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The Rubik's cube PBA frameworks with infinite structural variations have been obtained by a simple coprecipitation method and exhibits enhanced cycling and rate performance when tested as the anode materials in alkali-ion batteries (LIBs, SIBs, and KIBs). More importantly, the storage mechanism of the Co-Zn PBA frameworks have also been explored by DFT, in-situ XRD, and XPS measurements. [Display omitted] • Successfully synthesized Rubik's Co-M PBAs and explored the storage mechanism of the anode in alkali-metal-ion batteries. PBA frameworks have stood out among metal–organic frameworks because of their easy preparation, excellent stability, porous structures, and rich redox properties. Unfortunately, their non-ideal conductivity and significant volume expansion during cycling prevent more widespread application in alkali-metal-ion (Li+, Na+, and K+) batteries. By changing the type and molar ratio of metal ions, Rubik's PBA frameworks with infinite structural variations were obtained in this study, just like the Rubik's cube undergoes infinite changes during the rotation. X-ray adsorption fine structure measurements have documented the existence and determined the coordination environment of the metal ions in the Rubik's PBA framework. Benefiting from the more stable Rubik's cube structures with diverse composition, enhanced conductivity, and greater adsorption capacity, the obtained Rubik's cubes CoM-PBA anodes, especially CoZn-PBA deliver the enhanced cycling and rate performance in all the alkali-metal-ion batteries. The findings are supported by density functional theory calculations. Ex-situ X-ray photoelectron spectroscopy, and in-situ X-ray diffraction measurements were undertaken to explore the storage mechanism of CoZn-PBA anodes. Our results further demonstrate that the Rubik's cube PBA framework-based materials could be widely applied in the field of alkali-metal-ion batteries. [ABSTRACT FROM AUTHOR]

Lithium sulfide was produced in a plasma system by the reaction of plasma-ionized sulfur with lithium metal. Thermodynamic calculations and optical emission spectroscopy were used to investigate the chemical behavior and reaction mechanism of lithium metal in sulfur plasma atmosphere. The effects of radiofrequency (RF) power and radiofrequency (RF) time on the properties of lithium sulfide prepared by the cold plasma method were investigated. The macroscopic morphology, microscopic morphology, elemental distribution and phase of the sulfide product (lithium sulfide) were further tested and analyzed. The results show that under the conditions of power ≥ 210 W and time ≥ 15 min, Li2S2-free lithium sulfide with high purity is generated; with the enhancement of power, lithium oxide is transformed into lithium sulfide. Subsequently, its electrochemical performance as a battery anode was tested. The test obtained: the specific capacity of charging is up to 216.9 mAh/g, and the specific capacity of discharging is up to 182.8 mAh/g; the impedance has a double capacitance to resist arcing, which can be carried out normally in the charging and discharging process, and it has a certain degree of electrochemical performance. [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]

One possible approach to improve the fast charging performance of lithium‐ion batteries (LIBs) is to create diffusion channels in the electrode coating. Laser ablation is an established method for creating such structures and improving the performance of conventional LIBs. However, this method has not yet been used in industrial battery production due to different reasons. The drawbacks of this method are thermal stress, loss of active material, and discontinuous process flow. Herein, a novel concept is presented that enables the structuring of electrodes by selectively introducing a secondary fluid into the wet coating of the electrode. This displaces the active material prior to drying, resulting in no loss of active material and maintaining mechanical integrity. This innovative process is being tested for graphite anodes on a lab scale. Initial results show that the process can create pores that are comparable to laser‐structured electrodes. There is no visible damage to the electrode and no decrease in mechanical strength due to the structuring is observed. By varying the process parameters, different pore geometries can be generated with continuous process control, which are visually measured in this work. There is also a noticeable increase in performance when fast‐charging these electrode anodes. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks are recognized as active electrode materials for rechargeable batteries due to their structural diversity, abundant electrochemical active sites and large ion diffusion channels. Herein, nickel-terephthalic acid metal-organic frameworks (Ni-PTA MOFs) with different crystal and morphology structures are synthesized via a facile solvothermal method by simply adjusting the nature of solvent. Due to the fewest guest molecules and porous structure, the Ni-PTA resulting from the combinations of DMF and EtOH exhibits the comparatively higher chemical/thermal stability and shortened ion diffusion pathway. As a result, it exhibits a high discharge/charge capacity of 2196.4 and 1762.3 mAh g−1 at the first cycle and retains 1300 mAh g−1 after 50 cycles at 100 mA g−1 when tested as anode materials for Li-ion batteries. Even when the current density reaches 4000 mA g−1, it maintains a capacity of 452 mAh g−1. This work provides possibilities for regulating the crystal and morphology structure of MOFs as high performance anode materials for lithium ion batteries. [ABSTRACT FROM AUTHOR]

The electrode is a key component in a microbial electrolysis cell (MEC) that needs significant improvement for practical implementation. Accurate and reproducible analytical methods are substantial for the effective development of electrode technology. Linear sweep voltammetry (LSV) is an essential analytical method for evaluating electrode performance. In this study, inoculated carbon brush (IB), abiotic brush (AB), Pt wire (PtW), stainless steel wire (SSW), and mesh (SSM) were tested to find the most suitable counter electrode under different medium conditions. The coefficient of variation (Cv) of maximum current (Imax) was the most decisive indicator of the reproducibility test. This study shows that (i) the electrode used in operation is an appropriate counter electrode in an acetate-added condition, (ii) the anode LSV test should avoid the use of Pt wire as counter electrodes, and (iii) PtW is an appropriate counter electrode in cathode LSV in all conditions. [ABSTRACT FROM AUTHOR]

Implantable and wearable bioelectronic systems can enable tailored therapies for the effective management of long-term diseases, thus minimising the risk of associated complications. In this context, glucose fuel cells hold great promise as in- or on-body energy harvesters for ultra-low-power bioelectronics and as self-powered glucose sensors. We report here the generation of gold nanostructures through a gold electrodeposition method in a soft template for the abiotic electrocatalysis of glucose in glucose fuel cells. Two different types of soft template were used: a lipid cubic phase-based soft template composed of Phytantriol and Brij®-56, and an emulsion-based soft template composed of hexane and sodium dodecyl sulphate (SDS). The resulting gold structures were first characterised by SAXS, SEM and TEM to elucidate their structure, and then their electrocatalytic activity towards glucose was compared in both a three-electrode set-up and in a fuel cell set-up. The Phytantriol/Brij®-56 template led to a nanofeather-like Au structure, while the hexane/SDS template led to a nanocoral-like Au structure. These templated electrodes exhibited similar electrochemical active surface areas (0.446 cm2 with a roughness factor (RF) of 14.2 for Phytantriol/Brij®-56 templated nanostructures and 0.421 cm2 with an RF of 13.4 for hexane/SDS templated nanostructures), and a sensitivity towards glucose of over 7 μA mM−1 cm−2. When tested as the anode of an abiotic glucose fuel cell (in a phosphate-buffered solution with a glucose concentration of 6 mM), a maximum power density of 7 μW cm−2 was reached; however the current density in the case of the fuel cell with the Phytantriol/Brij®-56 templated anode was approximately two times higher, reaching the value of 70 μA cm−2. Overall, this study demonstrates two simple, cost-effective and efficient strategies to manipulate the morphology of gold nanostructures, and thus their catalytic property, paving the way for the successful manufacturing of functional abiotic glucose fuel cells. [ABSTRACT FROM AUTHOR]

