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Proton exchange membrane fuel cells (PEMFCs) are expected to play a pivotal role in decarbonizing the transportation sector, and particularly heavy-duty vehicles (HDVs). However, improvements in durability are needed for PEMFCs to compete with state-of-the-art power sources for HDVs. Here, we examine how catalyst layer (CL) cracks that are engineered affect the CL durability by using patterned silicon templates to control the CL crack density at the micrometer scale. Electrochemical analyses show that the initial PEMFC performance is relatively unaffected by crack density, but the performance after durability testing was strongly affected. Specifically, CLs with high crack density showed higher performance relative to CLs without cracks after application of a carbon corrosion accelerated stress test. Electrochemical analyses coupled with X-ray computed tomography and scanning transmission electron microscopy with energy dispersive X-ray spectroscopy showed that the cracks provide shorter oxygen diffusion pathways to reaction sites, leading to decreased oxygen transport resistance. Additionally, we observed that the catalyst durability is unaffected by cracks. Our results provide a mechanistic explanation of the role of cracks in CL durability.

Energy is an essential factor in many activities. The need to generate adequate energy from various sources is becoming increasingly crucial to meeting the rising needs of the world's population. Nevertheless, energy storage plays a vital role in meeting the energy demand, notably since affordable yet eco-friendly sources should meet it. Several recommendations were provided to overcome this limitation, with an increasing emphasis on energy sources. However, ecologically sustainable, and effective energy storage systems are the primary focus. Carbonaceous substances produced by pyrolyzing biomass, such as biochar, have recently gained attention as a sustainable material with the potential to be used in electrochemical energy storage technologies. It is an attractive option for electrode materials in supercapacitors, batteries, and hydrogen storage devices due to its abundant availability and distinct physicochemical characteristics, which include, excellent electric conductivity, tuneable surface functional groups, a densely porous structure, a high surface area, porosity, chemical stability, and pore volume. This review addresses the electrochemical performance, production, and characterization of materials based on biochar for energy storage developments. It investigates the choice of feedstock, various preparation routes, various controlling parameters for producing biochar, the biochar activation process, and post-treatment techniques that affect the electrochemical and structural characteristics of biochar for energy storage device fabrication in detail. Additionally, it reveals that recent developments in biochar modification methods like doping, activation, and hybridization have improved the material's capacity for energy storage. Furthermore, an in-depth discussion on the environmental impacts of biochar-based energy storage devices is elaborated, along with the opportunities and challenges presented in this study. [ABSTRACT FROM AUTHOR]

Electrodes, which offer sites for mass transfer and redox reactions, play a crucial role in determining the energy efficiencies and power densities of redox flow batteries. This review focuses on various approaches to enhancing electrode performance, particularly the methods of surface etching and catalyst deposition, as well as some other advanced strategies for regulating electrode surface properties. These approaches aim to increase active sites and enhance kinetics for the redox reactions, which are crucial for elevating power density and electrolyte utilization, eventually determining the performance of the flow battery. Highlighting the need for interdisciplinary research, this mini‐review suggests that future advancements in electrode design will significantly impact the commercial viability and adoption of redox flow batteries in sustainable energy storage solutions. [ABSTRACT FROM AUTHOR]

The current global warming, coupled with the growing demand for energy in our daily lives, necessitates the development of more efficient and reliable energy storage devices. Lithium batteries (LBs) are at the forefront of emerging power sources addressing these challenges. Recent studies have shown that integrating hexagonal boron nitride (h‐BN) nanomaterials into LBs enhances the safety, longevity, and electrochemical performance of all LB components, including electrodes, electrolytes, and separators, thereby suggesting their potential value in advancing eco‐friendly energy solutions. This review provides an overview of the most recent applications of h‐BN nanomaterials in LBs. It begins with an informative introduction to h‐BN nanomaterials and their relevant properties in the context of LB applications. Subsequently, it addresses the challenges posed by h‐BN and discusses existing strategies to overcome these limitations, offering valuable insights into the potential of BN nanomaterials. The review then proceeds to outline the functions of h‐BN in LB components, emphasizing the molecular‐level mechanisms responsible for performance improvements. Finally, the review concludes by presenting the current challenges and prospects of integrating h‐BN nanomaterials into battery research. [ABSTRACT FROM AUTHOR]

