Search

Ractopamine (RA) is a phenolic substance widely used as an animal food additive. However, excessive RA use can have adverse effects on human health. Therefore, the development of a sensor for accurate RA detection is crucial. In this study, a flexible and economical laser-induced graphene (LIG) sensor was fabricated by uniformly drop casting ZnZrO2@g-C3N4 NPs on the LIG surface. Further, the fabricated electrochemical sensor was characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), HR-SEM with EDS, HR-TEM, BET and EIS analytical techniques. Owing to the good synergistic effect of ZnZrO2@g-C3N4 and LIG, the ZnZrO2@g-C3N4/LIG electrochemical sensor exhibits brilliant RA sensitivity and rapid sensing with excellent linearity (0.01–0.15 μM), low limit of detection (0.1537 μM), high sensitivity of 0.3748 μA mM−1 cm−2, and outstanding repeatability. The sensor successfully detected RA in real samples with recoveries ranging from 96.8–103%. This study introduces a new RA detection approach that uses LIG-metal and metal oxides in electrochemical sensing. [ABSTRACT FROM AUTHOR]

A hybrid material consisting of an array of vertically ordered carbon nanotubes (CNTs) in porous anodic alumina was fabricated directly on oxidized Si substrates. Individual CNTs with vertical orientation were grown using the catalyst Ni nanoparticles (NPs) embedded in the pore walls of a thin template based on porous anodic alumina with a pore diameter of 40 ± 5 nm. The initial film was a two-layer Ti-Al structure on a Si/SiO 2 substrate. A vertically oriented porous structure was formed by anodizing the Al layer. Electrochemical deposition was used to form the catalyst Ni-NPs with dimensions of 30 ± 5 nm. CNTs were synthesized by high-temperature chemical vapor deposition. Scanning and transmission electron microscopy, Raman spectroscopy, and X-ray diffraction were used to analyze the surface morphology and microstructure of the composite nanostructures. The CNT length was (0.6–1.5) μm, and the CNT spacing was 110 ± 10 nm. It is expected that the resulting structure will serve as a basis for the development of CNT-based electrodes for electrochemical impedance biosensors. Electrochemical impedance spectroscopy was used for the electrochemical characterization of the fabricated CNT-based electrodes. The results showed that the CNT-based electrodes are characterized by improved electron transfer kinetics. [ABSTRACT FROM AUTHOR]

Protonic ceramic fuel cells (PCFCs), which are based on proton conducting electrolytes, are a class of power generation devices that can efficiently operate at the intermediate (500–700 °C), even low (450 °C) temperatures, but their development is hindered by sluggish cathodic kinetics at reduced temperatures. At the PCFC cathode, the absorbed oxygen molecules react with oxygen vacancies, protons and electrons to generate water and release electrical energy. Thus, the PCFC cathode materials require percolation network for proton, oxide-ion, and electron carriers simultaneously. In this work, we developed a triple ionic-electronic conductor BaCo 0.4 Fe 0.4 Zr 0.15 W 0.05 O 3-δ as a new cathode material for the PCFCs using BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ as the electrolyte. Anode supported cells were fabricated and the performances were investigated. Compared with the parent oxide, tungsten doping can significantly improve the electrochemical reduction kinetic of oxygen. The BaCo 0.4 Fe 0.4 Zr 0.15 W 0.05 O 3-δ based PCFC obtained the peak power density of 688 mW ⋅ cm−2 at 600 °C, which is 1.29 time higher than that of BaCo 0.4 Fe 0.4 Zr 0.2 O 3-δ based PCFC (the peak power density of 534 mW ⋅ cm−2 at 600 °C). Moreover, BaCo 0.4 Fe 0.4 Zr 0.15 W 0.05 O 3-δ has a better thermal expansion matching with the electrolyte material BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ. [Display omitted] [ABSTRACT FROM AUTHOR]

Electrochemical drilling (ECD) offers excellent potential for processing deep holes because it does not wear tools, does not create a remelting layer on the machined surface, and does not produce residual stress during machining. However, a normal single-hole tube electrode easily forms a spike at the bottom of the drilling hole, thereby destroying the flatness at the bottom. This phenomenon is clearly visible when drilling blind holes with large diameters. In this study, a tube electrode with multiple outlet holes is proposed to eliminate the spike and improve the flatness at the bottom of the hole. Specifically, a single outlet hole was discretized into multiple small-diameter outlet holes. The effects of the arrangement of the outlet holes on the electric field distribution over the workpiece surface and the flow field distribution in the machining gap were numerically investigated. The results generated according to the electric field showed that the outlet holes should be as small as possible and appropriately overlap to flatten the surface. The results generated according to the flow field indicated that increasing the number of outlet holes and their overlap ratio increased the electrolyte flow rate, but it also caused the flow fields to interfere with each other, resulting in an uneven distribution. Different tools were experimentally verified using stainless steel 20Cr13, and the stability of the process and machining quality were analyzed. The results showed that, for the given test parameters, higher machining quality and processing stability were obtained using a tool with 16 non-overlapping outlet holes. Furthermore, the discrete tube electrode was optimized using chamfered outlet holes. For a voltage of 25 V, feed speed of 0.8 mm/min, and electrolyte pressure of 0.2 MPa, a deep blind hole with a diameter of 22.43 ± 0.04 mm and depth of 71.28 mm was machined using the optimal tool, which had a roundness of 0.0201 mm, flatness of 52.46 µm, and taper of 0.1296°. [ABSTRACT FROM AUTHOR]

In this study, a novel nanocomposite material consisting of Bi 2 O 3 and Bi 2 MoO 6 , named as Bi 2 O 3 @Bi 2 MoO 6 , was successfully fabricated by co-precipitation method in ethylene glycol solvent. Morphological analysis of the heat-treated sample at 400 °C for 12 h in Ar atmosphere (Bi 2 O 3 @Bi 2 MoO 6 _400 °C) showed that it contained nano-sized particles of Bi 2 O 3 and Bi 2 MoO 6 ; in addition, an amorphous phase along with a crystalline structure was also observed. When used as an anode for Li-ion batteries (LIBs), Bi 2 O 3 @Bi 2 MoO 6 _400 °C anode exhibits excellent electrochemical properties such as high Coulombic efficiency, high specific capacity, excellent capacity retention, and outstanding rate capacity. Specifically, the Bi 2 O 3 @Bi 2 MoO 6 _400 °C anode presented a reversible capacity of 786 mAh g−1 at the beginning cycle at 0.1 A g−1 and retained about 90 % of the charging capacity value after 80 cycles. The advanced electrochemical properties of the nanocomposite anode are related to the combination of many aspects such as nanostructure, existence of amorphous phase, and pseudo-behaviour of metal-based components. The structural stability and electrochemical performance of the anode material, therefore, are improved. These results demonstrate Bi 2 O 3 @Bi 2 MoO 6 _400 °C as a promising material for establishing high-performance LIB anodes. [Display omitted] • Bi 2 O 3 @Bi 2 MoO 6 powders are prepared by a facile method. • Bi 2 O 3 @Bi 2 MoO 6 powders contain amorphous and crystalline phases. • Bi 2 O 3 @Bi 2 MoO 6 materials possess nanostructures (from 20 nm to 50 nm). • Bi 2 O 3 @Bi 2 MoO 6 _400 °C anode displays high initial coulombic efficiency (>80 %). • Bi 2 O 3 @Bi 2 MoO 6 _400 °C anode shows a reversible capacity of 701 mAh g−1 after 80 cycles. [ABSTRACT FROM AUTHOR]