Fluoroethylene carbonate (FEC) and vinylene carbonate (VC) are considered the most effective electrolyte additives for improving the solid electrolyte interphase (SEI) of Si‐containing anodes while lithium difluorophosphate (LiDFP) is known to improve the interphases of cathode materials and graphite. Here, we combine VC, FEC, and different amounts of LiDFP in a highly‐concentrated electrolyte to investigate the effect on Si‐dominant anodes in detail. Cycle life tests, electrochemical impedance spectroscopy and rate tests with anode potential monitoring were conducted in Si/NCM pouch cells. The results reveal that adding LiDFP to the electrolyte improves all performance criteria of the full cells, with a concentration of 1 wt% being the optimal value for most cases. Post‐mortem analyses using scanning electron microscopy and x‐ray photoelectron spectroscopy showed that a more beneficial SEI film was formed for higher LiDFP concentrations, which led to less decomposition of electrolyte components and a better‐maintained anode microstructure. [ABSTRACT FROM AUTHOR]

Flexible anodes are a common form of anode ground bed for the cathodic protection of buried pipes in station areas, especially in new stations. In most cases, flexible anode ground beds could obtain uniform potential distribution and good protection. However, in the process of operation, there are also failure conditions such as anode body or cable breakage, electronic shorting between anode and pipes and other situations, resulting in poor protection. How to troubleshoot failures has become a difficult problem restricting the application of flexible anodes in actual production. In this paper, the failures of a flexible anode cathodic protection system in a station were assessed and analyzed in detail. The main reasons for the failures were the electronic shorting between the flexible anode and buried pipe in local area and the breaking of a partial flexible anode. The troubleshooting methods for two kinds of failures were explored. By measuring the potentials of both the flexible anode and pipes in different areas and the excavation test, the location of electronic shoring was determined. And through measuring the grounding resistance of the flexible anode and excavation test, the breaking location of the flexible anode was found. By repairing the failure sites, the failed system was restored to normal, which could provide guidance for the failure analyses of the flexible anode cathodic protection system. [ABSTRACT FROM AUTHOR]

Excessive mechanical loading of lithium-ion batteries can impair performance and safety. Their ability to resist loads depends upon the properties of the materials they are made from and how they are constructed and loaded. Here, prismatic lithium-ion battery cell components were mechanically and optically characterized to examine details of material morphology, construction, and mechanical loading response. Tensile tests were conducted on the cell case enclosure, anodes, cathodes, and separators. Compression tests on stacks of anodes, cathodes, separators, and jellyrolls were made from them. Substantially differing behaviors were observed amongst all components tested. An optical examination of the anodes, cathodes, and separators revealed homogeneities, anisotropies, and defects. Substantial texturing was present parallel to the winding direction. When highly compressed, jellyrolls develop well-defined V-shaped cracks aligned parallel to the texturing. Like many laminates, altering the lay-up construction affects jellyroll mechanical performance. To demonstrate, a cross-ply jellyroll was fabricated by rotating every other complete component set (cathode/separator/anode/separator), reassembling, and compressing. A distinctly different fracture pattern and increased compressive strength were observed. [ABSTRACT FROM AUTHOR]

Pesticides are used worldwide in agriculture to prevent insects and other pests that attack plants and their derivatives. Acetamiprid (ACT) is a type of insecticide belonging to the chemical group of neonicotinoids, which are widely used in agricultural planting to replace organophosphates. Therefore, in this work, the performance of the electrochemical oxidation (EO) process as an alternative solution to eliminate pesticides in water was evaluated. A dimensionally stable anode (DSA, TiO2-RuO2-IrO2) and boron-doped diamond (BDD) were tested as anodes for degrading ACT (30 and 300 mg L−1) by using different applied current densities (j): 30, 60, 90, and 120 mA cm−2. The degradation process was monitored by using ACT decay, spectrophotometric analysis, and chemical oxygen demand. The results clearly showed that ACT (30 mg L−1) was only eliminated from water at the DSA electrode when 90 mA cm−2 was applied, reaching higher removal efficiencies after 180 min of electrolysis. Conversely, ACT was quickly removed at all applied current densities used, at the same concentration. On the other hand, when the ACT concentration was increased (300 mg L−1), 71.4% of the COD removal was reached by applying 90 mA cm−2 using BDD, while no significant improvements were achieved at the DSA electrode when a higher concentration of ACT was electrochemically treated. [ABSTRACT FROM AUTHOR]

Co‐insertion of protons happens widely and enables divalent‐ion aqueous batteries to achieve high performances. However, detailed investigations and comprehensive understandings of proton co‐insertion are scarce. Herein, we demonstrate that proton co‐insertion into tunnel materials is determined jointly by interface derivation and inner diffusion: at the interface, hdrated Mg2+ has poor insertion kinetics, and therefore accumulates and hydrolyzes to produce protons; in the tunnels, co‐inserted/lattice H2O molecules block the Mg2+ diffusion while facilitate the proton diffusion. When monoclinic vanadium dioxide (VO2(B)) anode is tested in Mg(CH3COO)2 aqueous solution, the formation of Mg‐rich solid electrolyte interphase on the VO2(B) electrode and co‐insertion of derived protons are probed; in the tunnels, the diffusion energy barrier of Mg2++H2O is 2.7 eV, while that of the protons is 0.37 eV. Thus, protons dominate the subsequent insertion and inner diffusion. As a consequence, the VO2(B) achieves a high capacity of 257.0 mAh g−1 at 1 A g−1, a high rate retention of 59.1 % from 1 to 8 A g−1, and stable cyclability of 3000 times with a capacity retention of 81.5 %. This work provides an in‐depth understanding of the proton co‐insertion and may promote the development of rechargeable aqueous batteries. [ABSTRACT FROM AUTHOR]

