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Reliable and economical energy storage technologies are urgently required to ensure sustainable energy supply. Hydrogen (H2) is an energy carrier that can be produced environment-friendly by renewable power to split water (H2O) via electrochemical cells. By this way, electric energy is stored as chemical energy of H2, and the storage can be large-scale and economical. Among the electrochemical technologies for H2O electrolysis, solid oxide electrolysis cells (SOECs) operated at temperatures above 500 ℃ have the benefits of high energy conversion efficiency and economic feasibility. In addition to the H2O electrolysis, SOECs can also be employed for CO2 electrolysis and H2O–CO2 co-electrolysis to produce value-added chemicals of great economic and environmental significance. However, the SOEC technology is not yet fully ready for commercial deployment because of material limitations of the key components, such as electrolytes, air electrodes, and fuel electrodes. As is well known, the reactions in SOEC are, in principle, inverse to the reactions in solid oxide fuel cells (SOFCs). Component materials of SOECs are currently adopted from SOFC materials. However, their performance stability issues are evident, and need to be overcome by materials development in line with the unique requirements of the SOEC materials. Key topics discussed in this review include SOEC critical materials and their optimization, material degradation and its safeguards, future research directions, and commercialization challenges, from both traditional oxygen ion (O2−)-conducting SOEC (O-SOEC) and proton (H+)-conducting SOEC (H-SOEC) perspectives. It is worth to believe that H2O or/and CO2 electrolysis by SOECs provides a viable solution for future energy storage and conversion.

Silicon-based lithium-ion battery negative electrodes represent one of graphite's most promising replacements. However, the enhanced capacity and unique Li+ storage method have raised the demands on the binder and other passive electrode components. For cycle stability, a sufficient carbonaceous matrix with silicon is needed. One of the most desirable anode materials for Li-ion batteries (LIBs) is Si, which has been noted for its exceptional volumetric and gravimetric qualities. Its affordability, abundance, and environmental safety stand out in particular. We assess the most recent improvements in the production of intercalation-type, conversion-type, and alloying-type anode materials in this work. After explaining the electrochemical reaction and failure, we reviewed several techniques for enhancing battery performance, including nanostructuring, alloying, building hierarchical structures, and employing the proper binders. Researchers will get the necessary information from this research work to conduct future research.

Two-dimensional (2D) MXenes are promising materials for a variety of sustainable energy-related applications such as photoelectrochemical water splitting and energy storage devices. Among the MXene family, the Ti3C2Tx is mostly prepared by selective etching of Al from the Ti3AlC2 MAX phase using hydrofluoric acid (HF) or in-situ produced HF as an etchant. However, the severe toxicity, handling of HF acid as well as the oxidation and degradation of freshly synthesized MXenes when stored as aqueous suspensions obstruct the large-scale production of MXenes. 3D printing is an innovative and versatile technology utilized for a plethora of applications in the field of energy applications. Thus, integration of 3D printing technology with the synthesis procedure of MXene will provide a new outlook for large-scale production and the long-storing capability of MXene. Herein, we fabricated a novel MAX (Ti3AlC2)/polylactic acid (PLA) filament for fused deposition modeling (FDM) 3D printing followed by etching of the 3D-printed MAX/PLA electrode into 3DP-etched-MAX employing chronoamperometry technique consecutively in 9 M HCl and 4 M NaOH as electrolytes. The 3D printed electrochemically etched MAX (3DP-etched-MAX) electrode shows promising behaviour for the photoelectrochemical hydrogen evolution reaction (HER) and capacitive performance. In general, this work demonstrates a path of production of large-scale manufacturing of MAX/PLA filament and 3DP-etched-MAX electrodes without using toxic HF for energy conversion and energy storage applications. This work paves the way to fabricate other novel MAX filaments and electrodes for several applications beyond energy conversion and storage.