This paper presents a study on the impedance spectroscopy methods applied to 2-electrode and 3-electrode biosensors. While 3-electrode electrochemical biosensors have been extensively studied and applied in various applications, the 2-electrode configuration of electrochemical biosensors still lacks comprehensive investigation for real-world applications. In particular, the miniaturization of the 3-electrode configuration for integration into microfluidic devices has been explored due to the relatively limited number of previous studies. A commercial screen-printed gold electrode was employed to develop immunosensors for bovine serum albumin (BSA) detection. The comparisons were performed on non-Faradaic and Faradic immunosensors corresponding to 2-electrode and 3-electrode configurations through impedance measurements. The results show the performance of both types of sensors in detecting BSA protein. While the 2-electrode configuration-based sensor can detect the BSA protein with a sensitivity of 12 Ω/µM, the 3-electrode configuration-based sensor shows superior results with a sensitivity of 7.2 kΩ/µM. Besides, the results also indicate that the 2-electrode configuration-based sensor can easily be miniaturized to integrate into a microfluidic channel to develop lab-on-a-chip systems. Although the 3-electrode configuration demonstrates advancements compared to the 2-electrode configuration, the 2-electrode system based on non-Faradaic processes still shows high potential for future applications. [ABSTRACT FROM AUTHOR]

A novel cobalt-free, high-nickel cathode material, named 0.01B-LiNi 0.98 Mg 0.01 Zr 0.01 O 2 (NMZB), is introduced, aimed at enhancing stability. Mg, Zr, and B elements are strategically incorporated, with Mg and Zr primarily located inside particles and B predominantly on the surface, boosting both bulk and surface stability. NMZB exhibits outstanding electrochemical performance, with 90.5% capacity retention after 200 cycles at a 1C rate. This composition offers a pathway for cost-effective, high-performance lithium-ion battery technology. [Display omitted] Cobalt-free, high-nickel cathode materials are essential for the sustainable evolution of energy storage technologies, reducing the dependence on resources with significant environmental and social implications and simultaneously improving the efficiency and cost effectiveness of batteries. This paper introduces a cobalt-free, high-nickel cathode material called 0.01B-LiNi 0.98 Mg 0.01 Zr 0.01 O 2 (NMZB) developed using a novel blend of elements to enhance mechanical and surface chemical stability. Detailed evaluations confirmed the successful integration of Mg, Zr, and B into the particles, with Mg and Zr primarily located within the particle interior and B predominantly on the surface. This unique elemental configuration significantly improves the stability of the bulk phase and surface structure of the material. In addition, the refinement of primary particles within NMZB further enhances its mechanical stability. As a result, NMZB exhibits exceptional electrochemical stability, achieving 90.5 % capacity retention after 200 cycles at a 1C rate. This compositional strategy incorporates a high nickel content into layered materials while eliminating cobalt, which is crucial for advancing the development of cost effective and high-performance lithium-ion battery technology. [ABSTRACT FROM AUTHOR]

Solid–state batteries based on Li7La3Zr2O12 (LLZO) garnet electrolyte are a robust and safe alternative to conventional lithium‐ion batteries. However, the large‐scale implementation of ceramic composite cathodes is still challenging due to a complex multistep manufacturing process. A new one‐step route for the direct synthesis of LLZO during the manufacturing of LLZO/LiCoO2 (LCO) composite cathodes based on cheap precursors and utilizing the industrially established tape casting process is presented. It is shown that Al, Ta:LLZO can be formed directly in the presence of LCO from metal oxide precursors (LiOH, La2O3, ZrO2, Al2O3, and Ta2O5) by heating to 1050 °C, eliminating the time‐ and energy‐consuming synthesis of preformed LLZO powders. In addition, performance‐optimized gradient microstructures can be produced by sequential casting of slurries with different compositions, resulting in dense and flat phase‐pure cathodes without unwanted ion interdiffusion or secondary phase formation. Freestanding cathodes with a thickness of 85 µm, a relative density of 95%, and an industrial relevant LCO loading of 15 mg show an initial capacity of 82 mAh g−1 (63% of the theoretical capacity of LCO) in a solid‐state cell with Li metal anodes, which is comparable to conventional LCO/LLZO cathodes and can be further improved in the future. [ABSTRACT FROM AUTHOR]

Chemically modified graphene is an attractive electrode material for electrocatalysis, energy devices, and sensors, whereas pristine graphene is electrochemically passive. The remarkable anisotropic electrochemical nature of graphene is uncovered by π–π interaction, making pristine graphene more active than bare Au. The π–π stacking during redox reaction "dopes" the graphene, disrupting the passivating hydration layer, making it a facile electrochemical electrode. The structure during π–π stacking‐mediated redox of methylene blue (MB) is quantitatively measured by the differential reflectivity of a polarized laser on a ≈100 micron spot. The local redox reaction current varies over fourfold due to the orientation of the ≈10 micron size grains. The mosaic‐grain anisotropy on each spot shows local uniaxial orientation. The redox signal at the optimum orientation is over 2.5‐fold greater than that for bare Au on the same electrode. The redox signal is over fivefold greater at the edges of graphene compared bare Au. Remarkably, the π–π interaction increases chemical stability significantly, leading to negligible photo‐degradation at the approximate absorption wavelength of MB. The exclusive redox activity due to π–π interaction on pristine graphene adds to the toolbox of making exotic opto‐electrochemical electrode materials for electrocatalysis, sensing, and electronics. [ABSTRACT FROM AUTHOR]

Flexible lithium-ion batteries (LIBs) are receiving widespread attention, and how to obtain the high flexibility, safety, and energy density of LIBs at the same time are one of the main challenges in the field of flexible electronics. The multi-network structure formed by cellulose nanofiber (TOCNF) not only provided sufficient mechanical support and excellent flexibility for the electrode but also promoted uniform distribution of conductive agents and active materials. In this work, we prepared an eco-friendly TOCNF binder from wheat straw, using a method involving 2, 2, 6, 6-tetramethylpiperidinyl-1-oxyl oxidation and high-intensity ultrasonic treatment. Additionally, we enhanced the performance of TOCNF by introducing Li+ through ion exchange, resulting in lithium-functionalized cellulose nanofibers (TOCNF-Li), which were employed as a novel binder for LiFePO4 cathodes. The findings show that, when employing TOCNF-Li binder, batteries were able to obtain an initial discharge capacity of 163 mAh g–1 at 0.1 C rate and maintained 93.2% of the initial reversible capacity after 400 cycles at 2 C rate. Notably, at 5 C rate, the discharge capacity reached 133.7 mAh g−1, with a capacity decay of only 16.1%. TOCNF-Li played a role in increasing Li+ content, opening a new pathway for Li+ transport, consequently enhancing Li+ diffusion efficiency and charge–discharge performance. Overall, TOCNF-Li serves as a novel, environmentally friendly, and efficient binder for flexible LIBs. [ABSTRACT FROM AUTHOR]

Ozonation water treatment technology has attracted increasing attention due to its environmental benign and high efficiency. Rutile PbO2 is a promising anode material for electrochemical ozone production (EOP). However, the reaction mechanism underlying ozone production catalyzed by PbO2 was rarely studied and not well‐understood, which was in part due to the overlook of the electrochemistry‐driven formation of oxygen vacancy (OV) of PbO2. Herein, we unrevealed the origin of the EOP activity of PbO2 starting from the electrochemical surface state analysis using density functional theory (DFT) calculations, activity analysis, and catalytic volcano modeling. Interestingly, we found that under experimental EOP potential (i. e., a potential around 2.2 V vs. reversible hydrogen electrode), OV can still be generated easily on PbO2 surfaces. Our subsequent kinetic and thermodynamic analyses show that these OV sites on PbO2 surfaces are highly active for the EOP reaction through an interesting atomic oxygen (O*)‐O2 coupled mechanism. In particular, rutile PbO2(101) with the "in‐situ" generated OV exhibited superior EOP activities, outperforming the (111) and (110) surfaces. Finally, by catalytic volcano modeling, we found that PbO2 is close to the theoretical optimum of the reaction, suggesting a superior EOP performance of rutile PbO2. All these analyses are in good agreement with previous experimental observations in terms of EOP overpotentials. This study provides the first volcano model to explain why rutile PbO2 is among the best metal oxide materials for EOP and provides new design guidelines for this rarely studied but industrially promising reaction. [ABSTRACT FROM AUTHOR]