A solution to improve the energy efficiency of aluminum smelting by preheating prebaked anodes is proposed. The reduction of electricity consumption is calculated, and the advantages of the prebaked anode preheating technology are assessed. Pilot tests of the anode preheating technology were prepared and conducted. The results of mathematical modeling and practical tests of the technology are presented. After the replacement of the anode blocks, the currents in the anode holders of the pilot anode and in the witness anodes were measured. The theoretical energy savings for two hundred 300–350 kA electrolytic cells exceed 6 mln kW·h of electricity per year in the absence of significant capital expenditures. The adoption of the technology requires an insignificant change in the operational expenditures due to changes in the logistics of storage and delivery of anodes for replacement. [ABSTRACT FROM AUTHOR]

Owing to the rich redox functionalities and numerous pore structure, metal‐organic frameworks (MOFs) are directly emerging as prospective electrode materials with special properties. In the present study, exotic and unique nanomaterials of copper‐based metal‐organic framework (Cu‐MOF‐74) were successfully prepared by coordination assembly of Cu (II) and 2,5‐dihydroxyterephthalic acid (DHTA) through the solvothermal route and served as anode materials for lithium‐ion batteries for the first time. The Cu MOF has a coral cluster‐like nanoporous morphology composed of hexagonal columns with a length of 3.0 μm and a radius of 132 nm. When tested as anode, it achieved a high reversible capability of 870.3 mA h g−1 at 100 mA g−1, remarkable rate performance (up to 1000 mA h g−1) and a long service life (300 cycles) in the dis‐/charge process. Such outstanding properties of the MOF anode may be mainly ascribed to the conjugated ligand moiety and the particular microstructural features. The results of this study provided insights for the rational design of primitive MOFs for advanced lithium storage. [ABSTRACT FROM AUTHOR]

BACKGROUND: The anode material of bioelectrochemical systems (BES) is crucial because its characteristics directly affect electron transfer from the bacteria to the anode. To assess its usefulness, each material must undergo evaluation under relevant operating conditions, as well as a complete electrochemical characterization. RESULTS: Five carbonaceous materials – carbon brush (CB), carbon granules (CG), thicker carbon felt (CF1), high‐conductivity carbon felt (CF2), and high‐active‐area carbon felt (CF3) – anodes were tested in this work. The current generation with each anode material was studied, operating as a microbial fuel cell (MFC) and microbial electrolysis cell (MEC). Two MFC inoculation strategies were tested: (i) fixed 10 Ω external resistance (ER) and (ii) poised anode potential (PA) of 200 mV versus Ag/AgCl. Once reproducible cycles were obtained in MFC operation, CB yielded the highest maximum current density, amounting to 15.9 A m−2. A slightly reduced start‐up time was observed for each anode with PA than ER. When the anodes were transferred to MEC operation, the maximum hydrogen production rate of 1.04 m3 H2 m−3 d−1 was obtained for CB. CONCLUSION: This study helps in selecting anode material for BES, allowing a shortening of the start‐up time and improving its performance using different inoculation strategies and anode materials. Among all the anode materials employed in this study, CB and CF3 electrodes presented the best overall performance. © 2023 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Carbon from inexpensive biomass‐based precursors have shown promise as anode materials for application in sodium/lithium ion battery technology. However, their practical implementation is marred by unreliable cycling stability and unimpressive initial coulombic efficiency. The electrochemical properties of such biomass derived carbon can be improved considerably by material engineering via suitable heteroatom doping. In this work, the effect of phosphorous and fluorine doping on naseberry seed derived carbon has been explored. The doping led to an increase in the specific capacity and rate performance of the modified bio‐based carbon in comparison to non‐doped counterparts. The P/F incorporated carbon delivers reversible capacity of 812 mAh g−1 and 409 mAh g−1 at 0.1 A g−1 when tested as anode in lithium/sodium ion coin cell. The long term cycling of the material at a higher current rate of 1.0 A g−1 is also impressive. The reason for this enhanced electrochemical performance has been analysed through electrochemical impedance spectroscopy and post mortem electron microscopic studies. The increase in interlayer spacing, cell volume and ionic conductivity in the P/F incorporated carbon which leads to an improvement in the electrochemical properties has also been corroborated via DFT analysis. [ABSTRACT FROM AUTHOR]

Organic compounds have become a potentially important choice for a new generation of energy-storage electrode materials due to their designability, flexibility, green sustainability, and abundance. However, the applications of organic electrode materials are still limited because of their dissolution in electrolytes and low electrical conductivity, which in turn cause poor cycling stability. Here, for the first time, we report 2-amino-4-thiazole-acetic acid (ATA) and its sodium salt, sodium 2-amino-4-thiazol-derived polymer (PATANa), as an anode. The PATANa showed a two-dimensional (2D) nanosheet structure, offering a larger contact area with the electrolyte and a shorter ion-migration path, which improved the ion-diffusion kinetics. The polymer showed excellent cycling stability and outstanding rate capability when tested as an anode for sodium-ion batteries (SIBs). It could deliver a high reversible specific capacity of 303 mA h g−1 at 100 mA g−1 for 100 cycles and maintain a high discharge capacity of 190 mA h g−1 after 1000 long cycle numbers even at a high current density of 1000 mA g−1. This approach of salinizing the polymer opens a new way to develop anode materials for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Silicon-rich anodes are desired to leverage the energy capacity of lithium-ion batteries (LIBs) towards critical markets. We prepared new silicon-rich composite anodes with a nanofiber-in-microfiber architecture using a co-axial electrospinning setup. A polyvinyl alcohol (PVA) solution that allows high silicon content serves as the central stream, which holds silicon nanoparticles into short, branched composite nanofibers. These nanofibers were wrapped by long, ductile microfibers made of polyacrylonitrile (PAN) that is supplied in the sheath fluid. After carbonization, the received carbon/silicon composites were tested as the anode of LIBs, in which the silicon-rich nanofibers host the majority of lithium ions while their thin carbon skin originated from PVA promotes the conductivity and charge transfer. The outside PAN-derived microfibers provide needed structural support for those encapsulated silicon-rich nanofibers, making the final composites also an integrated, three-dimensional current collector. The nanofibrous morphology and the void space in between help accommodate the notorious volume expansion issues during lithiation/delithiation. The new composites were confirmed on their nanofiber-in-microfiber configuration. With a Si content of 40%, this unique fibrous anode material achieves ∼900 mAh g−1 specific capacity and ∼90% capacity retention from cycle 50 to cycle 250 by effectively balancing some major challenges associated with silicon-rich anodes. [Display omitted] [ABSTRACT FROM AUTHOR]