Abstract Electrodes are used to measure a potential difference between two points. In geophysical and geotechnical applications they are often in the form of non‐polarizable porous‐pot electrodes. Here we describe the design, construction, and testing of modular and refillable electrodes, which facilitates repair as the electrodes degrade over time. We use a chemical composition based on a metal in contact with an over‐saturated electrolyte that consists of a salt of that metal and an auxiliary salt. We compare characteristics when the electrolyte is stabilized in a clay or not, and with various states of ceramic porous plugs and two types of wood plugs. Next, we assess the long‐term stability (more than 1 month), noise (periods of 1 s to 1 hr), and temperature sensitivity of different types of electrodes. Electrodes with an electrolyte and clay formula showed lower noise (0.2–0.4 μV at periods of 1–120 s), greater long‐term stability (0.05–0.5 mV/month of smooth drift), and greater consistency between samples measured than those with no clay (noise and drift values up to four times larger). The effects from different porous plugs were negligible, with similar results for ceramic and wood types. The temperature sensitivity of the electric potential was assessed, from −3 to 35°C. All electrodes showed a temperature sensitivity of about −30 μV/°C. This is considered very low compared to some commercially available electrodes. Finally, continuous long‐term laboratory and field measurements of the potential highlight the application of the new electrodes.

To produce the free-standing electrodes, a binder-free direct growth method was employed for electrode fabrication. A NiCo2O4@Ni-MOF (metal–organic framework) composite was synthesized using a one-pot hydrothermal method. Initially, a NiCo2O4 nanowire array was cultivated on Ni foam, serving as a connecting bridge to ensure robust adherence of the Ni-MOF to the substrate. The structures of NiCo2O4 nanowire arrays exhibit the capacity for numerous redox reactions. Hybridizing MOF with transition metal oxide (TMO) nanoarchitectures can significantly alleviate the small specific surface area and aggregation tendency of TMOs. The highest energy storage capacity was obtained when the ratio of nickel to terephthalic acid (TPA) was 4:1. NiCo2O4@Ni-MOF (Ni:[Formula: see text]:1) exhibited a high storage capacitance of 1700[Formula: see text]F/g. The integration of MOF with TMO nanoarchitectonics as materials for supercapacitor electrodes can enhance porous structure and facilitate diffusion during both charging and discharging processes.

A new device improves the way scientists can record the activity of motor units in a wide range of animals and settings.

Voltammetry has been used in many industries and has been a popular method for food analysis in recent years. Its high sensitivity, rapid analysis, usability in a wide variety of concentrations and temperatures have positive potential in the wine industry. With standardized methods for food analysis being too work-intensive and time-consuming for the fast market demand, the main purpose of this study was to gain an understanding of the possible benefits that voltammetry can provide to the wine industry. This review paper focused its discussion on the different voltammetric methods, parametric conditions, and electrochemical behavior of essential compounds from wine as the main substance of interest. In particular, the limit of detection (LOD), initial voltage peak, pH levels, working electrodes, and their respective reagents were taken into account to determine the applicable methods that can be utilized in the wine industry. This study could serve as a point of reference for future research into the topic. [ABSTRACT FROM AUTHOR]

Multilayer grid electrodes consisting of Cu0.7Ni0.3/Cu/Cu0.7Ni0.3 utilize the high conductivity of Cu to realize low electrical resistance and the high corrosion resistance of CuNi to improve reliability. The effect of thickness of outer CuNi layer on corrosion resistance and visibility was investigated. Samples prepared with 2 μ m line width on PET having grid mesh side length of 300 μ m, and 60° internal angle with 280 nm thickness showed a transmittance of 90.1% at 550 nm and sheet resistance of 2.4 Ω/□ after grid pattern formation. The low process temperature enabled electrode formation on thin substrate, 23 μ m-thick PET and accomplish highly durable and flexible electrode on PET. The superior bending properties showed no change in sheet resistance after 200 000 cycles of outer/inner fatigue bending tests at 3 mm radius of curvature. Additionally, the potential for foldable usage was further supported by demonstrating the ability to form electrodes on both sides of the film. [ABSTRACT FROM AUTHOR]