Piezoelectric ceramics with high electro strain are widely used in actuators, sensors, and so on. Here, this work investigates the electro strain of representative piezoelectric materials, and analyzes the influence of electrode type on the electro strain of PZT41 with significant strain anomalies. It is found that the occurrence of abnormally significant strain is not affected by the electrode but caused by intrinsic defects. Therefore, the ceramic samples with and without defects tailoring in Na 0.5 Bi 0.5 TiO 3 (NBT) based and PbZr 0.52 Ti 0.48 O 3 (PZT) based systems were prepared by the solid-state reaction method, and the results show that abnormally ultrahigh electro strains occur in excessively thin samples with diploes due to defects tailoring. Through displacement configuration experiments and comprehensive analysis of polarization switching processes, it is found that the occurrence of asymmetric abnormal significant strains is caused by reversible bending deformation in excessively thin samples. This work provides new support for the emergence of ultrahigh electro strain in piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Water desalination technology has emerged as a critical area of research, particularly with the advent of more cost-effective alternatives to conventional methods, such as reverse osmosis and thermal evaporation. Given the vital importance of water for life and the scarcity of potable water for agriculture and livestock—especially in the Kingdom of Saudi Arabia—the capacitive deionization (CDI) method for removing salt from water has been highlighted as the most economical choice compared to other techniques. CDI applies a voltage difference across two porous electrodes to extract salt ions from saline water. This study will investigate water desalination using CDI, utilizing a compact DC power source under 5 volts and a standard current of 2 amperes. We will convert waste materials like sunflower seeds, peanut shells, and rice husks into activated carbon through carbonization and chemical activation to improve its pore structure. Critical parameters for desalination, including voltage, flow rate, and total dissolved solids (TDS) concentration, have been established. The initial TDS levels are set at 2000, 1500, 1000, and 500 ppm, with flow rates of 38.2, 16.8, and 9.5 mL/min across the different voltage settings of 2.5, 2, and 1.5 volts, applicable to both direct and inverse desalination methods. The efficiency at TDS concentrations of 2000, 1500, and 1000 ppm remains between 18% and 20% for up to 8 min. Our results indicate that the desalination process operates effectively at a TDS level of 750 ppm, achieving a maximum efficiency of 45% at a flow rate of 9.5 mL/min. At voltages of 2.5 V, 2 V, and 1.5 V, efficiencies at 3 min are attained with a constant flow rate of 9.5 mL/min and a TDS of 500 ppm, with the maximum desalination efficiency reaching 56%. [ABSTRACT FROM AUTHOR]