Cobalt-iron (CoFe) layered double hydroxides (LDHs) have received much interest for supercapacitors (SCs) because of their ion-insertable layer structure. However, there is still a need for more effort to increase their potential window and overall electrochemical energy storage capability as SC electrodes. In this work, we present a straightforward approach to synthesizing CoFe-LDHs on zinc oxide seeded carbon cloth (ZnO@CC) via a one-step hydrothermal reaction; the obtained electrode is denoted as CoFe-LDH@ZnO@CC. The electrochemical energy storage properties of CoFe-LDH@ZnO@CC are tested as an anode material using a three-electrode setup for SC applications in 1 M Na2SO4 electrolyte. It can operate in a wider potential window reaching up to 1.6 V, exceeding most previously reported anode materials. The CoFe-LDH@ZnO@CC displayed capacitive charge storage accounting for 76% of the total charge stored at 20 mV/s. The CoFe-LDH@ZnO@CC anode delivered a maximum capacitance of 299.8 F/g at 2 A/g, outstanding cycle stability, and retained 97.7% of the initial capacitance value for 5000 cycles at 16 A/g. This study introduces a new strategy for structurally designing electroactive materials for energy storage devices, which might be useful as an anode for SCs. [ABSTRACT FROM AUTHOR]

This study aims to systematically examine aging mechanisms of lithium-ion cells. For this purpose, three different commercially available cylindrical cells featuring nickel-rich cathodes and graphite-based anodes are tested. Each cell type undergoes five different aging methods, encompassing calendar aging, cyclic aging and a realistic drive cycle profile. Differential voltage analysis is employed as a non-destructive technique to gain insights into degradation modes of the aged cells. The findings suggest that in the cells equipped with nickel-cobalt-aluminum cathodes and graphite/silicon anodes, the primary aging mechanism involves growth of the solid electrolyte interface. Conversely, cells incorporating nickel-cobalt-manganese cathodes with a higher silicon content in the anode, experience a notable loss in anode capacity. The obtained results from electrochemical tests are validated through post mortem analysis including scanning electron microscopy, mercury porosimetry, computed tomography, and coin cell measurements. Through material characterisation analysis, differential voltage analysis proves to be a reliable, non-invasive method for aging investigation. [Display omitted] • Qualitative analyses of degradation modes in Li-ion cells through DVA. • Dependency of aging modes on the stage of aging for specific cell types. • Similar aging modes in accelerated and semi-real aging conditions. [ABSTRACT FROM AUTHOR]

In an ATON-type Hall effect thruster, a ring-shaped anode and a cusped magnetic field intersect the match between the anode shape and the field topology thus must be clarified to optimize the electron transport to the anode and consequently the design of a high-efficiency thruster. By changing the match pattern with both the change in the length of the anode ring and the axial displacement of the cusp magnetic field, this study experimentally investigated the influence of the match pattern on the discharge characteristics of an ATON-type thruster—P100—under the condition of a moderate discharge voltage. The experimental results show that there is a match pattern that always optimizes the performance of the P100 thruster. At the rated operation parameters (300 V of discharge voltage and 5 mg/s of propellant mass flow rate) and the rated magnetic field strength, the observed improvements on thrust (∼79 mN to ∼85 mN) and anode efficiency (∼46% to ∼55%) are significant. Through further theoretical analysis, this study revealed that the change in the characteristics of electron momentum and energy transfer in the near-anode region, induced by the change of the match pattern, is the basic reason. The findings of this work are instructive for both understanding the electron motion in a cusp magnetic field and guiding the design of the anode ring intersecting with a cusp magnetic field in an ATON-type Hall effect thruster. [ABSTRACT FROM AUTHOR]

The exfoliation of tridimensional crystal structures has recently been considered a new source of bidimensional materials. The new approach offers the possibility of dramatically enlarging the library of bidimensional materials, but the number of nanolayers produced so far is still limited. Here, we report for the first time the use of a new type of material, α-germanium nanolayers (2D α-Ge). The 2D α-Ge is obtained by exfoliating crystals of α-germanium in a simple one-step procedure assisted by wet ball-milling (gram-scale fabrication). The α-germanium nanolayers have been tested as anode material for high-performance LIBs. The results show excellent performance in semi-cell configuration with a high specific capacity of 1630 mAh g−1 for mass loading of 1 mg cm−2 at 0.1 C. The semi-cell was characterized by a constant current rate of 0.5 C during 400 cycles and different scan rates (0.1 C, 0.5 C, and 1 C). Interestingly, the structural characterization, including Raman spectroscopy, XRPD, and XPS, concludes that 2D α-Ge largely retains its crystallinity after continuous cycling. These results can be used to potentially apply these novel 2D germanium nanolayers to high-performance Li-ion batteries. [ABSTRACT FROM AUTHOR]

Cs4PbBr6 quantum dots are glass-based materials. The perovskite structural material of Cs4PbBr6 quantum dots has shown an unexpected electronic performance. However, the glass-based Cs4PbBr6 quantum dots' capacity becomes weaker when running in charge/discharge. Here, graphite was introduced to Cs4PbBr6 quantum dots using the grinding method to enhance the cycling stability of Cs4PbBr6 quantum dots. The 10%, 25%, 35%, 40%, 75% content Cs4PbBr6 quantum dots were added to graphite (CQDs/G) and CQDs/G as an active material for lithium anode in electronic testing. The test results displayed 35% Cs4PbBr6 quantum dots content in CQDs/G, showing an excellent cycle performance (136.5 mAh g−1 after 1000 cycles at 0.5 A g−1 current density) and good rate ability. Graphite protected the CQDs in the long term, and has high potential economic value. [ABSTRACT FROM AUTHOR]

[Display omitted] As a desirable candidate for lithium-ion batteries, potassium-ion batteries (PIBs) have aroused great interest because of their low cost and high power and energy densities. However, the insertion/extraction of K+ with a large radius (1.38 Å) usually bring about the destruction of the electrode materials. Here, ultrafine Fe 7 S 8 nanocrystals are successfully implanted into hollow carbon nanospheres (Fe 7 S 8 @HCSs) via a facile solvothermal method and subsequent novel low-temperature sulfurization, which avoid the aggregation of Fe 7 S 8 nanoparticles produced during high-temperature sulfidation. The ultrafine Fe 7 S 8 nanoparticles and hollow carbon spheres can not only buffer the severe expansion/shrinkage of electrode materials caused by the repeated insertion/extraction of K+, but also provide additional accessible pathways for the high-rate K+ transmission. When tested as an anode material for PIBs, Fe 7 S 8 @HCSs achieve impressive K+ storage capacity of 523.2 mAh g−1 at 0.1 A g−1 after 100 cycles and remarkable rate capacity of 176.3 mAh g−1 at 5 A g−1. Further, assembling this anode with a K 2 NiFe(CN) 6 cathode yields stable cycling performance, revealing its great potential for large-scale energy storage applications. [ABSTRACT FROM AUTHOR]