Waste wood, which has a large amount of cellulose fibers, should be transformed into useful materials for addressing environmental and resource problems. Thus, this study analyzed the application of waste wood as supercapacitor electrode material. First, cellulose fibers were extracted from waste wood and mixed with different contents of graphene nanoplatelets (GnPs) in water. Using a facile filtration method, cellulose papers with GnPs were prepared and converted into carbon papers through carbonization and then to porous activated carbon papers containing GnPs (ACP−GnP) through chemical activation processes. For the morphology of ACP−GnP, activated carbon fibers with abundant pores were formed. The increase in the amount of GnPs attached to the fiber surfaces decreased the number of pores. The Brunauer–Emmett–Teller surface areas and specific capacitance of the ACP−GnP electrodes decreased with an increase in the GnP content. However, the galvanostatic charge–discharge curves of ACPs with higher GnP contents gradually changed into triangular and linear shapes, which are associated with the capacitive performance. For example, ACP with 15 wt% GnP had a low mass transfer resistance and high charge delivery of ions, resulting in the specific capacitance value of 267 Fg−1 owing to micropore and mesopore formation during the activation of carbon paper. [ABSTRACT FROM AUTHOR]

There has been tremendous research progress among scientists in the development of hybrid solar cells (HSC) as green solar energy. The research aims to investigate the influence of several types of transparent conductive electrodes on the performance of fabricated HSC. Single-layer graphene (SG)-based film has been identified as a potential replacement for indium tin oxide (ITO)-based film as anode transparent conductive layer (ATCL) in HSC. In this work, we have fabricated ITO-based HSC (ISc), SG-based HSC (GSc), and heat-treated SG-based HSC (HGSc). It was observed that the power conversion efficiency (PCE) was significantly dependent on the types of ATCL. These significant findings are measured by Raman spectroscopy, a UV–Vis spectrophotometer, and a solar simulator. The HGSc possesses the best PCE of 1.960%, compared to 1.225% in the ISc, with an open-circuit voltage (Voc) of 0.5 V, a short-circuit photocurrent density (Jsc) of 11.2 mAcm−2, and a fill factor (FF) of 0.35. The properties of heat-treated SG-based film were significantly attributed to PCE enhancement in HSC. As a conclusion, the use of graphene-based film has opened up a new research interest in the solar cell fabrication process. [ABSTRACT FROM AUTHOR]

Fig. 3 Overview of the application of BDC materials in VRFB. [Display omitted] Biomass-derived carbon (BDC) materials are suitable as electrode or catalyst materials for vanadium redox flow battery (VRFB), owing to the characteristics of vast material sources, environmental friendliness, and multifarious structures. A timely and comprehensive review of the structure and property significantly facilitates the development of BDC materials. Here, the paper starts with the preparation of biomass materials, including carbonization and activation. It is designed to summarize the lastest developments in BDC materials of VRFB in four different structural dimensions from zero dimension (0D) to three dimension (3D). Every dimension begins with meticulously selected examples to introduce the structural characteristics of materials and then illustrates the improved performance of the VRFB due to the structure. Simultaneously, challenges, solutions, and prospects are indicated for the further development of BDC materials. Overall, this review will help researchers select excellent strategies for the fabrication of BDC materials, thereby facilitating the use of BDC materials in VRFB design. [ABSTRACT FROM AUTHOR]

Ag and AgNO film were fabricated through sputter deposition on indium tin oxide (ITO) conductive glass. Electrochemical detection using cyclic voltammetry (CV) was carried out for low albumin levels in blood as a parameter of cancer patients. This study aims to determinate low albumin level as a biomarker cancer. Albumin adsorption on the Agfilm/ITO and AgNOfilm/ITO was also investigated to determine the level of sensitivity of both electrodes. Analysis of the CV measurements indicated that the Agfilm/ITO electrode was more sensitive compared to the AgNOfilm/ITO electrode, with a sensitivity value of 4.564 µA M-1cm-2 for the Agfilm/ITO electrode and 2.123 µA M-1cm-2 for the AgNOfilm/ITO electrode. The testing of albumin levels in blood within a range of low concentration levels between 10-1 and 10-8 g/dL indicated a detection limit of 10-9 g/mL. The selectivity of Ag electrodes was found to be very good for other interfering molecules such as urine, glucose, and lysozyme. The results of the modeling of electric field and magnetic field distribution showed that the Agfilm/ITO electrode possessed larger values than the AgNOfilm/ITO electrode. From this analysis, it can be concluded that the electrode modified with micro-sized Ag achieved more effective results than the electrode modified with AgNO. This sensor can determine low albumin level as a blood cancer biomarker. This sensor holds great promise for use in real samples in the future. [ABSTRACT FROM AUTHOR]