Symmetric solid oxide fuel cells (SSOFCs) are attracting much attention due to their ability to improve chemical and thermal compatibility between electrolytes and electrodes and reduce manufacturing costs. The in-situ precipitating of electrode in reduction atmosphere has been proved to be an effective strategy to improve the maximum power density of SSOFCs. Herein, we use the Li(Ni x Co 2/3-x Mn 1/3)O 2 (LNCM) serial material as the symmetrical electrodes to fabricate SSOFCs, which are operated in normal and reverse mode. In reverse operation, the LNCM is firstly reduced by hydrogen and in-situ precipitates the Ni–Co alloy and Li 2 MnO 3. The electrochemical impedance spectra (EIS) indicates that the reduced product delivers excellent oxygen reducing activity as well as promising catalytic activity toward hydrogen oxidation reaction. Thus, the SSOFCs based on LNCM symmetric electrodes present superior electrochemical performance in the reverse operation. Moreover, in the LNCM serial samples, the atomic ratio of Ni and Co at the B site is adjusted to control the contents of in-situ precipitation for further optimizing the cell performance. Using Li[Ni 1/2 Co 1/6 Mn 1/3 ]O 2 as symmetric electrodes shows outstanding performance of 923 mW cm−2 at 550 °C. This work provides a reference scheme for electrode design of SSOFCs. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs) are studied and used in various fields due to their high power density, fast charging/discharging rate, as well as long cycle life. Compared to other traditional electrode and electrolyte materials, supramolecular hydrogels have great advantages in the application of SCs due to their excellent properties. Unlike covalent bonds, supramolecular systems are assembled through dynamic reversible bonds, including host–guest interactions, ion interactions, electrostatic interactions, hydrogen bonding, coordination interactions, etc. The resulting supramolecular hydrogels show some special functions, such as stretching, compression, adhesion, self‐healing, stimulus responsiveness, etc., making them strong candidates for the next generation of energy storage devices. This paper reviews the representative progress of electrodes, electrolytes, and SCs based on supramolecular hydrogels. Besides, the properties of supramolecular hydrogels, such as conductivity, extensibility, compressibility and elasticity, self‐healing, frost resistance, adhesion, and flexibility, are also reviewed to highlight the key role of excellent properties of hydrogel materials in SCs. In addition, this article also discusses the challenges faced by current technologies, hoping to continue promoting future research in this field. [ABSTRACT FROM AUTHOR]

Carbon fiber is known for being lightweight and adaptable, making it useful for various current and future applications. However, to broaden the use of carbon fibers beyond niche applications, production costs must be lowered. A potential approach to achieving this is by using more affordable raw materials, such as lignin, which is renewable, cost-effective, and widely available compared with the materials commonly used in industry today. This study explores the impact of metal ions on the quality of carbon fiber derived from lignin, focusing on its mechanical and electrochemical properties and morphology. The effect of a specific metal ion (Ni(NO3)2·6H2O) was examined by incorporating it into the spinning solution. The carbonization stage of the fiber was conducted at temperatures of 800, 900, and 1000 °C in an inert atmosphere. Scanning electron microscopy (SEM) analysis showed no defects or damage in any of the fibers. Therefore, it was concluded that moderate concentrations of Ni2+ ions in the fibers do not influence the stabilization or carbonization processes, thus leaving the mechanical properties of the final carbon fiber unchanged. These carbon nanofibers were also tested as a sustainable alternative to the non-renewable materials used in electrodes for energy storage and conversion devices, such as supercapacitors. Electrochemical performance was assessed in a 6 M KOH solution using a two-electrode cell configuration. Galvanostatic charge–discharge tests were performed at different current densities (0.1, 0.25, 0.5, 1.0, and 2.0 A g−1). The specific capacitance of the carbon nanofibers was determined from CVA data at various scan rates: 5, 10, 20, 40, 80, and 160 mV s−1. The results indicated that at 0.1 A g−1, the capacitance reached 108 F g−1, and at a scan rate of 5 mV s−1, it was 91 F g−1. The innovation of this work lies in its use of lignin, a renewable and widely available material, to produce carbon fibers, reducing costs compared with traditional methods. Additionally, the incorporation of nickel ions enhances the electrochemical properties of the fibers for supercapacitor applications without compromising their mechanical performance. [ABSTRACT FROM AUTHOR]

The aim of this research is to develop a solar-powered device to control the bloodworm Chironomus spp. in rice fields instead of using harmful chemical pesticides. The developed control device uses clean solar energy and helps to protect the environment from pesticide pollution residuals. The developed control device generates a continuous high-voltage electrocution current under soil surface to exterminate adult bloodworms and larvae. The device is provided with a fully automated electronic control circuit, an electrocution generator, and a group of electrodes. Three factors were examined to assess the efficacy of the bloodworm control device. Four electrocution potential levels (8, 12, 16, and 20 kV) were tested. Additionally, three electrode depth levels (60, 120, and 180 mm) were examined with three operating periods (10, 20, and 30 minutes). The results show high significance bloodworm population reduction using the developed device, comparing with the chemical insecticide control treatment using Furadan (Carbofuran) 10% granular. The reduction percent in bloodworms reached 90.92% and 91.94% in adult bloodworms and larvae, respectively, at the highest levels of the tested variables. The operating costs of the device ranged from 25 to 40 USA $ ha-1, while the consumed energy ranged from 40 to 100 kW h ha-1 . The use of the solar-powered control device is effective in exterminating adult bloodworms and their larvae in a short time. So, it is recommended to use the solar-powered control device to exterminate the bloodworm in rice fields. [ABSTRACT FROM AUTHOR]

