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Gel-polymer electrolyte (GPE) is a pragmatic choice for high-safety sodium batteries but still plagued by interfacial compatibility with both cathode and anode simultaneously. Here, salt-in-polymer fibers with NaF salt inlaid in polylactide (PLA) fiber network was fabricated via electrospinning and subsequent in situ forming gel-polymer electrolyte in liquid electrolytes. The obtained PLA-NaF GPE achieves a high ion conductivity (2.50×10-3â S cm-1) and large Na+ transference number (0.75) at ambient temperature. Notably, the dissolution of NaF salt occupies solvents leading to concentrated-electrolyte environment, which facilitates aggregates with increased anionic coordination (anion/Na+ >1). Aggregates with higher HOMO realize the preferential oxidation on the cathode so that inorganic-rich and stable CEI covers cathode' surface, preventing particles' breakage and showing good compatibility with different cathodes (Na3V2(PO4)3, Na2+2xFe2-x(SO4)3, Na0.72Ni0.32Mn0.68O2, NaTi2(PO4)3). While, passivated Na anode induced by the lower LUMO of aggregates, and the lower surface tension between Na anode and PLA-NaF GPE interface, leading to the dendrites-free Na anode. As a result, the assembled Na || Na3V2(PO4)3 cells display excellent electrochemical performance at all-climate conditions.
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Two novel stationary phases, 1-(4-bromobutyl)-3-methylimidazolium bromide bonded chitosan modified silica and 1-(4-bromobutyl)-3-methylimidazolium bromide bonded chitosan derivatized calix[4]arene modified silica stationary phase, were synthesized using 1-(4-bromobutyl)-3-methylimidazolium bromide bonding chitosan as a polarity regulator solving the limitation of the strong hydrophobicity of calixarene in the application of hydrophilic field. The resulting materials were characterized by solid-state nuclear magnetic resonance, Fourier-transform infrared spectra, scanning electron microscopy, elemental analysis, and thermogravimetric analysis. Based on the hydrophilicity endowed by 1-(4-bromobutyl)-3-methylimidazolium bromide bonded chitosan, the retention mode of ILC-Sil and ILCC4-Sil could be effectively switched from the hydrophilic mode to a hydrophilic/hydrophobic mixed mode and could simultaneously provide various interactions with solutes, including hydrophilic, π-π, ion-exchange, inclusion, hydrophobic, and electrostatic interactions. On the basis of these interactions, successful separation and higher shape selectivity were achieved among compounds that vary in polarity under both reverse-phase and hydrophilic interactive liquid chromatography conditions. Moreover, the ILCC4-Sil was successfully applied to the determination of morphine in actual samples using solid-phase extraction and mass spectrometry. The LOD and LOQ were 15 pg/mL and 54 pg/mL, respectively. This work presents an exceptionally flexible adjustment strategy for the retention and selectivity of a silica stationary phase by tuning the modification group.
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Solid-electrolyte interphase (SEI) seriously affects battery's cycling life, especially for high-capacity anode due to excessive electrolyte decomposition from particle fracture. Herein, we report an ultrathin SEI (3-4â nm) induced by Cu+ -tailored double electrical layer (EDL) to suppress electrolyte consumption and enhance cycling stability of CuS anode in sodium-ion batteries. Unique EDL with SO3 CF3 -Cu complex absorbing on CuS in NaSO3 CF3 /diglyme electrolyte is demonstrated by in situ surface-enhanced Raman, Cyro-TEM and theoretical calculation, in which SO3 CF3 -Cu could be reduced to CuF2 -rich SEI. Dispersed CuF2 and F-containing compound can provide good interfacial contact for formation of ultrathin and stable SEI film to minimize electrolyte consumption and reduce activation energy of Na+ transport. As a result, the modified CuS delivers high capacity of 402.8â mAh g-1 after 7000â cycles without capacity decay. The insights of SEI construction pave a way for high-stability electrode.