Background and Objectives: Carbon materials bearing advantages such as chemical and thermal stability, electrical conductivity, high specific surface area, and high porosity are widely used in electrode materials. While wood-based carbon materials exhibit good capacitive behavior and offer increased charge storage capacity, their electrical conductivity is often insufficient for optimal performance as carbon electrodes. To enhance their conductivity, composite materials combining wood-based carbon with other conductive materials have been synthesized. In this study, we assessed the physicochemical and electrochemical properties of nanocomposite electrodes based on carbonized wood/Mn-MOF, which were prepared using the in-situ synthesis method. Additionally, we investigated the performance of these electrodes as cathodes in sediment microbial fuel cells. Furthermore, we compared their performance with that of control wood-based electrodes and commercially available carbon felt electrodes. Materials and Methods: The sapwood blocks of Platanus orientalis were used as a lignocellulosic precursor and subjected to pyrolysis at a temperature of 700 °C. The heating rate was set at 5 °C min-1, and the pyrolysis process took place in an argon atmosphere with a constant flow of 100 mL/min and a retention time of 1 hour. Following pyrolysis, the carbonized wood samples were washed with distilled water and subsequently dried in an oven. To synthesize composite electrodes of CW/Mn-MOF, we employed manganese (II) acetate tetrahydrate and a 1,3,5-benzene tricarboxylic acid ligand. The resulting samples were washed with ethanol and dried once more in the oven. For secondary pyrolysis, the samples were subjected to a temperature of 900 °C for a duration of 2 h in an argon atmosphere, with a heating rate of 5 °C min-1 . Results: The findings revealed that the porous structure and its interconnected and direct channels were successfully maintained after wood pyrolysis. Moreover, the in-situ synthesis of Mn-MOF on carbonized wood was achieved. Raman spectra analysis indicated an increase in the degree of disorder in the structure of the prepared nanocomposite electrodes compared to the control carbonized woods. Additionally, XRD patterns demonstrated the presence of both amorphous and graphitic carbon within the graphitic crystals of carbon. Furthermore, the carbon electrodes doped with Mn-MOF exhibited the lowest impedance and the highest maximum power density when compared to the control and carbon felt electrodes. Conclusion: It was found that high-temperature carbonization leads to the graphitization of wood material, resulting in increased electrical conductivity. The doping of carbon electrodes and the fabrication of carbon-nanocomposite electrodes using carbonized wood/Mn-MOF significantly enhanced the electrochemical performance of the cathode in sediment microbial fuel cells. The combination of the pseudocapacitive behavior of Mn-MOF and the electrical double-layer capacitance behavior of the carbon material exhibited a synergistic effect, which ultimately improved the overall performance of the SMFC setup. [ABSTRACT FROM AUTHOR]

Cochlear implantation is a major treatment option for severe-to-profound hearing loss. By insertion into the cochlea and stimulation of the cochlear nerve, cochlear implantation can improve the performance of hearing and speech performance of the implantees. The microenvironment of the cochlea is innate and gets disturbed in response to the insertion of a foreign body. However, realtime changes inside the cochlea in terms of electrophysiology at the molecular level can never be investigated in vivo in human beings. Thus, impedance is a good guide that reflects the electrophysiology inside the cochlea. Because the initial measurement of impedance cannot be performed earlier than the traditional interval of 1 month postoperatively, early changes in impedance have not been explored until recently; however, surgeons are now trying the initial switch-on earlier than 1 month after implantation. This review discusses the scenario of electrophysiological variation after early switch-on in <1 day postimplantation. Evidence has shown that fluctuations in impedance after implantation depend on the interplay between cell cover formation, fibrosis, electrode design, and electrical stimulation. Further studies addressing the correlation between impedance and clinical parameters are required to develop reliable biomarkers for better performance of cochlear implantation. [ABSTRACT FROM AUTHOR]