In this study, xCaO‧5Fe2O3‧(95−x)Pb glasses and vitroceramics containing various concentrations of calcium ions (from 0 to 50 mol% CaO) were prepared using the spent anodic plate of a car battery. X-ray diffraction analysis revealed changes in the network structure as a function of CaO content. The intensities of the IR bands due to the sulfate and sulfite units were lowered, indicating a decrease in the sulfurization degree within the lead network. In the UV–vis spectra, the presence of electronic transitions of the Fe3+, Pb2+, and Fe2+ ions were identified. The EPR spectra were characterized by resonance signals centered at about g ~ 2 and 4.3, corresponding to the trivalent iron ions. For the samples with 5 ≤ x ≤ 12, the signals decreased abruptly, suggesting a Fe3+→Fe2+ interconversion and the formation of the Fe3O4 crystalline phase. A considerable increase in the intensity of the signal centered around g ~ 2 was observed as the CaO concentration increased to 30% in the host matrix. Our results confirm that the higher CaO levels of 3 mol% are responsible for the increase in the radius of curvature of the semicircle arcs in the EIS plots and the decrease in their conductivity. [ABSTRACT FROM AUTHOR]

In this study, we examine the combination of flexible textiles and electrodes to develop electronic textiles (e-textiles). We present a facile fabrication process using printing and coating conductive electrodes. Innovative textiles, which have evolved primarily through the integration of textile and electronic elements, have developed into e-textiles capable of performing high-dimensional tasks. For practical use of e-textiles, however, they should be compatible with various textiles, economical production, and suitable for mass production. In this study, silver ink-carbon nanotubes are used to screen-print electrodes, a key element of e-textile. We verify four types of spandex textiles and analyze whether ink-based electrodes are stably printed on the textile surfaces. As a post-process, 3D printing mold coating is invited to invent durable and water-repellent electrodes. The fabricated e-textile proves its practicality using a washing test. Additionally, electrical measurements under mechanical bending reveal a variety of potential applications based on their properties. As a result, the electrodes of e-textile have an initial electrical resistance of approximately 10 Ω. Polymer coating enhances the reliability of e-textiles. Washing tests and repeated bending deformation demonstrate that they help the coating maintain its electrical conductivity. On the other hand, electrodes without coating lose their electrical capabilities. This study proposes functional materials and reliable manufacturing methods that are beneficial for e-textile production. Accordingly, we present the diversification and potential of the smart textile industry, such as IoT sportswear, medical healthcare clothing, hazardous work detection clothing, and space exploration clothing, which are examples of applications based on e-textile materials and manufacturing technology. [ABSTRACT FROM AUTHOR]

Objective was to simulate the intravertebral placement of a novel multitined expandable electrode in bipolar configuration at the targeted ablation site and determine if the proper trajectories could be achieved in order for the device tips to be in the correct position for lesion formation at the BVN plexus. Successful device deployment required that the distance between tips was between 10 mm and 20 mm. Results: The mean distances between device tips ranged from 11.35 mm (L5) to 11.87 mm (L3), and there were no statistically significance differences across the six vertebral levels (F = 0.72, p = 0.61). The percentage of successful intraosseous device placements within the tip distance acceptable range (≥ 10 mm to ≤ 20 mm) was 90% (162 of 180), with no tip-to-tip distances > 20 mm. There was a notable association between decreasing vertebral level and mean degree of angulation between contralateral devices ranging from 50.90° at L1 to 91.51° at S1, and the difference between across the six vertebral levels was significant (F = 89.5, p < 0.01). Conclusion: Feasibility evidence is provided from real world CT imaging data that validates using the multitined electrode for proper intraosseous placement within the vertebral body to effectively ablate the BVN plexus. [ABSTRACT FROM AUTHOR]