Herein, we present a quick and cost-effective electrodeposition method to synthesize binder-free cobalt oxide (Co3O4) nanostructures. The structural crystallinity of the prepared electrodes was examined using X-ray diffraction (XRD), while Fourier-transform infrared spectroscopy (FTIR) was used to study the stretching and bending vibrations of metal–oxygen bonds. Scanning electron microscopy (SEM) revealed that as the concentration increased from 1 mM, nanoparticles transitioned from agglomeration to sheet formation. The supercapacitor properties of these Co3O4 nanostructure electrodes were investigated in a 6 M KOH solution. Among the electrodes, Co3O4@FNF-1 exhibited the highest capacitance of 1444 F g−1 at a current density of 0.5 A g−1. Additionally, the optimized Co3O4@FNF-1 electrode demonstrated 96% stability after 8000 cycles and showed excellent glucose sensing capabilities. These findings suggest that the binder-free Co3O4 electrode is a promising candidate for high-performance supercapacitor and biosensing applications. [ABSTRACT FROM AUTHOR]

Lithium sulfide (Li2S) is a promising electrode material with high specific capacity and can be paired with commercial anode materials such as graphite. However, bulk Li2S requires a high activation energy during the initial charge due to its inert electrochemical activity, resulting in high charge overpotential. Here, lithium phenyl selenide (PhSeLi) is proposed as a mediator that can effectively activate Li2S by altering the oxidation pathway in the initial charge process. It enables Li2S to release normal capacity over the general voltage range (1.5–3 V). The composite cathode with the Li2S:PhSeLi molar ratio of 4:1 exhibits a high reversible capacity of 615.9 mAh g−1 at 0.2 A g−1 after 400 cycles in all‐solid‐state batteries with Li7P3S11 sulfide electrolyte and In–Li anode (the corresponding capacity based on Li2S is 1016.6 mAh g−1). In a full cell with a partially pre‐lithiated silicon anode, it can still provide an average discharge capacity of 524 mAh g−1 at 0.1 A g−1 (the capacity based on Li2S is 844.2 mAh g−1). This work will contribute to the further development of Li2S‐based all‐solid‐state Li–S batteries. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur (Li‐S) batteries, with their high theoretical energy density and cost‐effectiveness, have become one of the most promising next‐generation energy storage devices. However, they still face challenges such as the “shuttle effect” caused by the dissolution of polysulfide intermediates and the slow sulfur conversion kinetics. In this study, based on the Co7Fe3 alloy catalyst, additional Co metal is introduced to form a Co7Fe3Co catalyst with a heterostructure through a simple heat treatment process. This catalyst is incorporated into Ketjenblack (KB) to form a sulfur‐infused cathode material (designated as S/KB/Co7Fe3Co). Li‐S batteries using S/KB/Co7Fe3Co as the cathode demonstrate outstanding electrochemical performance, maintaining a reversible specific capacity of over 500 mAh g−1 after 1000 cycles at a current density of 1 C, with a capacity decay rate of 0.046% per cycle. DFT theoretical calculations and experimental results both reveal that the introduction of additional Co effectively regulates the d‐band center of the material, enhancing the adsorption of polysulfide intermediates by Co7Fe3Co and promoting bidirectional catalytic sulfur conversion. This work highlights the importance of the simple construction of heterostructured catalytic materials and their role in improving the performance of Li‐S batteries. [ABSTRACT FROM AUTHOR]

Electrospun is a unique technique for the fabrication of multiscale structured nanofibers (MSNFs), which can be used as functional units for improving the performance of lithium‐based batteries. This review systematically examines how MSNFs, including core–shell, hollow porous, multichannel, wire‐in‐tube, tube‐in‐tube, and hierarchical nanofibers, effectively improve battery performance as components in lithium‐based batteries. The application of aforementioned MSNFs and their chemical modification contributes to the development of lithium‐based batteries with high energy density and enhanced safety when used as electrodes, separators, and electrolytes. Specifically, MSNFs are used to derive electrodes and electrolytes that improve electron/ion transfer rates, increase the utilization ratio of active materials, suppress dendrite growth, and mitigate volume expansion, enabling fast and stable electrochemical reactions at the electrodes. Additionally, MSNFs‐derived separators, which feature more ion transport channels, exceptional mechanical properties, and the capability to inhibit thermal runaway, are also discussed. Finally, the challenges and prospective pathways for electrospun technology in the application of lithium‐based batteries are reviewed. [ABSTRACT FROM AUTHOR]

Sub‐nanoclusters with ultra‐small particle sizes are particularly significant to create advanced energy storage materials. Herein, Sn sub‐nanoclusters encapsulated in nitrogen‐doped multichannel carbon matrix (denoted as Sn‐SCs@MCNF) are designed by a facile and controllable route as flexible anode for high‐performance potassium ion batteries (PIBs). The uniformly dispersed Sn sub‐nanoclusters in multichannel carbon matrix can be precisely identified, which ensure us to clarify the size influence on the electrochemical performance. The sub‐nanoscale effect of Sn‐SCs@MCNF restrains electrode pulverization and enhances the K+ diffusion kinetics, leading to the superior cycling stability and rate performance. As freestanding anode in PIBs, Sn‐SCs@MCNF manifests superior K+ storage properties, such as exceptional cycling stability (around 331 mAh g−1 after 150 cycles at 100 mA g−1) and rate capability. Especially, the Sn‐SCs@MCNF||KFe[Fe(CN)6] full cell demonstrates impressive reversible capacity of around 167 mAh g−1 at 0.4 A g−1 even after 200 cycles. Theoretical calculations clarify that the ultrafine Sn sub‐nanoclusters are beneficial for electron transfer and contribute to the lower energy barriers of the intermediates, thereby resulting in promising electrochemical performance. Comprehensive investigation for the intrinsic K+ storage process of Sn‐SCs@MCNF is revealed by in situ analysis. This work provides vital guidance to design sub‐nanoscale functional materials for high‐performance energy‐storage devices. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are selective electrocatalysts for oxygen evolution reactions (OER) owing to their high specific surface area, rich pore structure, and so on. Herein, a series of Fe/FeCo-based MOFs were developed over nickel foam (NH 2 -MIL-101-Fe@NF / NH 2 -MIL-101-(CoFe)@NF-X) employing a facile process. An overpotential of 376 mV was observed at 100 mA cm−2 for Fe-MOF. The structural modification with the addition of Co for FeCo-MOFs can improve the morphology as well as the electrochemical performance. Among of them, NH 2 -MIL-101-(CoFe)@NF-2 illuminates an excellent overpotential 329 mV with a small Tafel slope of 50 mV dec−1 at 100 mA cm−2. Its surface roughness facilitates the deep penetration of electrolyte to the internal structure of the electrode. Theoretical calculations confirmed the introduction of Co can reduce the overpotential from 0.68 V to 0.34 V at the rate-determining step (from O∗ to OOH∗). This is a key feature that promotes the electrochemical performance of OER catalysts. Improved electronic structures of Fe-based MOFs by the controllable introduction of Co, and the OER performance of NH 2 -MIL-101-(CoFe)@NF-2 was excellent, with an overpotential of 329 mV at 100 mA cm−2, which has exceeded that of most reported MOFs catalysts for electrocatalytic OER. [Display omitted] • A series of Fe/FeCo-based MOFs were in-situ grown on NF by a one-step method. • The doping of cobalt ions increases the number of exposed active sites. • NH 2 -MIL-101-(CoFe)@NF-2 only a small overpotential of 329 mV at 100 mA cm−2. • It exhibits excellent stability at the current density of 50 mA cm−2 for 28 h. • The DFT calculations further confirm the positive effect of Co. [ABSTRACT FROM AUTHOR]

The anode is the key material that constrains the performance of solid oxide electrolysis cells (SOECs). Here, we have developed self-assembled Sm 0.5 Sr 0.5 CoO 3-δ -Ce 0.8 Sm 0.2 O 2-δ (SSC-SDC) composite by the co-synthesis strategy and studied its electrochemical performance as the anode for SOECs. The surface and interface properties of the self-assembled SSC-SDC composite were systematically studied. The SDC lattice expansion and the SSC lattice contraction of the SSC-SDC composite have been shown by XRD analysis, ascribed to the strong cation interdiffusion during the self-assembly process. The self-assembled SSC-SDC also exhibits superior oxygen evolution activity and displays a larger oxygen desorption peak than the physically mixed SSC&SDC. A higher proportion of adsorbed oxygen species on the surface of the self-assembled SSC-SDC than the physically mixed SSC&SDC also have been shown by XPS results. The cell with the self-assembled SSC-SDC as anode exhibits ca. 2.1 times higher current density than the physically mixed SSC&SDC as anode. Meanwhile, the polarization resistance of the cell with self-assembled SSC-SDC as the anode is 0.0957 Ω cm2, which is only 40 % of that observed in the cell where SSC and SDC are physically mixed as the anode. This novel self-assembly strategy shows great potential for preparing high-performance oxygen electrodes. [ABSTRACT FROM AUTHOR]