The measurement of biosignals in the clinical and healthcare fields is fundamental; however, conventional electrodes pose challenges such as incomplete skin contact and skin-related issues, hindering accurate biosignal measurement. To address these challenges, conductive hydrogels, which are valuable owing to their biocompatibility and flexibility, have been widely developed and explored for electrode applications. In this study, we fabricated a conductive hydrogel by mixing polyethylene glycol diacrylate (PEGDA) with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) polymers dissolved in deionized water, followed by light-triggered crosslinking. Notably, this study pioneered the use of a PEGDA−PEDOT:PSS hydrogel for electrocardiogram (ECG) monitoring- a type of biosignal. The resulting PEGDA−PEDOT:PSS hydrogel demonstrated remarkable conductivity while closely approximating the modulus of skin elasticity. Additionally, it demonstrated biocompatibility and a high signal-to-noise ratio in the waveforms. This study confirmed the exceptional suitability of the PEGDA−PEDOT:PSS hydrogel for accurate biosignal measurements with potential applications in various wearable devices designed for biosignal monitoring. [ABSTRACT FROM AUTHOR]

The horizontal flatbed electrophoresis method is employed to separate protein samples, providing greater flexibility for various electrophoretic applications and easier sample loading compared to its vertical counterpart. In the currently available equipment setup, cathode and anode electrodes are positioned on top of a gel at each end. Since an electric field enters the gel from the top, its strength gradually weakens from the top to the bottom of the gel. When examining the interior of gels following electrophoretic separation, the uneven electric field causes the protein bands to lie down forward in the direction of migration, leading to an increase in bandwidth. This issue has remained unaddressed for several decades. To address this problem, new clamp-shaped and double-deck electrodes were developed to apply an electric field simultaneously from both the top and bottom of the gel. Both of these new electrodes facilitated the formation of perpendicular protein band shapes and enhanced resolution at a comparable level. Due to their ease of use, double-deck electrodes are recommended. By combining these new electrodes with the field inversion gel electrophoresis (FIGE) technique, the protein bands could be focused and aligned nearly vertically, resulting in the highest level of electrophoretic resolution. Our electrodes are compatible with polyacrylamide gels of varying sizes, buffer systems, and sample well formats. They can be easily manufactured and seamlessly integrated into existing laboratory instruments for practical use. [ABSTRACT FROM AUTHOR]

The synthesis of two-dimensional NiO nanostructures by programmable chemical deposition in combination with the hydrothermal treatment of intermediates in distilled water and in aqueous ammonia solution was studied. Simultaneous thermal analysis was used to determine the dependence of thermal stability and sorption capacity of particles of the intermediates on the parameters of their hydrothermal treatment and on the composition of the dispersion medium. The results of IR spectroscopy and X-ray diffraction analysis helped us to recognize the crystal structure specifics and the set of functional groups for intermediates and for NiO nanopowders formed on their basis. The average size of the coherent scattering regions (CSRs) of the manufactured nickel oxide powders varied from 4.0 ± 0.5 to 8.6 ± 0.8 nm depending on the hydrothermal treatment parameters. Scanning (SEM) and transmission (TEM) electron microscopy showed that the recrystallization of NiO nanoparticles can be tuned depending on the synthesis parameters to yield two-dimensional nanostructures of various shapes and required sizes, ranging from nanosheets of chaotic geometry to flat hexagons with a variable diameter. Due to their anisotropic microstructure, the manufactured nanomaterials can be effectively used in the fabrication of functional components for advanced alternative energy devices (supercapacitor electrodes, solid oxide fuel cells, etc.), including the use of printing technologies. [ABSTRACT FROM AUTHOR]