The titanium electrode was polarized under the influence of alternating current (AC) at 50 Hz. The current density was varied between 100 and 5,000 A m−2. Initially, the titanium electrode oxidized, and then, titanium oxides were reduced during the cathodic half-cycle of the AC. When the cathodic half-cycle changes to the anodic half-cycle, titanium is oxidized to the trivalent state: Ti−3ē→ Ti3+{{\rm{Ti}}-3{\rm{e}}{\rm{̄}}\to {\rm{Ti}}}^{3+}. The direction of the AC changes depending on its frequency, causing the processes occurring on the electrodes to be periodically repeated. The current efficiency of the titanium electrode dissolution depends on the sulfuric acid concentration and electrolyte concentration, reaching up to 63.4% under optimal conditions. Bipolar electrodes were used during AC electrolysis. It was found that the decrease in the mass of titanium electrodes increases almost linearly at first, from 400 to 1,600 A m−2, and then more intensively within the current densities from 1,800 to 2,500 A m−2. It was shown that when using a bipolar electrode, the total mass loss of the electrodes is 1.38 times greater than the total mass loss during polarization without a bipolar electrode. The composition of the titanium dioxide obtained as a result of electrolysis was identified using physico-chemical analysis methods.

Abstract Characteristics of electrograms depend on the electrode design and distance to the electric source. Our aim was to assess the impact of electrode design and distance from the myocardial electric source on the unipolar and bipolar electrograms to deduce a far-field cut-off. We retrospectively analyzed left atrial electroanatomical maps of 25 patients acquired using an ablation catheter with a 4.5 mm tip-, mini- and 2 mm ring electrodes. The unipolar and bipolar electrograms were characterized based on peak-to-peak amplitude, signal duration, maximal slope, and relative power of the high frequency spectrum above 50 Hz (HF_rel). The unipolar electrograms of ring electrodes showed an increased amplitude (140%), slope (150%) and HF_rel (16% vs. 11%) compared to the tip- and mini-electrodes. The median amplitude, slope, and HF_rel for the ring electrodes followed a power-law decay with distance with a steep decline up to 4 mm. This near-field cut-off can be identified based on a HF_rel above 10% in unipolar electrograms. In conclusion, we observed a higher unipolar amplitude for small ring-electrodes compared to larger tip-electrodes. The rapid decay of the amplitude, slope, and HF_rel up to a distance of 4 mm is suggestive for near-field cut-off identified based on HF_rel above 50 Hz. Clinical Trial Registration: NCT04095559.

Goal: Transcutaneous coupling scheme for wireless powering and signal in active implants are known for more than a decade. This study aimed to investigate the in vivo behavior of this approach to drive multiple channels of an implanted peripheral nerve interfaces. Methods: The stimulation signals were transmitted through the skin over two contacts to an intracorporeal counterpart which was connected to a cuff electrode with two channels. EMG after stimulation was measured to establish recruitment curves. Results: Limitations of transcutaneous coupling were found in the feasible complexity of the system. High electrical crosstalk in a multi-channel system reduces this approach to low channel applications, such as pain treatment. No significant influence of the pulse width or extracorporeal stimulation amplitude on the electrical crosstalk was observed. Conclusions: The study's findings provide insight into the behavior of the transcutaneous coupling scheme in vivo and highlight the limitations and areas of application. Our results indicate that transcutaneous coupling schemes are a promising alternative approach for wireless powering of implants, as it does not require complex implanted electronics, expensive sophisticated electronics, and hermetic enclosures. Physical constraints, however, limit the use in highly selective nerve stimulation scenarios.

