrospinning processing. Ag NPs coated Nb 2 O 5 fibers (Ag-1D T-Nb 2 O 5 ) provided faster electron pathways, resulting in much improved capacity at a given current density with superior rate capabilities compared with pristine 1D T-Nb 2 O 5 . In addition, 1D T-Nb 2 O 5 was more suitable for coating Ag NPs compared with T-Nb 2 O 5 NPs, where its structural integrity was maintained even after cycling. As a result, effective coating of conductive Ag NPs on the 1D T-Nb 2 O 5 resulted in excellent cycle retention characteristics (179.7 mAhg −1 after 500 cycles at 500 mA g −1 ) as well as superior rate capabilities (103.6 mAhg −1 at a current density of 5000 mA g −1 ). [ABSTRACT FROM AUTHOR]

Structural and electronic modification of titanium oxide (TiO 2 ) nanomaterials induced by the co-introduction of fully disordered glass phase and oxygen vacancies can lead to remarkable advances in the electrode performance in emerging energy storage systems. We report on the effective co-creation of fully amorphous nanofibers (NFs) composed of black TiO 2-x and conductive carbons throughout the NF structure, and evaluate the materials as potential anodes in sodium-ion batteries. The black TiO 2-x nanofiber is successfully fabricated by electrospinning a precursor solution followed by a two-step sequential thermal treatment in an air and reducing atmosphere. The NF electrode could deliver approximately two-fold higher 2nd discharge capacity and an excellent kinetic performance even under high rates compared to that delivered by anatase-structured white TiO 2 NFs used as reference, because of (i) an inherent free volume in the glass phase corresponding to the enlarged Na + sites, (ii) increased electrical conductivity (low bandgap) resulting from the presence of Ti 3+ , (iii) introduction of conductive carbon agents around the TiO 2-x domain, and (iv) one-dimensional NF feature allowing numerous Na + reaction sites at the electrochemical interface. We also elucidate the morphological and structural changes in the nanofibers after discharge and charge by ex-situ characterizations. [ABSTRACT FROM AUTHOR]

Careful modulation of surficial and interfacial properties of electrode materials is a critical factor for determining overall electrochemical characteristics. Recent studies have indicated that metal oxide nanocoating layer (such as titanium (IV) oxide (TiO 2 )) on metal oxide anodes (such as tin (IV) oxide (SnO 2 )) exhibited superior electrochemical properties, but fundamental research on the effect and role of TiO 2 layer thickness has been limited. Here we have successfully conducted in-depth study on how the thickness of TiO 2 overlayer on SnO 2 can have significant influence in the overall parameters of electrochemistry. It is revealed that TiO 2 overlayer with 12 nm shows good cycle retention (75.8%) even after 80 cycles and retains capacity of 438.3 mAh g −1 even at high current density (5000 mA g −1 ). Surprisingly, it was further discovered that TiO 2 layer not only alleviates the volume expansion but also helps to facilitate Li ion transport compared with SnO 2 . The improvements in both ionic and electrical conductivity of TiO 2 layer are main factors in better cycle retention and rate capabilities. Finally, in situ transmission electron microscopy analysis was adopted to observe the growth dynamics of solid electrolyte interphase layer on TiO 2 @SnO 2 , which demonstrates that TiO 2 overlayer results in homogeneous and thinner interphase layer compared with SnO 2 NTs. [ABSTRACT FROM AUTHOR]