The formation of hierarchically organized MoS2 films on various substrates by a hydrothermal method was studied. The influence of synthesis conditions and the substrate (a glass or a flexible carbon paper substrate) on the crystal structure of sulfide films was determined using X-ray powder diffraction (XRD). Scanning electron microscopy (SEM) showed that the films on glass substrates comprised structurally different elements, namely a continuous dense layer of spherical nanoparticles on the surface of which hierarchically organized globular agglomerates of two types are arranged. A molybdenum disulfide shell about 1.5 μm thick, consisting of hierarchically organized nanosheets less than 10 nm thick, was formed on the surface of carbon fibers that make up the carbon paper. Elemental mapping was used to evaluate the homogeneity of the MoS2 film formed on the carbon paper. Atomic force microscopy (AFM) showed that an individual carbon fiber modified with a sulfide film had a mean square roughness of about 13 nm (over an area of about 100 μm2). According to Kelvin-probe force microscopy (KPFM) data, the electron work function of the material was 4.53 eV. The electrochemical characteristics of the manufactured flexible electrode based on a hierarchically organized molybdenum disulfide film were investigated. The specific capacitance and the stability of functional and microstructural properties of the manufactured supercapacitor electrode in 2000 charge–discharge cycles were evaluated. Thus, the proposed strategy is promising for the fabrication of efficient hierarchically organized MoS2 electrodes for flexible supercapacitors. [ABSTRACT FROM AUTHOR]

The increasing scarcity of fresh water due to rapid population growth and the establishment of new industries every single day has motivated researchers to use efficient technologies for the removal of dissolved salts from water. Various methods of salt removal and wastewater treatment have been established in last decades; however, membrane capacitive deionization has gained much attention due to its low energy consumption and low process costs in water treatment applications. The progress of membrane capacitive deionization for desalination and water treatments is systematically presented in this review. This review includes significant input on the membrane capacitive deionization progress, the current status of membrane capacitive deionization in the removal of salts and different pollutants, and a comparative discussion on various membranes and electrodes used in membrane capacitive deionization reported so far. It also highlights a summary and future scope in the area of membrane capacitive deionization. Based on the literature available and a review of the membrane capacitive deionization process, it could be a more effective and promising process for desalination and water purification. [ABSTRACT FROM AUTHOR]

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Nanomaterials, including carbon nanotubes, graphene oxide, metal–organic frameworks, metal nanoparticles, and porous carbon, play a crucial role as efficient carriers to enhance enzyme activity through substrate channeling while improving enzyme stability and reusability. However, there are significant debates surrounding aspects such as enzyme orientation, enzyme loading, retention of enzyme activity, and immobilization techniques. Consequently, these subjects have become the focus of intensive research in the realm of multi-enzyme cascade reactions. Researchers have undertaken the challenge of creating functional in vitro multi-enzyme systems, drawing inspiration from natural multi-enzyme processes within living organisms. Substantial progress has been achieved in designing multi-step reactions that harness the synthetic capabilities of various enzymes, particularly in applications such as biomarker detection (e.g., biosensors) and the development of biofuel cells. This review provides an overview of recent developments in concurrent and sequential approaches involving two or more enzymes in sequence. It delves into the intricacies of multi-enzyme cascade reactions conducted on nanostructured electrodes, addressing both the challenges encountered and the innovative solutions devised in this field. [ABSTRACT FROM AUTHOR]

ZnS nanoparticles (NPs) are prepared by co-precipitation method using ethylene diamine tetra-acetic acid as a stabilizer and capping agent. The structural, morphological and optical properties of as-synthesized NPs are investigated using X-ray diffraction, scanning electron microscope, Fourier transform infrared spectroscopy, ultraviolet-visible (UV-Vis) absorption, and photoluminescence spectroscopy. The X-ray diffraction pattern exhibits a zinc-blended crystal structure at room temperature. The particle size was found to be in the range of 22.22 nm. The ultraviolet absorption spectrum shows the blue shift in the bandgap due to the quantum confinement effect. The photoluminescence spectrum of ZnS NPs shows a blue visible spectrum. The template of the cyclic voltammetry contour demonstrated a strong rate suggesting that the ZnS nanostructure electrode has a reduced polarization effect. The above studies have provided resplendent efficiency and proven that ZnS NPs can be used as a prominent material for supercapacitor applications. [ABSTRACT FROM AUTHOR]