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Polymer electrolytes provide a visible pathway for the construction of high-safety quasi-solid-state batteries due to their high interface compatibility and processability. Nevertheless, sluggish ion transfer at room temperature seriously limits their applications. Herein, a triangular synergy strategy is proposed to accelerate Na-ion conduction via the cooperation of polymer-salt, ionic liquid, and electron-rich additive. Especially, PVDF-HFP and NaTFSI salt acted as the framework to stably accommodate all the ingredients. An ionic liquid (Emim+ -FSI- ) softened the polymer chains through a weakening molecule force and offered additional liquid pathways for ion transport. Physicochemical characterizations and theoretical calculations demonstrated that electron-rich Nerolin with π-cation interaction facilitated the dissociation of NaTFSI and effectively restrained the competitive migration of large cations from EmimFSI, thus lowering the energy barrier for ion transport. The strategy resulted in a thin F-rich interphase dominated by NaTFSI salt's decomposition, enabling rapid Na+ transmission across the interface. These combined effects resulted in a polymer electrolyte with high ionic conductivity (1.37×10-3 â S cm-1 ) and tNa+ (0.79) at 25 °C. The assembled cells delivered reliable rate capability and stability (200 cycles, 99.2 %, 0.5â C) with a good safety performance.
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In order to solve the problems of slow detection speed, large number of parameters and large computational volume of deep learning based gangue target detection method, we propose an improved algorithm for gangue target detection based on Yolov5s. First, the lightweight network EfficientVIT is used as the backbone network to increase the target detection speed. Second, C3_Faster replaces the C3 part in the HEAD module, which reduces the model complexity. once again, the 20 × 20 feature map branch in the Neck region is deleted, which reduces the model complexity; thirdly, the CIOU loss function is replaced by the Mpdiou loss function. The introduction of the SE attention mechanism makes the model pay more attention to critical features to improve detection performance. Experimental results show that the improved model size of the coal gang detection algorithm reduces the compression by 77.8%, the number of parameters by 78.3% the computational cost is reduced by 77.8% and the number of frames is reduced by 30.6%, which can be used as a reference for intelligent coal gangue classification.
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Development of high energy density lithium-metal batteries (LMBs) is markedly hindered by the interfacial instability on lithium-metal anode side. Solid-electrolyte interphase (SEI) is a fundamental factor to regulate dendrite growth and enhance the stability of lithium-metal anodes. Here, trithiocyanuric acid, a triazine derivative with sulfhydryl groups, is used as an efficient promoter to favor the construction of a robust artificial SEI layer on the lithium metal surface, which greatly benefits the stability and efficiency of LMBs. With the assistance of trithiocyanuric acid facilely introduced on the Li surface via a one-step solution route, a highly uniform artificial SEI layer rich in Li2S and Li3N is formed, which efficiently facilitates uniform lithium deposition and suppresses lithium dendrite growth. Remarkably, the Li|Li cell displays stable lithium plating/stripping cycling over 800 h at 0.5 mA cm-2, 1 mAh cm-2, and the Li|LFP cells exhibit prolonged lifespan over 700 cycles at 3 C and superior rate performance from 2 to 20 C. This work provides a facile design strategy for constructing a superb artificial SEI layer for high-performance LMBs.
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An improved algorithm based on Yolov8s is proposed to address the slower speed, higher number of parameters, and larger computational cost of deep learning in coal gangue target detection. A lightweight network, Fasternet, is used as the backbone to increase the speed of object detection and reduce the model complexity. By replacing Slimneck with the C2F part in the HEAD module, the aim is to reduce model complexity and improve detection accuracy. The detection accuracy is effectively improved by replacing the Detect layer with Detect-DyHead. The introduction of DIoU loss function instead of CIoU loss function and the combination of BAM block attention mechanism makes the model pay more attention to critical features, which further improves the detection performance. The results show that the improved model compresses the storage size of the model by 28%, reduces the number of parameters by 28.8%, reduces the computational effort by 34.8%, and improves the detection accuracy by 2.5% compared to the original model. The Yolov8s-change model provides a fast, real-time and efficient detection solution for gangue sorting. This provides a strong support for the intelligent sorting of coal gangue.
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Algoritmos , Aprendizaje Profundo , Humanos , Carbón Mineral , Redes Neurales de la ComputaciónRESUMEN
Non-aqueous sodium-ion batteries (SiBs) are a viable electrochemical energy storage system for grid storage. However, the practical development of SiBs is hindered mainly by the sluggish kinetics and interfacial instability of positive-electrode active materials, such as polyanion-type iron-based sulfates, at high voltage. Here, to circumvent these issues, we proposed the multiscale interface engineering of Na2.26Fe1.87(SO4)3, where bulk heterostructure and exposed crystal plane were tuned to improve the Na-ion storage performance. Physicochemical characterizations and theoretical calculations suggested that the heterostructure of Na6Fe(SO4)4 phase facilitated ionic kinetics by densifying Na-ion migration channels and lowering energy barriers. The (11-2) plane of Na2.26Fe1.87(SO4)3 promoted the adsorption of the electrolyte solution ClO4- anions and fluoroethylene carbonate molecules, which formed an inorganic-rich Na-ion conductive interphase at the positive electrode. When tested in combination with a presodiated FeS/carbon-based negative electrode in laboratory- scale single-layer pouch cell configuration, the Na2.26Fe1.87(SO4)3-based positive electrode enables an initial discharge capacity of about 83.9 mAh g-1, an average cell discharge voltage of 2.35 V and a specific capacity retention of around 97% after 40 cycles at 24 mA g-1 and 25 °C.