In this article, hierarchical hydrangea‐like MoS2/C composites are synthesized through a simple one‐pot solvothermal method followed by heat treatment for the first time. The morphology and electrochemical performance of MoS2/C are largely affected by the solvent composition and carbon content during the solvothermal process. The interlayer distance of few‐layer MoS2 is increased by the insertion of carbon layer for the unique hierarchical hydrangea‐like MoS2/C nanostructure. The cycling performance of MoS2/C is greatly improved because it takes advantage of both good conductivity and structural stability. When tested as an anode of a lithium‐ion battery, the results show that the reversible specific capacity of the MoS2/C electrode is 853.1 mAh g−1 after 80 cycles at a current density of 200 mA g−1 with capacity retention of 98.4%. Especially, when tested under 500 mA g−1, the reversible specific capacity can reach to 780.6 mAh g−1 after 200 cycles. [ABSTRACT FROM AUTHOR]

Extensive research has been conducted on aqueous Zn-MnO 2 batteries in the most common ZnSO 4 electrolyte. However, the present study focuses on Zn anode stability and subsequent pairing with the commonly utilized MnO 2 cathode in a low-concentration aqueous Zn (ClO 4) 2 electrolyte containing an organic additive, triethyl phosphate (TEP). The structural stability of Zn anodes in optimized additive-added and additive-free electrolytes is analyzed by assembling series of Zn∥Zn symmetry cells under various electrochemical conditions with varying depth of discharges between 20 and 60 %. As such, additive added electrolyte stabilizes the Zn anode over 250 h under high areal capacity/low areal current density of 38.3 mAh cm−2/11.3 mA cm−2 with 60 % depth of discharge at long half-cycle time of 29.5 h. The Zn-MnO 2 paired cells in the Zn (ClO 4) 2 electrolyte with and without additives registered reversible capacities of 262 and 247 mAh g−1, respectively, at 0.05 A g−1. These electrochemical features are completely different from those of the common ZnSO 4 electrolyte, whose electrochemical mechanism is still a subject of debate. [Display omitted] • Zn anodes tested in low concentration Zn(ClO 4) 2 electrolytes containing TEP additive. • Additive stabilizes Zn anodes at high DoDs-high areal capacities/current densities. • DoD 60 stabilizes half cycle high capacity of 38.3 mAh cm−2 for 29.5 h over 4 cycles. • With Zn-MnO 2 Zn-ion battery additive electrolyte provides ∼262 mAh g−1 at 0.05A g−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anode composed of polyelectrolyte complex membranes mixed with carbon black. • The polymeric anode was electroplated with Zn. • The platted anode was tested as a Zinc ion batterie. Conventionally, the anode of a primary Aqueous zinc-ion batteries (ZIBs) is metallic and rigid, which made it difficult to integrate into flexible designs. In this research, a composite polyelectrolyte complex (PEC) with cationic poly(diallyldimethylammonium chloride), anionic poly(sodium-4-styrenesulfonate) and carbon black (CB) as conductive filler (PEC-CB) was developed as an anode substrate for zinc deposition via electroplating technique. The Zinc-electroplated PEC-CB (Zn-PEC-CB) anode was characterized using electron microscopy and X-Ray diffraction analysis to verify the successful zinc coating. The Zn-PEC-CB was then assembled with PEC-CB-MnO cathodes in an ZIB setup. The results demonstrated the potential of PEC-based electrodes as a promising alternative to conventional materials in ZIBs, encouraging further exploration in energy storage applications. [ABSTRACT FROM AUTHOR]

Metal-organic framework (MOF-5) material was synthesized by solvothermal method. Porous carbon (C) and sulfur-doped porous carbon (S/C) were fabricated by calcining and vulcanization of MOF-5. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Raman spectroscopy were used to characterize the crystal structure and morphology of the samples. The electrochemical performance of C and S/C materials were tested as anode materials for lithium ion batteries (LIBs) and sodium ion batteries (SIBs). The S/C exhibits the high reversible capacity (1114.8 mAh g−1 after 100 cycles at 0.1 A g−1 and 485 mAh g−1 after 500 cycles at 2.0 A g−1), as anode for LIBs. It behaves a reversible discharge capacity of 268.8 mAh g−1 after 100 cycles at 0.1 A g−1 and a capacity of 157 mAh g−1 after 1000 cycles at 2.0 A g−1, as anode for SIBs. Compared with C, the electrochamical performance of S/C material is significantly improved. This is mainly because the bigger specific surface area and the doping of sulfur atoms increases the layer spacing and facilitates the kinetics of the intercalation and deintercalation of Li+ and Na+ ions, especially Na+ ions. • Sulfur-doped porous carbon (S/C) was fabricated by calcining and vulcanization of MOF-5. • The S/C exhibits a higher reversible capacity and better cycling stability than the C sample. • Sulfur doping can increase the layer spacing and facilitates the diffusion of Li+ and Na+ ions. [ABSTRACT FROM AUTHOR]

In present, new artemisinin‐based organic compounds (1–6) are designed and synthesized in excellent yields (up to 97 %) via Steglich Esterification reactions. All new artemisinin derivatives are tested as anode catalysts for hydrazine electrooxidation reactions with electrochemical methods in 1 M KOH/0.5 M N2H4 solution. Hybrid molecule 1 exhibits the best catalytic activity in hydrazine electrooxidation reaction with 2.28 mA cm−2 value. Moreover, response surface methodology (RSM) is applied to investigate of optimum electrode conditions. By using optimum conditions, hydrazine electrooxidation is obtained as 3.55324 mA cm−2. As a result, artemisinin‐based hybrid compounds may be alternative, and next‐generation anode catalyst for direct hydrazine fuel cells. [ABSTRACT FROM AUTHOR]

To further increase the energy density of rechargeable batteries to meet the rapidly growing needs of high‐energy consuming devices, various materials are tested as anode materials. Some of these newly developed anode materials exhibit anomalously high capacities that exceed their theoretical values. Advanced analytical techniques have revealed that unconventional reaction mechanisms account for these extra capacities. However, despite the potential to take current battery technology development to the next level, research on the utilization of these reactions is currently limited. Herein, a new strategy is proposed to maximize the reaction of ‐OH components by using crystal water to increase the extra capacity obtained from the abnormal reactions of LiOH species. In addition to the LiOH phase formed by the conversion reaction of metal hydroxides, the H2O inside Ni(OH)2 crystals contributes to the formation of LiOH, which then reacts with lithium. As a result, water‐containing Ni(OH)2 exhibits greater reversible capacities than bare Ni(OH)2 and NiO, thereby confirming the beneficial effects of crystal water. This novel concept for the enhancement of electrochemical ion storage capacities through the introduction of crystal water to conversion‐based anode materials can expand the design factors for maximizing the available capacities of active materials. [ABSTRACT FROM AUTHOR]