The resistive switching (RS) behavior of multilayered ReRAM devices is typically influenced by two aspects: the intrinsic properties of the dielectric multilayer, and other extrinsic contributions. In this study, we deposited and investigated bi-layered memories incorporating ZnO and HfO 2 dielectrics. Different stacking sequences of the two oxides (ZnO/HfO 2 and HfO 2 /ZnO) were employed to explore the intrinsic contribution of the bilayer microstructure, while different top electrode configurations (Pt and Ti) were utilized to demonstrate the extrinsic impact. All devices exhibit characteristic bipolar RS behavior, showcasing their functionality. But interestingly, the device with a Pt top electrode displays digital RS behavior, while the one with a Ti top electrode exhibits analog RS behavior. The completely different switching types observed during the reset process of the ZnO-HfO 2 hybrid resistive memories are attributed to different interface charge migration process and structural characteristic. And as compared to the tailoring effect of stacking sequences (bilayer microstructure and oxide/oxide interface), the tailoring effect of top electrode configuration (electrode materials and oxide/electrode interface) is much stronger. Based on the latter, the switching ratio can be remarkably improved by at least two orders of magnitude, the reset voltage (energy consumption) can also be significantly reduced, and other discussed switching parameters can also show greater improvement. The comprehensive comparative analysis of intrinsic and extrinsic contributions provides valuable insights for exploring the RS mechanism and optimizing the design of bi-layered memory devices. [ABSTRACT FROM AUTHOR]

The ability and capacity of silicon and carbon nanocages (C38, F-C38, Cl-C38, Si38, F-Si38, Cl-Si38) as anodes of batteries are investigated to suggest the new nano-compounds as basic material of electrodes of batteries with suitable performance. The electrochemical parameters of C and Si nanocages as anodes of batteries are examined and compared by using of the computational models. The halogen (F and Cl) atoms are linked to Si38 and C38 as anodes in batteries to improve their capacity by theoretical models. The interaction energies of nanostructures with F and Cl atoms, interaction energies of nanostructures with Li and Mg and interaction energies of F-nanostructures and Cl-nanostructures with Li+ and Mg+2 ions are calculated by theoretical models. Finally, the F-Si38 and Cl-Si38 nanocages are suggested as suitable effective nano structures to utilize as electrodes in batteries. [ABSTRACT FROM AUTHOR]

To improve the electrochemical performance of Li‐S batteries, sulfur composites are prepared through sulfur's melt‐diffusion into porous materials such as metal organic frameworks (MOFs). MOFs are porous nanocrystalline materials consisting of metal ions and organic ligands. Due to their high porosity, specific surface area, and easily controllable porous structure, MOFs and their derivatives are considered useful materials for holding sulfur. Herein, the effect of the concentration of the reactants on the particle diameter distribution of ZIF‐67 is studied, and the performance of the product as a sulfur host for Li‐S battery cathode is evaluated. ZIF‐67 was prepared by regulating the Co2+ concentration in solution from 10 to 250 mM, with a constant mole ratio between Co2+ and the organic ligand. Cyclovoltammetry, galvanostatic charge–discharge, and rate capability tests were performed to electrochemically characterize each sample as a sulfur host for Li‐S battery cathodes. MeZ‐50 mM, prepared with 50 mM Co2+ ion solution, had the smallest particle diameter (591 nm). The sulfur cathode utilizing MeZ‐50 mM afforded the best electrochemical performance (883.7 mAh gS−1). This study demonstrates that the particle size of ZIF‐67 can be controlled by adjusting the reactant concentration, enabling manipulation of the electrochemical properties as a sulfur host. [ABSTRACT FROM AUTHOR]