Industrial applications of microbial electrochemical systems will require regular maintenance shutdowns, involving inspections and component replacements to extend the lifespan of the system. Here, we examined the impact of such shutdowns on the performance of three electrode materials (i. e., platinized titanium, graphite, and nickel) as cathodes in a microbial electrochemical system that would be used for electromethanogenesis in power‐to‐gas applications. We focused on methane (CH4) production from hydrogen (H2) and carbon dioxide (CO2) using Methanothermobacter thermautotrophicus. We showed that the platinized titanium cathode resulted in high volumetric CH4 production rates and Coulombic efficiencies. Using a graphite cathode would be more cost‐effective than using the platinized titanium cathode in microbial electrochemical systems, but showed an inferior performance. The microbial electrochemical system with the nickel cathode showed improvements compared to the graphite cathode. Additionally, this system with a nickel cathode demonstrated the fastest recovery during a shutdown experiment compared to the other two cathodes. Fluctuations in pH and nickel concentrations in the catholyte during power interruptions affected CH4 production recovery in the system with the nickel cathode. This research enhances understanding of the integration of biological and electrochemical processes in microbial electrochemical systems, providing insights into electrode selection and operating strategies for effective and sustainable CH4 production. [ABSTRACT FROM AUTHOR]

Lithium‐metal solid‐state batteries are attractive as next generation of Li‐ion batteries due to higher safety and potentially higher energy density. To improve processability, solid‐composite separators combine advantages of inorganic and polymer separators in hybrid structure. We report a systematic approach to fabricate composite separators with high content (90–95 wt %) of ceramic Li‐ion conducting Li6.45Al0.05La3Zr1.6Ta0.4O12 (LLZO) powder embedded in a polyethylene oxide (PEO)‐LiTFSI (20 : 1) matrix and understand factors affecting their properties and performance. Separators with good mechanical flexibility and excellent thermal stability were obtained, by optimizing materials and processing parameters. It was found that PEO molecular weight strongly influences the microstructure and electrochemical properties of the separators. In optimized separator with 90 wt % of LLZO and PEO with Mw 300,000 g/mol, a total ionic conductivity of 1.4×10−5 S/cm at 60 °C was achieved. The ceramic‐rich separator showed excellent long‐term cycling stability for more than 460 cycles (1000 h) at 0.1 mA/cm2 in Li/Li symmetrical cells and achieved a critical current density of 0.25 mA/cm2. The separators also enabled initial discharge capacities of more than 160 mAh/g in full cells with Li metal anode and composite solid‐state LiNi0.6Co0.2Mn0.2O2 cathode, although rapid capacity fade was observed after 10 cycles in fully solid‐state configuration. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a density-based topology optimization framework to design porous electrodes for maximum energy storage. We simulate the full cell with a model that incorporates electronic potential, ionic potential, and electrolyte concentration. The system consists of three materials, namely pure liquid electrolyte and the porous solids of the anode and cathode, for which we determine the optimal placement. We use separate electronic potentials to model each electrode, which allows interdigitated designs. As a result, a penalization is required to ensure that the anode and cathode do not touch, i.e., causing a short circuit. We compare multiple 2D designs generated for different fixed conditions, e.g. material properties. A 3D design with complex channel and interlocked structure is also created. All optimized designs are far superior to the traditional monolithic electrode design with respect to energy storage metrics. We observe up to a 750% increase in energy storage for cases with slow effective ionic diffusion within the porous electrode. [ABSTRACT FROM AUTHOR]

Lithium‐metal anodes (LMAs) are the ultimate choice for realizing high‐energy‐density batteries; however, its use is hindered by problematic Li growth in the form of dendrites. To alleviate dendritic Li growth, the preparation of LMAs with a lithiophilic current collector (CC) is effective; however, applying a lithiophilic CC to LMAs is still challenging due to the manufacturing complexity involved in the separate lithiophilic treatment and lithiation processes. Herein, a facile one‐pot LMA fabrication method by utilizing thiourea (TU) as a precursor is proposed. A lithiophilic Cu2S layer is formed on Cu foam (CF) by the in situ electrochemical oxidation of TU (CuxSCF), and the lithiation of CC is performed via subsequent Li electrodeposition (Li@CuxSCF). The Cu2S on CuxSCF can lead to uniform Li deposition by providing lithiophilic sites, and it is converted to form ionic‐conductive Li2S‐rich solid electrolyte interphase layer. Resultantly, CuxSCF significantly enhances the cycling performance of LMAs compared to CF. Specifically, a LiFePO4/Li@CuxSCF full‐cell lithium‐metal battery (LMB) with a low n/p ratio (1.6) exhibits capacity retention of 95.6% at 0.5 C (220 cycles) and can maintain 85.0% of initial capacity (425 cycles, n/p = 4) at 2.0 C. LMBs with LiNi0.6Co0.2Mn0.2 and LiNi0.8Co0.1Mn0.1 also exhibit improved electrochemical performance. [ABSTRACT FROM AUTHOR]

High‐entropy materials have drawn much attention as battery materials due to their distinctive properties. Lithiated high‐entropy oxide (Li0.33(MgCoNiCuZn)0.67O, LiHEO) exhibits both high lithium‐ion and electronic conductivity, making it a potential coating material for layered Ni‐rich oxide cathodes (Li1+x(Ni1−y−zCoyMnz)1−xO2, NCM or NMC) in conventional Li‐ion battery cells; however, high‐temperature synthesis limits its application. Therefore, a photonic curing strategy is used for synthesizing LiHEO and the non‐lithiated form (denoted as high‐entropy oxide [HEO]), and nanoscale coatings are successfully produced on LiNi0.85Co0.1Mn0.05O2 (NCM851005) particles. To one's knowledge, this is the first report on particle coating with high‐entropy materials using photonic curing. NCM851005 with LiHEO‐modified surface shows good cycling stability, with a capacity retention of 97% at 1 C rate after 200 cycles. The improvement in electrochemical performance is attributed to the conformal coating that prevents structural changes caused by the reaction between cathode material and liquid electrolyte. Compared to bare NCM851005, the coated material shows a significantly reduced tendency for intergranular cracking, successfully preventing electrolyte penetration and suppressing side reactions. Overall, photonic curing presents a novel cost‐ and energy‐efficient synthesis and coating procedure that paves the way for surface modification of any heat‐sensitive material for a wide range of applications. [ABSTRACT FROM AUTHOR]

In this study, a highly sensitive electrochemical sensor for the detection of bisphenol A (BPA) was developed by modifying a screen-printed carbon electrode (SPCE) with silver nanoparticles (AgNPs) and graphene oxide (GO) composites. The electrochemical properties of the modified electrode interface were meticulously investigated through cyclic voltammetry (CV) and electrochemical impedance spectroscopy, employing 1.0 mM [Fe(CN)6]3–/[Fe(CN)6]4– as a redox probe. The findings demonstrate that the AgNPs/GO/SPCE composite exhibits superior electrical conductivity and facilitates rapid electron transfer compared to both GO/SPCE and SPCE alone. The electrochemical behavior of BPA on the AgNPs/GO/SPCE electrode was comprehensively studied using CV, revealing exceptional electrocatalytic properties for BPA oxidation. To assess the analytical performance, differential pulse voltammetry was employed. Results unequivocally show a significant improvement in the electrochemical responses when using AgNPs/GO/SPCE. Calibration curves exhibited linear ranges of 0.25–2.19 μM with a remarkable limit of detection of 0.046 μM for BPA. Furthermore, the established method was applied for the determination of BPA in plastic products, achieving satisfactory reproducibility and recovery. This novel AgNPs/GO/SPCE-based sensor holds promise for the sensitive and reliable detection of BPA in various environmental and industrial applications. [ABSTRACT FROM AUTHOR]