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Hierro , Sulfatos , Adsorción , ElectrodosRESUMEN
Creating electrocatalysts with high activity and stability to meet the needs of highly effective seawater splitting is of great importance to achieve the goal of hydrogen production from abundant seawater source, which however is still challenging owing to sluggish oxygen evolution reaction (OER) dynamics and the existed competitive chloride evolution reaction. Herein, high-entropy (NiFeCoV)S2 porous nanosheets are uniformly fabricated on Ni foam via a hydrothermal reaction process with a sequential sulfurization step for alkaline water/seawater electrolysis. The obtained rough and porous nanosheets provide large active surface area and exposed more active sites, which can facilitate mass transfer and are conducive to the improvement of the catalytic performance. Combined with the strong synergistic electron modulation effect of multi elements in (NiFeCoV)S2, the as-fabricated catalyst exhibits low OER overpotentials of 220 and 299 mV at 100 mA cm-2 in alkaline water and natural seawater, respectively. Besides, the catalyst can withstand a long-term durability test for more than 50 h without hypochlorite evolution, showing excellent corrosion resistance and OER selectivity. By employing the (NiFeCoV)S2 as the electrocatalyst for both anode and cathode to construct an overall water/seawater splitting electrolyzer, the required cell voltages are only 1.69 and 1.77 V to reach 100 mA cm-2 in alkaline water and natural seawater, respectively, showing a promising prospect towards the practical application for efficient water/seawater electrolysis.
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All-solid-state lithium-ion batteries (ASSLBs) are considered as the most promising next-generation energy storage devices. In this work, a low-cost foldable nano-Li2MnO3 integrated Poly (ethylene oxide) (PEO) based composite polymer solid electrolyte (CPSE) is prepared by simply solid-phase method. Density functional theory calculations indicate that the LMO could provide faster ion transfer channels for the migration of lithium ions between PEO chains and segments. As such, the CPSE obtained has a high ionic conductivity of 5.1 × 10-4 S cm-1 at 60 °C with a high lithium ions transference number of 0.5. The CPSE remains stable even at high temperature with no heat escaping. This could improve the safety performance of the batteries. As a result, the lithium metal battery assembled with CPSE works stably after over 200 cycles at a high rate of 0.5C, and its specific capacity is as high as 125 mAh g-1. Also, it is confirmed that this CPSE adapts to three cathode materials. The Li metal pouch battery assembled with the CPSE is foldable and has excellent mechanical properties. All these results indicate that the CPSE obtained has excellent electrochemical and outstanding safety performances, which can make it have broad commercial applications in ASSLBs.
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Highly conductive metal sulfides with high theoretical capacities and good conductivity have been considered as anode material alternatives for sodium-ion batteries (SIBs). Unfortunately, the unsatisfactory cycling stability and poor rate performance are usually resulted from the sluggish electrochemical kinetics and volumetric expansion in the charge/discharge process, which severely restricts their applications. Herein, trimetallic sulfides embedded into the carbon matrix with a microsphere shape (denoted as CoNiZnS/C) were successfully prepared by a facile solid sulfidation of tri-metal-organic frameworks. The nanorods-assembled microsphere structure with abundant phase boundaries of multiphase in the CoNiZnS/C would provide abundant active sites and defects for storing sodium ions and rich voids to alleviate the volumetric strains. As the anode material of SIBs, the optimum composite named as CoNiZnS/C-2 in this work demonstrated high initial Coulombic efficiency (96.52% at 0.1 A g-1), good cycling stability (maintaining 410.7 mA h g-1 at the 960th cycle at 2.0 A g-1) and excellent rate performance (477.0 mA h g-1 at 5.0 A g-1). Thus, such a multi-metal sulfide composite with special physical-chemical properties may offer a new insight to promote the electrochemical performance of sulfide-based anode materials for the SIBs.