[Display omitted] Heteroatom-doped electrodes offer promising applications for enhancing the longevity and efficiency of vanadium redox flow battery (VRFB). Herein, we controllably synthesized N, P co-doped graphite fiber electrodes with conductive network structure by introducing protonic acid and combining electrodeposition and high temperature carbonization. H 2 SO 4 and H 3 PO 4 act as auxiliary and dopant, respectively. The synergistic effect between N and P introduces additional defect structures and active sites on the electrodes, thereby enhancing the reaction rate, as confirmed by density functional theory calculations. Furthermore, the conductive network structure of carbon fibers improves electrode-to-electrode connectivity and reduces internal battery resistance. The optimized integration of these strategies enhances VRFB performance significantly. Consequently, the N, P co-doped carbon fiber modified graphite felt electrodes demonstrate remarkably high energy efficiency at 200 mA cm−2, surpassing that of the blank battery by 7.9 %. This integrated approach to in-situ controllable synthesis provides innovative insights for developing high-performance, stable electrodes, thereby contributing to advancements in the field of energy storage. [ABSTRACT FROM AUTHOR]

Energy storage technologies play a crucial role in addressing the intermittent characteristics of renewable energy sources, improving the stability of electrical grids, and decreasing the release of greenhouse gas emissions. In this study, we presented nickel indium oxalate (Ni 1-x In x C 2 O 4) as a promising material with potential applications in the field of electrochemical energy storage. The as-prepared Ni-In- oxalate sample was subjected to different physical characterizations, including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Regarding the electrochemical energy storage capability, the Ni 1-x In x C 2 O 4 electrode material exhibited a specific capacitance of 835 F g−1 (417.5 C g−1) at 1 A g−1. The incorporation of nickel (Ni) into the indium (In) oxalate nanoplates enhances their electrochemical performance. The presence of Ni in the nanoplates generated from substrate, improving the overall conductivity of the material and enhances its electrochemical reactions, thus leading to improved energy storage capabilities. [ABSTRACT FROM AUTHOR]

The article describes experience of practical application of the differential thermoelectric tester "THERMO FITNESS TESTING". Description of the sensor design and results of differential thermoelectromotive force measurement for a large group of metals widely used in Russia are given. Usage of the "THERMO FITNESS TESTING" device to test the quality of R6M5 steel heat treatment is described. Dependence of thermoelectromotive force on the heating temperature which can be used for practical purposes was obtained. Usage the "THERMO FITNESS TESTING" to measure the thickness of a cemented (carburized) layer of 12KH2N4А steel is considered. Dependence of the thermoelectromotive force on the thickness of the cementation layer was also obtained.

There are various methods for cell growth monitoring. However, most of these methods have drawbacks, such as being invasive, not providing real-time results, or being costly. In this study, we present an alternate method of cell growth monitoring, which is low-cost, non-invasive, real-time, and uses Electrical Impedance Spectro-scopy (EIS). In this work, commercially available culture plates were fitted with custom tetrapolar electrodes, and mouse cells were cultured on them. The variation of culture media impedance, resulting from cell growth, proliferation and other metabolic activities, was recorded over a period of seven days. The results demonstrated an initial increase in impedance corresponding with the cell growth phase, followed by a decrease during the cell death (apoptosis) phase, as confirmed by microscope images. Overall, the results show that our method to monitor cell growth using tetrapolar electrodes is promising and can be further refined for related applications.

Abstract In this study, composite electrodes with metal–organic framework (MOF) for brackish water desalination via capacitive deionization (CDI) were developed. The electrodes contained activated carbon (AC), polyvinylidene fluoride (PVDF), and zinc-benzene tricarboxylic acid (Zn-BTC) MOF in varying proportions, improving their electrochemical performance. Among them, the E4 electrode with 6% Zn-BTC MOF exhibited the best performance in terms of CV and EIS analyses, with a specific capacity of 88 F g−1 and low ion charge transfer resistance of 4.9 Ω. The E4 electrode showed a 46.7% increase in specific capacitance compared to the E1 electrode, which did not include the MOF. Physicochemical analyses, including XRD, FTIR, FESEM, BET, EDS, elemental mapping, and contact angle measurements, verified the superior properties of the E4 electrode compared to E1, showcasing successful MOF synthesis, desirable pore size, elemental and particle-size distribution of materials, and the superior hydrophilicity enhancement. By evaluating salt removal capacity (SRC) in various setups using an initially 100.0 mg L−1 NaCl feed solution, the asymmetric arrangement of E1 and E4 electrodes outperformed symmetric arrangements, achieving a 21.1% increase in SRC to 6.3 mg g−1. This study demonstrates the potential of MOF-incorporated electrodes for efficient CDI desalination processes.