Thallium (Tl), a heavy metal, has potentially harmful effects on human health due to its extreme toxicity. The determination of Tl is critical, and thus, there is a need for the development of electrochemical sensors that can swiftly identify its presence in the environment. A one-step hydrothermal synthesis of Prussian blue (PB) was utilized to adsorb thallium and electrochemically activate PB. The structure and morphology of PB were characterized through a scanning electron microscope, X-ray energy spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The PB-modified electrode's determination performance was optimized using the square wave voltammetry method. This included the optimization of support electrolyte, pH, deposition potential, and deposition time. Under optimal experimental conditions, the electrode demonstrated a favorable electrochemical response to thallium concentrations between 10 and 500 μg/L, with a detection limit of 1.94 μg/L. In summary, this sensor's outcomes are satisfactory and enhance the utility of PB nanomaterials in electrochemically detecting the heavy metal Tl. [ABSTRACT FROM AUTHOR]

This research investigates the utilization of a modified Ti/nano ZnO-Bi2O3 electrode for the electrochemical advanced oxidation-based removal of a pharmaceutical pollutant from an aqueous solution. To analyze the surface properties of Ti/nano ZnO, Ti/nano Bi2O3, and Ti/nano ZnO-Bi2O3 electrodes made using electrophoretic deposition, various analytical methods were used. These methods included X-ray diffraction analysis, energy-dispersive spectroscopy, and field emission scanning electron microscopy confirmed the presence of ZnO nanoparticles and Bi2O3 nanoparticles in a layer that is uniformly coated on the Ti/nano ZnO-Bi2O3 electrode. Beside linear sweep voltammetry and Tafel plots confirmed the increased stability and electrocatalytic activity of the modified electrode compared to the initial electrode. Chronopotentiometry and chronoamperometry verified the stability and better conductivity of the nanocomposite electrode, and according to electrochemical impedance spectroscopy, charge transfer in the modified electrode has improved by 87%. We evaluated the effectiveness of the Ciprofloxacin removal process by considering factors, such as pH in the range of 3–11, electrolyte concentration in the range of 1–7 g L−1, and current density in the range of 1.2–5.75 mA cm−2. We selected Ciprofloxacin as the specific pollutant for evaluating pollutant removal from aqueous solutions due to its widespread use and presence in the environment. We determined the optimal parameter values to be 6.25 mA cm−2, 5, and 3 g L−1. Under these optimal conditions, the efficiency of ciprofloxacin removal reached 96.33% within 300 min. [ABSTRACT FROM AUTHOR]

[Display omitted] Electrocatalytic water splitting (EWS) for hydrogen production is considered an ideal strategy for utilizing renewable energy, reducing fossil fuel consumption, and addressing environmental pollution issues. Traditional noble metal electrocatalysts have excellent performance, but their cost is high. Developing efficient, stable, and relatively inexpensive dual functional electrocatalysts is crucial for promoting large-scale EWS hydrogen production processes. Herein, a simple one-step electrodeposition method was used to grow nickel–iron phosphorus-sulfides (NiFePS) on the surface of hydrophilic treated carbon cloth (CC). The resultant NiFePS/CC with a phosphorus to sulfur ratio of 1:4 exhibited the best electrocatalytic performance, requiring only −91 mV and 216 mV overpotentials to generate the current densities of 10 mA·cm−2 in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. When it was used as a bifunctional electrocatalyst to overall water splitting (OWS), a voltage of 1.536 V can generate a current density of 10 mA·cm−2. The excellent electrocatalytic performance can be ascribed to two factors: 1) the CC with excellent conductivity serves as a growth substrate, reducing the impedance of charge transfer from the electrode to the electrolyte and accelerating the electron transfer rate; 2) The large number of ultra-thin nanosheets formed on the surface of the catalyst increase the electrochemical specific surface area, expose more reaction sites, and thus improve the electrocatalytic reaction performance. This work provides a new approach for designing efficient non-noble metal electrocatalysts for water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] The orientation-guidance coupled with in-situ activation methodology is developed to synthesize the N -doped porous carbon (NPC) with well-developed porosity and high specific surface area, using coal pitch as a carbon precursor. The orientation-guidance and activation are dedicated to generating microporous and mesoporous channels, respectively. The in-situ N incorporation into the carbon skeleton is realized along with the formation of porous carbon (PC), ensuring the uniformity of N doping. As an electrode material of supercapacitor, benefiting from the robust hexagon-like building block decorated with micro-mesoporous channels and N doping, NPC electrode affords a significant improvement in capacitive energy-storage performance, achieving a specific capacitance of up to 333F g−1 at 1 A/g, which far exceeds those of PC and activated carbon. Notably, even under high mass loading of 10 mg cm−2, the NPC maintains a satisfactory capacitance of 258F g−1 at 1 A/g. When employed as the anode in Li-ion capacitor (LIC), apart from exhibiting enhanced anode behavior compared to graphite anode, NPC also delivers exceptional cyclability. Furthermore, density functional theory calculations have validated the enhanced electrical conductivity and Li storage ability contributed by N doping, providing a theoretical foundation for the observed improvements in electrochemical performance. A full LIC configured with NPC anode delivers extraordinary Ragone performance and outstanding cyclability. This work also proposes a feasible way to realize the oriented conversion of coal pitch into high-performance electrode materials for electrochemical energy-storage devices. [ABSTRACT FROM AUTHOR]

This study focuses on developing high-performance electrodes by applying micro/nano structures to aluminum mesh electrodes and evaluating their electrochemical performance through the electroflotation process. First, the most suitable electrode material for electroflotation was selected, followed by the application of micro-nano structures to analyze bubble generation and size distribution in comparison to conventional electrodes. The bubble generation rate and size were used to predict electroflotation efficiency, which was then validated through experiments. The developed electrodes demonstrated a ninefold reduction in purification time compared to traditional electrodes and achieved higher wastewater treatment efficiency than spontaneous flotation. This research highlights the potential of micro-nano structured electrodes to enhance electroflotation processes and offers valuable insights for industrial applications. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) occurs at the cathode of electrochemical devices like fuel cells and in the Huron-Dow process, reducing oxygen to water or hydrogen peroxide. Over the past years, various electrocatalysts with enhanced activity, selectivity, and durability have been developed for ORR. However, an atomic-level understanding of how materials composition affects electrocatalytic performance has not yet been achieved, which prevents us from designing efficient catalysts based on the requirements of practical applications. This is partially because of the polydispersity of traditional catalysts and their unknown structure dynamics in the electrocatalytic reactions. Here we establish a full-spectrum of atomically precise and robust AuxAg25-x(MHA)18 (x = 0–25, and MHA = 6-mercaptohexanoic acid) nanoclusters (NCs) and systematically investigate their composition-dependent catalytic performance for ORR at the atomic level. The results show that, with the increasing number of Au atoms in AuxAg25-x(MHA)18 NCs, the electron transfer number gradually decreases from 3.9 for Ag25(MHA)18 to 2.1 for Au25(MHA)18, indicating that the dominant oxygen reduction product alters from water to hydrogen peroxide. Density functional theory simulations reveal that the Gibbs free energy of OOH adsorption (ΔGOOH*) on Au25 is closest to the ideal ΔGOOH* of 4.22 eV to produce H2O2, while Ag alloying makes the ΔGOOH* deviate from the optimal value and leads to the production of water. This study suggests that alloy NCs are promising paradigms for unveiling composition-dependent electrocatalytic performance of metal nanoparticles at the atomic level. [ABSTRACT FROM AUTHOR]