A simple, rapid, and low‐cost method for preparation of Co3O4 nanoparticles (Co3O4‐1 and Co3O4‐2) using solid‐state calcination of mixture of Co(NO3)2∙6H2O and salicylic acid (1:1 weight ratio) at two different temperatures of 500 and 600°C is reported. The morphologies and structure of the as‐prepared Co3O4 nanoparticles were characterized using X‐ray diffraction (XRD) and transmission electron microscope (TEM). In addition, we tested them as an anode material for lithium‐ion batteries. The cycling stability and electrochemical performance of the as‐prepared Co3O4 nanoparticles were excellent. A capacity of ≈1,100 mAh/g was obtained after 50 cycles at 100 mA/g and exhibited stable discharge behavior up to 50 cycles with high rate capability. [ABSTRACT FROM AUTHOR]

The effects of pore formers added into the extrusion slurry of anode support microtubes on the mechanical and electrochemical performance of the microtubes are investigated in this study. For this purpose, several microtubular anode supports are fabricated by using various pore formers with different particle sizes. The effect of pore former content is also taken into consideration for a certain pore former type. The flexural strengths of the anode support microtubes are measured via three point bending tests and reliability analysis is performed. The porosities of the anode supports are also determined along with microstructural investigations. The results reveal that the flexural strength decreases with increasing the particle size of the pore former employed for a fixed pore former content and with increasing the pore former content for a certain pore former material considered. In addition, a number microtubular cells are fabricated based on the various microtubular anode supports and their electrochemical performances are evaluated via performance and impedance tests. The impedance results indicate that the cell performance is mainly restricted by the diffusion polarization. Among the pore former materials considered in this study, the highest cell performance for a certain pore former content of 20 vol% is measured from the cell prepared with graphite (325 mesh) pore former at all temperatures and hydrogen flowrates studied. The optimization studies display that the cell performance can be further improved by increasing the pore former content to 22.5 vol% for this pore former material. • Effect of pore former for fabrication of anode support microtubes is investigated. • Microstructural and mechanical properties of the supports are determined. • Five-layered microtubular cells are built on different anode supports and tested. • The highest performance is obtained with graphite (325 mesh) at 25 vol% content. [ABSTRACT FROM AUTHOR]

Hollow cathodes are used as thermionic emitters in a variety of electric propulsion devices such as the Hall thruster. This work studies the derivation and discusses the results of a phenomenological (zero-dimensional) plasma model for a hollow cathode with open-end emitter and orificed keeper. This represents the first attempt to model the plasma in the three regions of hollow cathodes with open-end emitter geometry, i.e. the keeper orifice, the cathode–keeper gap, and the insert. The current continuity, ion balance, and plasma power balance equations are solved to compute the main plasma parameters in each of the aforementioned regions. One novelty of this work is the definition of mathematical fit functions for the dynamic viscosity and ionization and excitation rates for krypton. Moreover, the resistive losses in the cathode–anode region are estimated to model the cathode standalone diode testing with an external anode. The model delivers cathode operational parameters such as the discharge power and potential which are compared to experimental data for both xenon- and krypton-fed cathodes. Furthermore, the influence of the three regions' geometries and the propellant flow rate as well as the discharge current on plasma parameters and cathode power budget of sample cathodes is discussed at length. • Zero-dimensional plasma model allows for open-end emitter cathode power estimation. • Introducing mathematical fit functions for krypton-gas dynamic viscosity, ionization and excitation reaction rates, and electron–neutral scattering cross section. • Model prediction of experimental data from Xe- and Kr-fed open-end emitter cathodes. • Quantitative and qualitative model response to geometrical and operational control parameters. • Qualitative model response to heavy species temperature variation. [ABSTRACT FROM AUTHOR]

In this study, an electro-Fenton (EF) process using carbon felt (CF) as the cathode and titanium/platinum (Ti/Pt) as the anode was tested for removing rhodamine B (RhB) and other organic dyes in water. Characterization of the CF material was conducted by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The influence of various environmental factors (i.e. solution pH, current density, catalyst dosage, RhB concentration, and type of dyes and electrolytes) on the dye removal was investigated. The results show that the maximum removal efficiency of RhB was 98% within 15 min at the optimal conditions of 50 mgRhB/L, 0.05 M Na2SO4, pH 3, 0.1 mM Fe2+, and 6.67 mA/cm². The decomposition of RhB follows a pseudo-first-order model with the decomposition rate constant of 0.256 min-1. Radical quenching experiments show that superoxide plays a key role in RhB degradation. Finally, results show that CF has high stability and degradation efficiency, which is suitable as a cathode for the removal of organic dyes in wastewater. [ABSTRACT FROM AUTHOR]

Poly(2-chloroaniline-co-2-ethylaniline)-composite-Zn was synthesized by in situ chemical oxidative method using ammonium per sulphate as oxidant, HCl as dopant and linear alkyl benzene sulphonic acid (LABSA) as surfactant. The resulting copolymer composite was characterized by FTIR, and UV–Visible spectroscopic methods. The thermal stability was established using thermogravimetric analysis. The conduction mechanism was examined in terms of the dielectric constant and the electrical conductivity of 1.46 × 10–7 Scm−1 measured showed semiconducting nature. The oxidation/reduction potentials and electrochemical reaction of Li/copolymer cells were tested by cyclic voltammetric technique. Poly(2-chloroaniline-co-2-ethylaniline)-composite-Zn has been tested as anode in Li-ion batteries. The discharge and charge capacity of ~ 47 and ~ 14mAh/g at 1 to 5 cycles show good reversibility. This is a feasible value for using it as the positive electrode material in lithium ion secondary batteries. [ABSTRACT FROM AUTHOR]

La-doped titanate materials have been widely investigated as alternative Ni-free anodes for solid oxide fuel cells (SOFCs). In this study, La0.4Sr0.6TiO3 (LST) was synthesized using the solid-state reaction method and calcined in air. A three-electrode mode was applied to measure the electrochemical performance of LST-yttria-stabilized zirconia (YSZ) composite anode by testing its impedance spectra and the anode overpotential. The electrochemical behavior is strongly dependent on the sintering temperature and the YSZ content. The lowest polarization resistance of 0.26 Ω cm2 in 97% H2/3% H2O was obtained on the anode sintered at 1350 °C when adding 60 wt% YSZ. The cell with the LST–YSZ anode was operated at 10,000 ppm H2S-H2 at 850 °C for more than 10 h, and it exhibited excellent sulfur-tolerant ability. The LST–YSZ anode sintered in air instead of reducing condition is probably a potential anode material for SOFCs. The electrochemical performance of LST–YSZ anode depends strongly on the YSZ content and the calcination temperature tested by overpotential in a three-electrode mode. [ABSTRACT FROM AUTHOR]