Recently, the challenges pertaining to the recycling of metal-based electrode materials and the resulting environmental pollution have impeded the advancement of battery technology. Consequently, biomass-derived carbon materials, distinguished by their eco-friendliness and consistent performance, stand as a pivotal solution to this predicament. Researchers have made significant strides in the integration of porous carbon materials derived from biomass into battery systems. Nevertheless, these materials face issues such as limited efficiency, modest yields, and a complex fabrication process. This paper endeavors to summarize the recent advancements in the utilization of biomass-derived carbon materials within the realm of batteries, offering a comprehensive examination of their battery performance from three distinct perspectives: synthesis, structure, and application. We posit that composite materials composed of biomass-derived carbon align with the trajectory of future development and present extensive potential for application. Ultimately, we will expound upon our profound outlook regarding the furtherance of biomass-derived carbon materials.

Cable bacteria are filamentous bacteria that couple the oxidation of sulfide in sediments to the reduction of oxygen via long-distance electron transport over centimeter distances through periplasmic wires. However, the capability of cable bacteria to perform extracellular electron transfer to acceptors, such as electrodes, has remained elusive. In this study, we demonstrate that living cable bacteria actively move toward electrodes in different bioelectrochemical systems. Carbon felt and carbon fiber electrodes poised at +200 mV attracted live cable bacteria from the sediment. When the applied potential was switched off, cable bacteria retracted from the electrode. qPCR and scanning electron microscopy corroborated this finding and revealed cable bacteria in higher abundance present on the electrode surface compared with unpoised controls. These experiments raise new possibilities to study metabolism of cable bacteria and cultivate them in bioelectrochemical devices for bioelectronic applications, such as biosensing and bioremediation. [ABSTRACT FROM AUTHOR]

The brain–computer interface (BCI) is one of the most powerful tools in neuroscience and generally includes a recording system, a processor system, and a stimulation system. Optogenetics has the advantages of bidirectional regulation, high spatiotemporal resolution, and cell-specific regulation, which expands the application scenarios of BCIs. In recent years, optogenetic BCIs have become widely used in the lab with the development of materials and software. The systems were designed to be more integrated, lightweight, biocompatible, and power efficient, as were the wireless transmission and chip-level embedded BCIs. The software is also constantly improving, with better real-time performance and accuracy and lower power consumption. On the other hand, as a cutting-edge technology spanning multidisciplinary fields including molecular biology, neuroscience, material engineering, and information processing, optogenetic BCIs have great application potential in neural decoding, enhancing brain function, and treating neural diseases. Here, we review the development and application of optogenetic BCIs. In the future, combined with other functional imaging techniques such as near-infrared spectroscopy (fNIRS) and functional magnetic resonance imaging (fMRI), optogenetic BCIs can modulate the function of specific circuits, facilitate neurological rehabilitation, assist perception, establish a brain-to-brain interface, and be applied in wider application scenarios. [ABSTRACT FROM AUTHOR]