Sulfide‐based inorganic solid electrolytes are promising materials for high‐performance safe solid‐state batteries. The high ion conductivity, mechanical characteristics, and good processability of sulfide‐based inorganic solid electrolytes are desirable properties for realizing high‐performance safe solid‐state batteries by replacing conventional liquid electrolytes. However, the low chemical and electrochemical stability of sulfide‐based inorganic solid electrolytes hinder the commercialization of sulfide‐based safe solid‐state batteries. Particularly, the instability of sulfide‐based inorganic solid electrolytes is intensified in the cathode, comprising various materials. In this study, carbonate‐based ionic conductive polymers are introduced to the cathode to protect cathode materials and suppress the reactivity of sulfide electrolytes. Several instruments, including electrochemical spectroscopy, X‐ray photoelectron spectroscopy, and scanning electron microscopy, confirm the chemical and electrochemical stability of the polymer electrolytes in contact with sulfide‐based inorganic solid electrolytes. Sulfide‐based solid‐state cells show stable electrochemical performance over 100 cycles when the ionic conductive polymers were applied to the cathode. [ABSTRACT FROM AUTHOR]

The article delves into the synthesis and characterization of MoS2-carbon-based materials, holding promise for applications in supercapacitors and ion batteries. The synthesis process entails the preparation of MoS2 and its carbon hybrids through exfoliation, hydrothermal treatment, and subsequent pyrolysis. Various analytical techniques were employed to comprehensively examine the structural, compositional, and morphological properties of the resulting materials. The article explores the electrochemical performance of these electrode materials in supercapacitors and ion batteries (LiB, SiB, KiB). Electrochemical measurements were conducted in aqueous electrolyte for supercapacitors and various aprotic electrolytes for ion batteries. Results highlight the impact of the synthesis process on electrochemical performance, emphasizing factors such as capacitance, rate capability, and charge/discharge cycle performance. Hydrothermally treated MoS2-carbon exhibited a specific capacitance of approximately 150 F g-1 in supercapacitors, attributed to its high surface area and efficient charge storage mechanisms. Additionally, for Li-ion battery materials without hydrothermal treatment showed impressive capacity retention of around 88% after 500 charge-discharge cycles, starting with an initial specific capacity of about 920 mAh/g. Long-term stability was demonstrated in both supercapacitors and lithium-ion batteries, with minimal capacitance degradation even after extensive charge-discharge cycles. This research underscores the potential of MoS2-based materials as effective energy storage solutions. [ABSTRACT FROM AUTHOR]

Copper-based materials play a vital role in the electrochemical transformation of CO2 into C2/C2+ compounds. In this study, cross-sectional octahedral Cu2O microcrystals were prepared in situ on carbon paper electrodes via electrochemical deposition. The morphology and integrity of the exposed crystal surface (111) were meticulously controlled by adjusting the deposition potential, time, and temperature. These cross-sectional octahedral Cu2O microcrystals exhibited high electrocatalytic activity for ethylene (C2H4) production through CO2 reduction. In a 0.1 M KHCO3 electrolyte, the Faradaic efficiency for C2H4 reached 42.0% at a potential of −1.376 V vs. RHE. During continuous electrolysis over 10 h, the FE (C2H4) remained stable around 40%. During electrolysis, the fully exposed (111) crystal faces of Cu2O microcrystals are reduced to Cu0, which enhances C-C coupling and could serve as the main active sites for catalyzing the conversion of CO2 to C2H4. [ABSTRACT FROM AUTHOR]

Magnéli phase titanium suboxides (M‐TSOs) belong to a type of sub‐stoichiometric titanium oxides based on the crystal structure of rutile TiO2. They possess a unique shear structure, granting them exceptional electrical conductivity and corrosion resistance. These two advantages are crucial for electrode materials in electrochemistry, hence the significant interest from numerous researchers. However, the preparation of M‐TSOs is uneconomic due to high temperature reduction and other complex synthesis process, thus limiting their practical application in electrochemical fields. This review delves into the crystal structure, properties, and synthesis methods of M‐TSOs, and touches on their applications as electrocatalysts in wastewater treatment and electrochemical water splitting. Furthermore, it highlights the research challenges and potential future research directions in M‐TSOs. [ABSTRACT FROM AUTHOR]

Lithium‐carbon dioxide batteries (LCBs) require a thick cathode electrode to fulfill their theoretical energy density and high areal capacity (mAh cm−2). However, understanding the design of thick porous electrodes in LCBs is challenging because of the complexity of coupled multispecies transport. Herein, a link is established between the microscopic behaviors of thick electrodes and macroscopic electrochemical performance through a spatio‐temporal resolution technique, filling the gap in knowledge on the degradation mechanism of thick electrodes. Surprisingly, the worst utilization site with the least product deposition is in the central part of the electrode rather than the traditionally presumed separator face. The secondary structure and reaction pathway of solid products exhibit a clear tendency toward spatial growth (on the electrode surface or in the interior). Combined with quantitative modeling, a critical current density shifting the dominance is found from CO2 to Li+ ions, thereby reversing the gradient of the product distribution. Finally, a hotspot map of failure mechanisms with different operating protocols is provided, serving as a guideline for the future design of thick electrodes. This work breaks the knowledge of multi‐field coupling within porous thick electrodes and can be extended to advanced Na (Li)‐CO2 (O2) battery design. [ABSTRACT FROM AUTHOR]

To enrich the crystal growth strategies for the booming applications concerning lattice structure, a preferred facet‐growth method is proposed for solvothermal synthesis of target (BiO)2CO3 in the two‐phase system. The dominant crystal phase can be regulated from α‐Fe2O3 to (BiO)2CO3 by properly increasing dosage of Bi feedstock, and the optimized composite is composed of (BiO)2CO3 nanocrystal (≈10 nm) and amorphous iron oxide (defined as "FOB‐50"). Based on experimental characterizations and theoretical calculations, the highly matched lattice between (006)/(0012) facets of α‐Fe2O3 and {010} facet group of (BiO)2CO3 involving orientation of Fe─O─Fe bond and Bi─O─Bi bond is verified to facilitate the interaction between the above facets, resulting in preferred growth of {010} dominated by (040) facet in (BiO)2CO3 and its composites. The structural merits can not only enable the FOB‐50‐based electrodes to achieve a high capacity and unprecedentedly stable cyclic performances for 1500 cycles/a long time‐span of 32 months as anode materials, but also ensure the full‐cell to well inherit the electrochemical features of the cathode in potassium ion batteries (PIBs). This work can provide new insight into lattice regulation for bismuth‐based materials and expand their application as electrodes for high performance PIBs and lithium ion batteries. [ABSTRACT FROM AUTHOR]

Supercapacitors have emerged as a highly promising technology for energy storage, offering benefits such as high power output, adjustable energy density, and robust cyclic stability. The performance of these devices is largely influenced by the electrode materials used, which must provide substantial charge storage, excellent rate capability, and strong conductivity. Among various strategies developed to address these challenges, sulfurization has gained notable attention for its effectiveness in enhancing the electrochemical properties of electrode materials. This review article provides an in-depth examination of the sulfurization process applied to electrodes, aiming to deliver a thorough overview of recent advancements, the effects of sulfur integration on electrode characteristics, and the consequent improvements in supercapacitor performance. It delves into how sulfurization affects the morphology, structure, and composition of electrode materials, including changes in surface area, pore size distribution, crystal structure, and the creation of active sites. The review consolidates findings on enhanced specific capacitance, improved rate capability, extended cycle life, and increased energy density achieved through sulfurization. Additionally, it addresses the challenges and limitations of sulfurization, offering insights into potential solutions and future research directions. [Display omitted] • The cutting-edge approach, sulfurization of electrode materials is discussed. • A comprehensive analysis of the sulfurization process applied to the electrode is presented. • Explores the impact of sulfur incorporation on electrode properties. • Discovers challenges strategies to mitigate future developments. [ABSTRACT FROM AUTHOR]

Composite LaNi 0.6 Fe 0.4 O 3-δ - La 0.9 Sr 0.1 Sc 0.9 Co 0.1 O 3-δ (LNF-LSSCo) electrodes with the compositions 50/50, 60/40, and 80/20 wt% LNF/LSSCo are successfully applied for La 0.9 Sr 0.1 ScO 3-δ proton conducting electrolyte. Electrochemical activity of the electrodes is studied by impedance spectroscopy, depending on temperature and oxygen partial pressure. The best performance is observed for 60/40 LNF/LSSCo electrodes. Detailed analysis of impedance data is performed using non-linear least squares and distribution of relaxation times methods taking into account the shunt effect of electronic conductivity of La 0.9 Sr 0.1 ScO 3-δ electrolyte. Two main rate-determining stages of the electrode reaction are determined, which are assigned to oxygen ion diffusion in the bulk of the electrode and oxygen interphase exchange with the gas phase. The application of the LNF current collector layer improves the electrochemical activity of the electrodes without changes in the electrode reaction mechanism, while the modification of the electrodes with Pr 6 O 11 leads to a sufficient decrease in the resistance of the stage, corresponding to oxygen interphase exchange, resulting in a twice-improved electrochemical activity of the electrodes. [ABSTRACT FROM AUTHOR]