The development of efficient and durable oxygen evolution reaction (OER) catalysts is of great significance for the application of high-efficiency alkaline water electrolysis hydrogen production technology. In this work, a highly efficient and stable OER catalyst with a layered structure, in which layered hydroxides of FeCoNi(OH)x are prepared on a Ni mesh substrate by electrodeposition. In three-electrode tests, the FeCoNi(OH)x/Ni mesh has an overpotential of 138 mV at 10 mA cm−2, much lower than that of Ni mesh (341 mV) and Raney Ni/Ni mesh (277 mV). Under the condition of 50 mA cm−2, FeCoNi(OH)x/Ni mesh exhibits excellent stability for 80 h. Moreover, when installed in a single cell of an alkaline electrolysis cell, the FeCoNi(OH)x/Ni mesh electrode cell voltage is 2.003 V at 8000 A m−2, much lower than the Ni mesh (2.224 V) and Raney Ni/Ni mesh (2.086 V), demonstrating excellent OER performance. Tafel slope, contact angles, and EIS tests reveal that the synthesized FeCoNi(OH)x/Ni mesh shows favorable kinetics, super hydrophilic surface, and fast bubble detachment, ultimately reducing the OER overpotential and promoting electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Electrochemical methods can be used not only for the sensitive analysis of proteins but also for deeper research into their structure, transport functions (transfer of electrons and protons), and sensing their interactions with soft and solid surfaces. Last but not least, electrochemical tools are useful for investigating the effect of an electric field on protein structure, the direct application of electrochemical methods for controlling protein function, or the micromanipulation of supramolecular protein structures. There are many experimental arrangements (modalities), from the classic configuration that works with an electrochemical cell to miniaturized electrochemical sensors and microchip platforms. The support of computational chemistry methods which appropriately complement the interpretation framework of experimental results is also important. This text describes recent directions in electrochemical methods for the determination of proteins and briefly summarizes available methodologies for the selective labeling of proteins using redox-active probes. Attention is also paid to the theoretical aspects of electron transport and the effect of an external electric field on the structure of selected proteins. Instead of providing a comprehensive overview, we aim to highlight areas of interest that have not been summarized recently, but, at the same time, represent current trends in the field. [ABSTRACT FROM AUTHOR]

Purpose: Awake craniotomy with intraoperative functional brain mapping (FBM) bedside neurological testing is an important technique used to optimize resective brain surgeries near eloquent cortex. Awake craniotomy performed with electrocorticography (ECoG) and direct electrical stimulation (DES) for FBM can delineate eloquent cortex from lesions and epileptogenic regions. However, current electrode technology demonstrates spatial limitations. Our group has developed a novel circular grid with the goal of improving spatial recording of ECoG to enhance detection of ictal and interictal activity. Methods: This retrospective study was approved by the institutional review board at Mayo Clinic Florida. We analyzed patients undergoing awake craniotomy with ECoG and DES and compared ECoG data obtained using the 22 contact circular grid to standard 6 contact strip electrode. Results: We included 144 cases of awake craniotomy with ECoG, 73 using circular grid and 71 with strip electrode. No significant differences were seen regarding preoperative clinical and demographic data, duration of ECoG recording (p = 0.676) and use of DES (p = 0.926). Circular grid was more sensitive in detecting periodic focal epileptiform discharges (PFEDs) (p = 0.004), PFEDs plus (p = 0.032), afterdischarges (ADs) per case (p = 0.022) at lower minimum (p = 0.012) and maximum (p < 0.0012) intensity stimulation, and seizures (p = 0.048). PFEDs (p < 0.001), PFEDs plus (p < 0.001), and HFOs (p < 0.001) but not ADs (p = 0.255) predicted electrographic seizures. Conclusion: We demonstrate higher sensitivity in detecting ictal and interictal activity on ECoG during awake craniotomy with a novel circular grid compared to strip electrode, likely due to better spatial sampling during ECoG. We also found association between PFEDs and intraoperative seizures. [ABSTRACT FROM AUTHOR]