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A representative closely packed conjugated polyrotaxane (CPR1) is synthesized by threading polyaniline (PAN) into ß-cyclodextrin (CD) macrocycles and utilized for the first time to construct an RRAM device that exhibits an outstanding resistive switching capability. The CPR1 RRAM device displays remarkable nonvolatile memory performance with an extremely high ON/OFF ratio of 108, the ultra-fast response of 29 ns, excellent reliability and reproducibility, and long-term stability (more than 1 year). The mechanism underlying this resistive switching behavior is understood according to the electric-field-induced proton doping of the PAN core by the CD sheath through hydrogen bonding interactions. More impressively, the favorable solubility and intrinsic flexibility of CPR1 allow for large-scale fabrication of flexible CPR1 RRAM device arrays by full-printing technology with endurance of 1000 bending cycles at the minimum bending radius of 3 mm, higher ON/OFF ratio of 108, and relatively lower operating voltage of 1.8 V. This work shows the potential of CPR materials in highly stable memory devices for next-generation flexible and wearable electronics.
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Sodium-ion batteries (SIBs), being an attractive candidate of lithium-ion batteries, have attracted widespread attention as a result of sufficient sodium resource with low price and their comparable suitability in the field of energy storage. However, one of the main challenges for their wide-scale application is to develop suitable anode materials with excellent electrochemical performance. Herein, a novel orderly layered VMoS2 (OL-VMS) anode material was synthesized through a facile hydrothermal self-assembly approach followed by a heating procedure. As the anode material of the SIBs, the unique structure of OL-VMS not only facilitated the rapid migration of sodium ions between the stacked layers but also provided a stable framework for the volume change in the process of intercalation/deintercalation. In addition, vanadium mediating in the framework caused more defects to produce abundant storage sites for Na+. As such, the obtained OL-VMS-based anode exhibited high reversible capacities of 602.9 mAh g-1 at 0.2 mA g-1 and 534 mAh g-1 even after 190-cycle operation at 2 A g-1. Furthermore, the OL-VMS-based anode delivered an outstanding specific capacity of 626.4 mAh g-1 after 100-cycle testing at 2 A g-1 in a voltage range from 0.01 to 3 V. In particular, even in the absence of conductive carbon, it still showed an excellent specific capacity of 260 mAh g-1 at 1 A g-1 after 130 cycles in a 0.3-3 V voltage range, which should contribute to the cost reduction and energy density increase.
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Solid-state electrolytes with high ionic conductivity, large electrochemical window, and excellent stability with lithium electrode are needed for high-energy solid-state lithium batteries. In this work, a novel polyethylene oxide (PEO)-Lithium bis(trifluoromethylsulphonyl)imide (LiTFSI)-nanocomposite-based polymer electrolyte was prepared by using nickel phosphate (VSB-5) nanorods as the filler. The ionic conductivity of the obtained PEO-LiTFSI-3%VSB-5 solid polymer electrolyte was found to be as high as 4.83 × 10-5 S·cm-1 at 30 °C and electrochemically stable up to about 4.13 V versus Li/Li+. The enhanced ionic conductivity was attributed to the reduced crystallinity of the PEO and the interaction between VSB and 5 and PEO-LiTFSI. In addition, the solid polymer electrolyte exhibited improved compatibility to the lithium metal anode with excellent suppression of lithium dendrites. The assembled LiFePO4/Li battery with the PEO-LiTFSI-3%VSB-5 solid polymer electrolyte showed better rate performance and higher cyclic stability than the PEO-LiTFSI electrolyte. It is demonstrated that this new solid polymer hybrid should be a promising electrolyte applied in solid state batteries with lithium metal electrode.
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Baicalein and baicalin are the major flavonoids found in Scutellariae Radix, an essential herb which has had a presence in traditional Chinese medicine (TCMs) for more than two thousands of years. Owing to their similar characteristics and physiochemical properties, sensitive, it is a great challenge to detect both of them simultaneously. In this work, a novel, facile and sensitive electrochemical method was proposed based on tantalum oxide (Ta2O5), niobium oxide (Nb2O5) particles and antiseptic chitosan modified carbon paste electrode (Ta2O5-Nb2O5@CTS-CPE). Scanning electron microscope (SEM), X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV) and electrochemical impedance spectrum (EIS) were used to characterize the properties and investigate the electrochemical response of the sensor. The electrochemical behaviors and redox mechanisms of two analytes were investigated at the target electrode. Under the optimum conditions, the highly sensitive and simultaneous determination of baicalein and baicalin was successfully achieved with a linear response range of 0.08-8.0µM for both of them. The obtained detection limits for baicalein and baicalin were of 0.05 and 0.03µM (S/N=3), respectively. Furthermore, the proposed sensor displayed high sensitivity, excellent stability and satisfactory results in Scutellariae Radix samples analysis and hydrolysis process analysis of baicalin in vivo.