The reaction mechanism for the N2H4 homogeneous oxidation in aqueous solutions is more complex than its heterogeneous electrochemical oxidation on the electrode surfaces. Homogenous oxidation of a mixture of non‐labeled (14N2H4) and 15N‐labeled (15N2H4) hydrazine in aqueous solutions produces 14N15N, indicating the intermediate existence of N4H6 or N4H4 intermediates with subsequent hydrogen transfers and splitting lateral N─N bonds. To explain the key part of the hydrazine oxidation reaction, the structures, thermodynamics, and electron characteristics of N4H4 in aqueous solution are investigated. Unlike N4H6, we have not found any spontaneous splitting of the bond between the lateral nitrogens in N4H4. The most probable products of N4H4 disproportionation are H2N─NH2 and N2, which are obtained by splitting the bond between the central nitrogen atoms, and so only 15N2 and 14N2 molecules are formed. Additionally, the formation of H3N─NH and N2 products is also preferred to structures without N─N fissions. The formation of H2N═N and HN═NH is energetically less advantageous. Cyclo‐N4H4 structures are stable, without any N─N fissions, but their energies indicate their vanishing abundance in aqueous solution, so their involvement in hydrazine oxidation is highly improbable. Unlike N4H6, the oxidation of hydrazine to 14N15N molecules cannot be explained by N4H4 intermediates. [ABSTRACT FROM AUTHOR]

Activating anionic redox is an effective strategy for enhancing the capacity of cathode materials in both lithium‐ion and sodium‐ion batteries. However, the fundamental mechanisms of O3‐type sodium anionic redox cathodes remain poorly understood due to the limited availability of such materials, despite their inherent advantages such as high initial sodium content and high reversible capacity. Herein, we employ multiple characterization methods to elucidate the structural and electrochemical properties of O3‐Na[Li1/3Mn2/3]O2, a promising sodium anionic redox cathode developed recently, with a particular focus on the effect of cutoff voltages during electrochemical aging. Our synchrotron powder X‐ray diffraction results indicate that charging the material to voltages above 4.1 V induces substantial structural changes, which compromise the structural and electrochemical reversibility of the material. This is corroborated by more rapid capacity decay and increased impedance, attributed to severe degradation on both the surface and in the bulk, as evidenced by the formation of lower valence manganese compounds. Furthermore, increasing the lower cutoff voltage for the discharge process effectively suppresses surface degradation, thereby improving cycling stability. This work offers a comprehensive understanding of a pivotal sodium anionic redox cathode material, providing valuable insights that can drive the development of advanced materials for sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Sunset Yellow (SY) is an azo dye used in various food and pharmaceutical industries that deserves special attention because of its allergic and carcinogenic properties. Recently, electrochemical techniques have come to the spotlight because of their high sensitivity, simplicity and rapidity as compared to other techniques. In this work, we have developed a cost‐effective and stable electrochemical sensor by a simple method using Vitamin B12‐derived cobalt oxide coupled with g‐C3N4 (V12‐CoO/gCN) modified Au electrode. The composite prepared for the sensor was characterized using techniques such as FTIR, Powder XRD, SEM analysis, EDAX, and mapping. For electrochemical sensing of the dye Sunset Yellow, CV, DPV, and LSV techniques have been used, out of which DPV shows a better detection limit of 1.39 nM followed by LSV and CV that displayed detection limits of 3.3 nM and 4.14 nM respectively. When 5 real samples obtained from the local market are analyzed using the DPV technique, the detection limit is obtained in the range between 2.1 nM and 6.9 nM. This method leads to the development of an electrochemical sensor for the detection of Sunset Yellow to get a lower detection limit that can be used in food toxicology and related fields. [ABSTRACT FROM AUTHOR]

The binder plays a crucial role in binding the solid electrode components and fixing them to the current collector, ensuring good contact and transformation. The high‐energy‐density cathode poses several challenges for the Polyvinylidene fluoride (PVDF) binder, such as high electrode potential, mass loading, and binding force. Although various new binders are proposed to optimize the electrochemical performance of cathode, the design focus and mechanisms often lack universality. This study introduces a design strategy for the cathode binder from the perspective of molecular structure design. The performance of the binder is optimized by adjusting the soft‐hard and hydrophilic‐hydrophobic balances of the polymer, and the effectiveness of this strategy is verified in the LiCoO2 (LCO) system. The optimized copolymer binder improves the cycling stability of the LCO electrode under high load and low binder content conditions and even achieves stable operation at a high charging voltage of 4.6 V. The mechanism for improving the performance of LCO electrodes is that the optimized binder stabilizes the electrode structure, the active material particle structure, and the active material interface. This design strategy provides a valuable reference for customizing cathode binders. [ABSTRACT FROM AUTHOR]

We regulate the particle size and crystallographic facet of single-crystal (SC) Li(Ni,Mn) 2 O 4 (LNMO) cathode materials via flux-selective molten salt method. By simply adjusting Li 2 MoO 4 or LiI as sintering aids, we synthesized size controlled SC particles, both small and large, and comparatively investigated their electrochemical behavior focusing on the lithiation/delithiation reactivity in conjunction with the particle size and surface planes. Considering the growth mechanism of a SC particles with a specific crystal plane, such particle size control is not determined solely by the synthetic condition but must also consider the interfacial energy of the crystal planes in conjunction with the fluxes what we used. While the initial charge capacity is similar, the given cathode using a small SC LNMO (using LiI) with uniform particle sizes (≤5 μm) exhibits outstanding rate capability with stable capacity retention under changing current density, which indicates stable lithium transport during the repetitive electrochemical reactions. The dependency of the impedance response with change in the electrode resistances as well as the stability during the cycle reactions in conjunction with the post-mortem Li distribution by using laser-induced breakdown spectroscopy as a function of porosity change and cell degradation are thoroughly discussed from the standpoint of regulated particle property. [ABSTRACT FROM AUTHOR]

As solid‐state batteries (SSBs) emerge as leading contenders for next‐generation energy storage, chemo‐mechanical challenges and instabilities at solid‐solid interfaces remain a critical bottleneck. Ensuring sufficient interfacial contact within composite cathode architectures often requires the application of high stack pressures, posing a significant hurdle in the development of viable, large‐scale SSBs. In this work, the impact of stack pressure is investigated on the performance of solid‐state composite cathodes comprised of single‐crystal LiNi0.5Mn0.3Co0.2O2 (SC‐NMC532) active material particles and a Li6PS5Cl (LPSCl) solid electrolyte phase. By unraveling the complex interplay between stack pressure and microstructure‐dependent mechanisms, the profound influence on interfacial resistances, cathode utilization dynamics, current constriction effects, and lithiation heterogeneities are revealed. Through a comprehensive examination of coupled reaction kinetics and transport interactions at the electrode and particle length scales, the implications of stack pressure at different C‐rates and microstructural arrangements are elucidated, thereby delineating the limiting mechanisms that are prevalent at low stack pressures. This work underscores the critical role of optimizing the cathode microstructure to mitigate the chemo‐mechanical challenges associated with SSB operation at low stack pressures, offering valuable insights and design guidelines for the development of high‐performance SSBs. [ABSTRACT FROM AUTHOR]