In this paper, SiNPs/rGO nano-composites were prepared from porous silicon nanoparticles, synthesized from silica mineral (SiO2). Reduced graphene oxide (rGO) was synthesized by thermal reduction method. The Si NPs/rGO nano-composite synthesized by three methods using the (a) CTAB as surfactant (b) CTAB as surfactant and citric acid as a functional group and (c) without CTAB and citric acid and by only utilizing ultrasonic. The samples were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), UV–Vis, EDX and FTIR spectroscopy. The charge and discharge cycle performance test of anode electrode sample made in the first synthesis method (a), carried out by potential (Li/Li+) versus capacity measurement. The resulting anode showed an initial specific capacity of 1191 mAhg−1 and specific capacity of 845 mAhg−1 after 10 cycles at a current density of 100 mAg−1 and a coulombic efficiency of approximately 99.4% after these cycles. Porous nanoparticles have improved the electrochemical properties of the nano-composite along with the conductivity and buffering properties of rGO by creating a suitable space for lithiation/de lithiation process. [ABSTRACT FROM AUTHOR]

Recently, there has been a significant interest in the application of SnS 2 /MoS 2 2D nanostructure composites in lithium-ion batteries (LIBs) due to their advantageous conversion, intercalation, and alloying reactions, leading to high capacity during charge and discharge cycles. In this study, we successfully synthesized SnS 2 /MoS 2 composites with a 2D-nanoplate morphology using a single-step hydrothermal method. Specifically, the optimized SnS 2 /MoS 2 -3:1 composite was tested as anodes in coin cell LIBs, demonstrating an impressive capacity of 710 mAh/g at a current density of 500 mA/g, along with outstanding stability (800 cycles) and remarkable rate capability compared to other composites. The excellent electrochemical performance of the SnS 2 /MoS 2 -3:1 composite can be attributed to the moderately coupled SnS 2 and MoS 2 2D-nanosheets, which provide short lithium-ion transportation lengths, low charge transfer resistance, and dominant capacitive behavior. • Pioneering solvothermal method: Carbon-free SnS 2 -MoS 2 nanostructures crafted innovatively. • Simple, cost-effective synthesis: Economically viable strategy devised. • Remarkable electrochemical prowess:SnS 2 /MoS 2 -3:1 composite excels in coin cell lithium-ion batteries. • Impressive performance metrics: Gravimetric capacity of 710 mAh/g at 500 mA/g, enduring stability through 800 cycles. • Enhanced conductivity, reliable synthesis: Suitable for large-scale production, validated by conclusive results. [ABSTRACT FROM AUTHOR]

The application of carbonaceous materials other than graphite as an anode for lithium-ion batteries can generate significant advantages, mainly in terms of cost and sustainability while achieving high specific capacities. In this work, we successfully managed to tune the morphology of activated carbon prepared from argan shells to be used as an electrode material for lithium-ion batteries. Both Nanosphere-AC and Honeycomb-AC are obtained from the same precursor. The AC samples were comprehensively characterized using sorption isotherms, scanning electron microscopy, X-ray diffraction and Fourier-transforming infrared spectroscopy. Both materials were tested as anodes for lithium-ion batteries. It was found that Nanosphere-AC permitted great specific capacity (700 mAh.g−1at 50 mAh.g−1) and long-term cycling, showing no apparent capacity fade even after 200 cycles, offering promising application potential. Whereas Honeycomb-AC only achieved 220 mAh.g−1 at 50 mAh.g−1, but still exhibited great long-term cycling performance after 200 cycles and rate capability properties. [Display omitted] • Argan Shells were carbonized and activated using H 3 PO 4 or H 2 SO 4. • Morphological tunning can be achieved by optimizing the activation process. • Nanospere-AC (H 3 PO 4) and Honeycomb-AC (H 2 SO 4) had different textural properties. • Nanosphere-AC reached a superior specific capacity of 700 mAh.g−1 at 50 mA.g−1. • Nanosphere-AC shows no apparent capacity fade even after 200 cycles. [ABSTRACT FROM AUTHOR]

It is imperative to develop new electrode materials for aqueous multivalent metal ion batteries with electrochemistry abilities at extreme-low temperatures due to the possible extreme-cold operating conditions of batteries in the present or the future. Herein, as a proof-of-concept experiment, a new orthorhombic molybdenum-tungsten oxide (Mo 3 WO x) is synthesized by a wet-chemical method and tested as anode material for aqueous zinc ion batteries at extreme-cold temperatures (−40, −60 and −75 °C) for the first time. Two anti-freezing electrolytes are selected to examine the related half-cell performances, and 7.5 m ZnCl 2 aqueous solution is more suitable for Mo 3 WO x half-cells than 2 m Zn(BF 4) 2 aqueous solution. At −40 °C, Mo 3 WO x exhibits reversible charge capacity of 104.1 mAh g−1 at 100 mA g−1 and the charge capacity can still maintain 82.3 mAh g−1 after 100 cycles; and under further test at 5000 mA g−1, Mo 3 WO x shows a high initial charge capacity of 42.5 mAh g−1 together with a capacity retention ratio of 81.6 % after 10,000 cycles. It is worth highlighting that the high capacities of Mo 3 WO x delivered at −40 °C are even comparable with the capacities of some "new-type" anode materials for aqueous zinc ion batteries exhibited at ambient temperature. At colder temperatures of −60 and −75 °C, the as-prepared compound still owns certain zinc ion storage abilities, especially high discharge/charge capacities of 48.9/48.7 mAh g−1 can be still achieved in the 100th cycle at −75 °C (100 mA g−1). Furthermore, a full-cell with operational capability at −40 °C is also built here, and it can exhibit discharge capacity of 66.1 mAh g−1 (coulombic efficiency of 99.7 %) in the 3rd cycle and discharge capacity of 48.2 mAh g−1 (coulombic efficiency of 99.7 %) in the 50th cycle. [ABSTRACT FROM AUTHOR]

Recent research indicates a severe discrepancy between oxygen evolution reaction catalysts dissolution in aqueous model systems and membrane electrode assemblies. This questions the relevance of the widespread aqueous testing for real world application. In this study, we aim to determine the processes responsible for the dissolution discrepancy. Experimental parameters known to diverge in both systems are individually tested for their influence on dissolution of an Ir-based catalyst. Ir dissolution is studied in an aqueous model system, a scanning flow cell coupled to an inductively coupled plasma mass spectrometer. Real dissolution rates of the Ir OER catalyst in membrane electrode assemblies are measured with a specifically developed, dedicated setup. Overestimated acidity in the anode catalyst layer and stabilization over time in real devices are proposed as main contributors to the dissolution discrepancy. The results shown here lead to clear guidelines for anode electrocatalyst testing parameters to resemble realistic electrolyzer operating conditions. Dissolution of Ir catalysts varies widely between PEM water electrolysers and aqueous electrolytes. Here, we systematically investigate this finding and propose that stabilization of the catalysts over time and overestimated ionomer acidity are the main contributors to the dissolution discrepancy. [ABSTRACT FROM AUTHOR]