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Medicamentos Herbarios Chinos/química , Flavanonas/análisis , Flavonoides/análisis , Niobio/química , Óxidos/química , Scutellaria baicalensis/química , Tantalio/química , Carbono/química , Quitosano/química , Técnicas Electroquímicas/métodos , ElectrodosRESUMEN
Chrysin and baicalein are the major flavonoids found in oroxylum indicum, an essential herb in traditional Chinese medicine (TCM). Owing to their similar characteristics and physiochemical property, it is a great challenge to detect both of them simultaneously. In this work, tantalum oxide (Ta2O5) particles and chitosan modified carbon paste electrode (Ta2O5-CTS-CPE) was prepared and characterized by scanning electron microscope (SEM), X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV) and electrochemical impedance spectrum(EIS). Under the optimum conditions, the prepared Ta2O5-CTS-CPE exhibited excellent electrocatalytic activity toward the oxidation of chrysin and baicalein, and it could serve as the sensor for highly sensitive and simultaneous determination both of them. The linear range is 0.08-4.0µM for both of them, and the detection limits were determined to be 0.03 and 0.05µM (S/N=3) for chrysin and baicalein, respectively. Furthermore, the proposed electrochemical sensor displayed high sensitivity, excellent stability and got satisfactory results in oroxylum indicum samples analysis.
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Carbono/química , Quitosano/química , Técnicas Electroquímicas/métodos , Electrodos , Flavanonas/análisis , Flavonoides/análisis , Óxidos/química , Tantalio/química , Límite de Detección , Oxidación-ReducciónRESUMEN
A simple and sensitive voltammetric sensor for Orange II was developed, based on a poly(sodium p-styrenesulfonate)-functionalized graphene-modified glassy carbon electrode. This voltammetric sensor showed strong accumulation ability and an excellent voltammetric response for Orange II. The electrochemical behavior of Orange II was systematically investigated in a pH 7.0 phosphate buffer solution. By linear sweep voltammetry, under optimum conditions, a good linear relationship was obtained between peak currents and Orange II concentrations in the wider range of 3 × 10(-8) to 5 × 10(-6) mol/L, with an LOD of 1 × 10(-8) mol/L. In addition, the proposed Orange II sensor was successfully applied to real food samples with satisfactory recovery.
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Compuestos Azo/análisis , Bencenosulfonatos/análisis , Técnicas Electroquímicas , Grafito/química , Electrodos , Fosfatos/químicaRESUMEN
The coordination features of an imidazole dicarboxylate ligand, 2-(3-methoxyphenyl)-1H-imidazole-4,5-dicarboxylic acid (m-H(3)MOPhIDC) has been explored. Consequently, seven coordination polymers, namely [Sr(m-HMOPhIDC)(H(2)O)](n) (1), [Sr(m-H(2)MOPhIDC)(2)](n) (2), [Cd(3)(m-H(2)MOPhIDC)(2)(m-HMOPhIDC)(2)(H(2)O)(2)](n) (3), [Cu(m-HMOPhIDC)(phen)](n) (phen = 1,10-phenanthroline) (4), [Cd(2)(m-HMOPhIDC)(2)(phen)(2)](n) (5) [Cd(2)(m-HMOPhIDC)(2)(2,2'-bipy)(2)](n) (2,2'-bipy = 2,2'-bipyridine) (6) and [Co(m-HMOPhIDC)(H(2)O)(2)](n) (7) have been hydro(solvo)thermally synthesized by fine control over synthetic conditions, and structurally characterized. X-ray single-crystal analyses reveal that these polymers indicate rich structural chemistry ranging from one-dimensional (4-7), two-dimensional (1 and 3) to three-dimensional (2) structures, and the m-H(3)MOPhIDC ligand in these polymers can be singly deprotonated or doubly deprotonated, and coordinates to metal ions by various modes. The thermal and fluorescence properties of the complexes 1-7 have been determined as well.