Combining Li‐metal anodes (LMAs) with high‐voltage Ni‐rich layered‐oxide cathodes is a promising approach to realizing high‐energy‐density Li secondary batteries. However, these systems experience severe capacity decay due to structural degradation of high‐voltage cathodes and side reactions of electrolyte solutions with both electrodes. Herein, the use of multi‐functional additives in fluoroethylene carbonate‐based electrolyte solutions that enable the operation of successfully rechargeable high‐voltage (4.5 V) Li‐metal batteries (LMBs) with high areal capacity (>4 mAh cm−2) are reported. Customized electrolyte solutions are pivotal in passivating the electrodes, minimizing microcrack formation, and ensuring that current is uniformly distributed within cathode particles. The developed electrolyte solution protects the LMA by forming a very stable and effective solid–electrolyte interphase. Together with the Li[Ni0.78Co0.1Mn0.12]O2 cathode material, which is composed of radially aligned rod‐shaped primary particles, the developed high‐voltage LMB containing 20 mg cm−2 of cathode material delivers a high specific capacity of 230 mAh g−1 at 0.1 C and retains >86% of its initial capacity after 200 cycles at 0.5 C. This study highlights the significance of controlling the interfacial structure via electrolyte solution modification and the use of cathode materials with engineered morphologies that enhance mechanical stability. [ABSTRACT FROM AUTHOR]

High‐performance and temperature‐resistant lithium‐ion batteries (LIBs), which are able to operate at elevated temperatures (i.e., >60 °C) are highly demanded in various fields, especially in military or aerospace exploration. However, their applications were largely impeded by the poor electrochemical performance and unsatisfying safety issues, which were induced by the severe side reactions between electrolytes and electrodes at high temperatures. Herein, with the synergetic effects of solvation chemistry and functional additive in the elaborately designed weakly solvating electrolyte, a unique robust organic/inorganic hetero‐interphase, composed of gradient F, B‐rich inorganic components and homogeneously distributed Si‐rich organic components, was successfully constructed on both cathodes and anodes, which would effectively inhibit the constant decomposition of electrolytes and dissolution of transition metal ions, thus highly enhancing the high‐temperature electrochemical performance. As a result, both cathodes and anodes, without compromising their low‐temperature performance, can operate at temperatures ≥100 °C, with excellent capacity retentions of 96.1 % after 500 cycles and 93.5 % after ≥200 cycles, respectively, at 80 °C. Ah‐level LiCoO2||graphite full cells with a cut‐off voltage of 4.3 V also exhibited superior temperature‐resistance with a capacity retention of 89.9 % at temperature as high as 120 °C. Moreover, the fully charged pouch cells exhibited highly enhanced safety, demonstrating their potentials in practical applications at ultrahigh temperatures. [ABSTRACT FROM AUTHOR]

Owing to the synergistic effect between two metals and a high oxidation state, β-ZnMoO4 shows a high theoretical specific capacity and acts as one active material for the design and construction of lithium-ion batteries. In this paper, β-ZnMoO4 structures were formed by one hydrothermal process and characterized with XRD, SEM, Raman and XPS. The electrochemical performance tests demonstrate their excellent lithium storage capacity and cycling stability. At a current density of 2.0 A g−1, the reversible capacities of two formed β-ZnMoO4 microstructures were maintained at 665.5 and 704.6 mA h g−1 after 500 cycles. These characteristics prove that β-ZnMoO4 structures show interesting application prospects in portable energy storage devices. [ABSTRACT FROM AUTHOR]

Commercialization of solid oxide fuel cell (SOFC) is restricted due to long term performance degradation. SOFC is activated by diffusion of gasses through porous electrodes to the electrochemical active sites termed as triple phase boundary (TPB). Among all other parameters, tortuosity influences the functionality of TPB and is responsible for gas transport which relates its bulk diffusion and its migration through the porous electrode. The novelty of present research lies in designing of optimum tortuous gas diffusion path for effective hydrogen oxidation reaction through engineered morphology of anode functional layer. The study involves the fabrication of anode for planar SOFC using four configurations. Configuration A and B involves anode monolith synthesized through conventional route [(40 vol % Ni in dispersed-8 mol % Yttria stabilized zirconia (SZ)] and functional core-shell Ni@SZ. Configuration C (trilayer anode, TLA) is designed to have graded matrix with conventional Ni-SZ (fuel inlet side), 28 vol% Ni@SZ acting as active layer and 32 vol % Ni@SZ sandwiched in between. Configuration D consists of Ni@SZ as the active layer onto conventional Ni-SZ support. TLA is found to have minimum tortuosity (τ = 2) with maximum cell endurance for 2000 h (2.06–8.2 %/1000 h@800 °C under load). Ni@SZ with unimodal pore distribution is capable of reducing the activation barrier for charge migration (14 kJmol-1) compared to Ni-SZ (32 kJmol-1) with multimodal pores. This results in higher redox tolerance for Configuration B-D (4–7 % conductivity degradation/20 cycles) compared to Configuration A (27% conductivity degradation/20 cycles). Post mortem analyses of microstructure support the retention of core-shell morphology of Ni@SZ with lower deterioration. [Display omitted] • Optimization of electrochemical anodic reaction through unique microstructure of Ni-YSZ. • Tortuosity is established as the primary descriptor to control fuel TPB. • Tri-layer Ni-YSZ shows minimum tortuosity (τ=2), degradation (39 mΩ-cm2kh−1@0.5 A.cm−2,800 C. • TLA composed of conventional anode as support & Ni@SZ (electrochemical active layer). • HOR established as non-equilibrium till propagation & diffuses to equilibrium (saturation). [ABSTRACT FROM AUTHOR]

All-solid-state batteries (ASSBs) with adequately selected cathode materials exhibit a higher energy density and better safety than conventional lithium-ion batteries (LIBs). Ni-rich layered cathodes are benchmark materials for traditional LIBs owing to their high energy density. Recent studies have highlighted the advantages of using crack-free, single-crystalline cathode materials in ASSBs. In this study, a scalable infiltration sheet-type process was used to fabricate composite electrodes with different cathode-material morphologies for ASSBs. Typically, crack-free single-crystalline materials exhibit better retention performance and lower rate capability (i.e., slower kinetics in charge‒discharge processes) than polycrystalline cathode materials. Li6PS5Cl-infiltrated polycrystalline electrodes showed excellent retention performance and rate capability. Galvanostatic intermittent titration technique analysis and transmission electron microscopy of the single-crystalline electrode confirmed severe polarization and the presence of a rock-salt-structure layer in the cathode particles; these results indicated side reactions within the layered structure of the material. In contrast, composite electrodes consisting of polycrystalline cathode materials infiltrated with the solid electrolyte Li6PS5Cl showed excellent electrochemical performance owing to intimate electrode–electrolyte interfacial contact. The result from this study confirmed the critical influence of interface engineering and material morphology on the overall performance and stability of ASSBs and could facilitate the development of high-performance ASSBs in the future. This study introduces a technique for utilizing conventional lithium-ion battery electrodes in all-solid-state batteries. By infiltrating a solid electrolyte solution into the porous electrode, the effects based on the morphology of the active material were investigated. In poly-crystalline materials, high coverage and the formation of a thin side reaction layer were observed. Consequently, the infiltration process also confirmed the superior performance of poly-crystalline materials. [ABSTRACT FROM AUTHOR]

Stainless steel mesh (SSM) has emerged as a cornerstone in electrochemical applications owing to its exemplary versatility, electrical conductivity, mechanical robustness, and corrosion resistance. This state‐of‐the‐art review delves into the diverse roles of SSM across a spectrum of electrochemical domains, including energy conversion and storage devices, water treatment technologies, electrochemical sensors, and catalysis. We meticulously explore its deployment in supercapacitors, batteries, and fuel cells, highlighting its utility as a current collector, electrode, and separator. The review further discusses the critical significance of SSM in water treatment processes, emphasizing its efficacy in supporting membranes and facilitating electrocoagulation, as well as its novel uses in electrochemical sensing and catalysis, which include electrosynthesis and bioelectrochemistry. Each section delineates the recent advancements, identifies the inherent challenges, and suggests future directions for leveraging SSM in electrochemical technologies. This comprehensive review showcases the current state of knowledge and articulates the novel integration of SSM with emerging materials and technologies, thereby establishing a new paradigm for sustainable and efficient electrochemical applications. Through critical analysis and insightful recommendations, this review positions itself as a seminal contribution, paving the way for researchers and practitioners to harness the full potential of SSM in advancing the electrochemistry frontiers. [ABSTRACT FROM AUTHOR]