Purpose: Correlation of characteristic surface appearance and surface roughness with measured air kerma (kinetic energy released in air) reduction of tungsten‐rhenium (WRe) stationary anode surfaces. Methods: A stationary anode test system was developed and used to alter nine initially ground sample surfaces through thermal cycling at high temperatures. A geometrical model based on high resolution surface data was implemented to correlate the measured reduction of the air kerma rate with the changing surface appearance of the samples. In addition to the nine thermally cycled samples, three samples received synthetic surface structuring to prove the applicability of the model to nonconventional surface alterations. Representative surface data and surface roughness values were acquired by laser scanning confocal microscopy. Results: After thermal cycling in the stationary anode test system, the samples showed surface features comparable to rotating anodes after long‐time operation. The established model enables the appearance of characteristic surface features like crack networks, pitting, and local melting to be linked to the local x‐ray output at 100 kV tube voltage ,10° anode take off angle and 2 mm of added Al filtration. The results from the conducted air kerma measurements were compared to the predicted total x‐ray output reduction from the geometrical model and show, on average, less than 10 % error within the 12 tested samples. In certain boundaries, the calculated surface roughness Ra showed a linear correlation with the measured air kerma reduction when samples were having comparable damaging characteristics and similar operation parameters. The orientation of the surface features had a strong impact on the measured air kerma rate which was shown by testing synthetically structured surfaces. Conclusions: The geometrical model used herein considers and describes the effect of individual surface features on the x‐ray output. In close boundaries arithmetic surface roughness Ra was found to be a useful characteristic value on estimating the effect of surface damage on total x‐ray output. [ABSTRACT FROM AUTHOR]

Summary: Rechargeable sodium‐ion batteries are facing the challenge of highly electrochemical active anode for their realization. In this study, we report a dual coating strategy of CoS2 with metallic Co particles and carbon to boost the charge transfer and stability. The phase of CoS2 and the existence of Co metallic particles were confirmed using x‐ray diffraction (XRD). x‐ray photoelectron spectroscopy (XPS) results corroborate the presence of carbon and CoS bonding. The prepared CoS2@Co@C anode reveals high performance where it shows a capacity of 712 mA h g−1 at 0.05 C rate. The CoS2@Co@C electrode exhibits exceptional high rate capability where it exhibits a capacity of 260 mA h g−1 at elevated rate of 10.0 C. The cyclability of CoS2@Co@C anode is tested at 0.05 C and 0.5 C rates where the electrode shows 78% and 45% capacity retention of stabilized capacity. The reaction mechanism of the CoS2@Co@C electrode is determined using x‐ray absorption spectroscopy (XAS) and the results show reversibility of the material. [ABSTRACT FROM AUTHOR]

Featured Application: Authors are encouraged to provide a concise description of the specific application or a potential application of the work. This section is not mandatory. Fe2O3 and Fe2O3:Ge nanofibers (NFs) were prepared via electrospinning and thoroughly characterized via several techniques in order to investigate the effects produced by germanium incorporation in the nanostructure and crystalline phase of the oxide. The results indicate that reference Fe2O3 NFs consist of interconnected hematite grains, whereas in Fe2O3:Ge NFs, constituted by finer and elongated nanostructures developing mainly along their axis, an amorphous component coexists with the dominant α-Fe2O3 and γ-Fe2O3 phases. Ge4+ ions, mostly dispersed as dopant impurities, are accommodated in the tetrahedral sites of the maghemite lattice and probably in the defective hematite surface sites. When tested as anode active material for sodium ion batteries, Fe2O3:Ge NFs show good specific capacity (320 mAh g−1 at 50 mA g−1) and excellent rate capability (still delivering 140 mAh g−1 at 2 A g−1). This behavior derives from the synergistic combination of the nanostructured morphology, the electronic transport properties of the complex material, and the pseudo-capacitive nature of the charge storage mechanism. [ABSTRACT FROM AUTHOR]

This study presents the determination of electrochemical properties of active steel in mortar, based on inverse numerical modeling that focuses on their dependency on chloride content. An experimental campaign, consisting of galvanic coupling tests between anode samples contaminated with different chloride concentrations and cathode samples without chlorides, was carried out. Cathode polarization tests allowed for directly determining passive steel electrochemical parameters. Anode polarization tests coupled with a numerical optimization were then performed for quantifying active steel parameters and focusing on chloride's effect on the iron anodic Tafel coefficient. Furthermore, the steel electrochemical properties were successfully used as input parameters to model the galvanic experiments. [ABSTRACT FROM AUTHOR]

Hollow and dense SnS sub-microspheres constructed from self-assembled nanosheets wrapped in a nitrogen-doped carbon shell were prepared by a low-cost, facile solvothermal process followed by annealing. The lithium-ion storage capacities of the hollow and dense spheres were tested and compared as anodes in lithium-ion battery half cells. The hollow microspheres showed low internal charge transfer resistance, good buffering of volume changes during lithiation and delithiation and good rate and cycling performance. After 1000 cycles, the hollow SnS composite still delivered a capacity of 420 mA h g−1 at 1.0 A g−1, which is 2.5 times higher than that of the dense spheres. The capacity retention from the second cycle on was 84% and 75%, respectively. The superior lithium storage performance of the hollow particles arise from their pronounced porosity, hierarchical architecture from the self-assembled nanosheets and well-controlled uniform carbon shells. [ABSTRACT FROM AUTHOR]

• TiC provides a stable structure for suppressing electrode deformation and ZnO agglomeration. • The ZnO@TiC anode is able to maintain ultra-long and stable cycling performance at high rates. • The average discharge specific capacity of this work can attain 550 mAh·g−1. Alkaline zinc-nickel batteries are not properly exploited for their high-current charge and discharge characteristics that are caused by the corrosion, deformation and poor conductivity of zinc oxide for the anode. In this work, we synthesize a ZnO@TiC composite with a football-like structure. The incorporation of TiC enables the better electrical conductivity and structural stability, which reduces the agglomeration of active materials and the deformation of the electrode. Simultaneously, the discharge specific capacity of ZnO@TiC electrode reaches 520 mAh·g−1 after 1500 cycles at 6C, with a capacity retention rate of 94.5 %. Subsequently, the TiC has been introduced as an additive to the anode to test the performance in commercial 2 A zinc-nickel batteries. The results demonstrate that a moderate amount of TiC can extend the cycle life of the battery by about 50 %. This work provides a novel idea for the protection of zinc-nickel battery anodes. [ABSTRACT FROM AUTHOR]