Wire electrochemical micromachining has good technical advantages in the processing of metal material microdevices. However, because it is a special material containing insoluble solid particles, 40CrNiMoA exhibits poor processing stability, frequent ignition, and serious electrode wear. In this study, an attempt was made to promote mass transfer, reduce or even avoid abnormal discharge, and reduce electrode loss using solution ultrasonic assistance. The experimental results show the following. First, the thickness of the workpiece has a great influence on the process stability, and it is difficult to stably process 2-mm workpieces without ultrasonic assistance. Second, increasing the voltage to 32 V to increase the slit width causes stronger discharge to occur because of the increase of products and particles. Third, ultrasound assistance can improve the interelectrode flow field, promoting the smooth progress of the reaction and protecting the electrode. Fourth, the electrode rotation speed can be increased to enhance the medium exchange, but the electrode loss increases because of the decrease in electrolysis ability. Finally, a square spiral structure (with an overall length of 31 mm) was processed stably by optimizing the parameters. [ABSTRACT FROM AUTHOR]

This very study presented an innovative Co3(PO4)2@Mn₃(PO4)2@Ni3(PO4)2 enhanced using Vitex doniana leaf extract for supercapacitor electrodes application fabricated through chemical bath deposition method to achieve distinct crystalline phases and unique spherical-like and flaky-like structures integrated into nickel (Ni) foam substrate. The synergistic effect between Co3O4, MnO2, and NiO enhances the general superficial area, porosity, and conductivity of the fabricated electrodes toward improving the overall supercapacitor performance. The comprehensive electrochemical analysis performed confirmed the electrode's excellent properties engaging cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD), indicating elevated specific capacitance, an enhanced rate capability, and elongated stability, using potassium hydroxide (KOH) engaged as the electrolyte during the study. The incorporation of Vitex doniana leaf extract additionally heightened the performances, demonstrating huge prospects for an innovative energy storage application. The fabricated supercapacitor electrodes exhibited outstanding energy and power densities, making them promising candidates for practical applications in supercapacitor devices. A broad analysis of the electrochemical impedance spectroscopy (EIS) presented an understanding of charge transfer rates and the effects of using Vitex doniana leaf extract. This work contributed to the understanding of the synergistic effects of composites of transition metallic oxides and leaf extracts on advancing the high performance of supercapacitors. [ABSTRACT FROM AUTHOR]

A novel NiO/MnO2 pompon-like hybrid structure was synthesized through a facile one-step hydrothermal in situ growth approach in this paper. NiO nanosheets grow on MnO2 pompon-like microsphere to form typical hybrid structures which significantly increase the abundant active sites of electrode materials. The resulting NiO/MnO2 electrode material exhibits an impressive specific capacity of 2706.1 F/g at a current density of 1 A/g. Remarkably, NiO/MnO2 pompon-like hybrid structure shows excellent cycling performance and its capacity retention is maintained at 84.8% and the charge–discharge efficiency at 96% after 15,000 cycles. Even after undergoing 40,000 cycles, the electrode material maintains an outstanding charge–discharge efficiency of 95.2% with capacity retention of 69%, which revealing promising application as long-term electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Microbial electrochemical systems that integrate the advantages of inorganic electrocatalysis and microbial catalysis are expected to provide sustainable solutions to the increasing energy shortages, resource depletion, and climate degradation. However, sluggish extracellular electron transfer (EET) at the interface between electroactive microorganisms and inorganic electrode materials is a critical bottleneck that limits the performance of systems. Electrocatalytic nanomaterials are highly competitive in overcoming this obstacle due to their effective association with microbial catalysis. Therefore, this review focuses on the cutting-edge applications and enhancement mechanisms of nanomaterials with electrocatalytic activity in promoting microbial EET. First, the EET mechanism of microbial electrocatalysis in both microbial anodes and cathodes is briefly introduced, and then recent applications of various electrocatalytic nanomaterials in diverse microbial electrochemical systems are summarized, including heteroatom-doped carbons and precious metal, as well as transition metal oxides, sulfides, carbides, and nitrides. The synergistic effects of nanomaterial electrocatalysis and microbial catalysis on enhancing interfacial EET are analyzed. Finally, the challenges and perspectives of realizing high-performance microbial electrochemical systems are also discussed in order to offer some reference for further research. [ABSTRACT FROM AUTHOR]

Objective:Gasserian ganglion stimulation (GGS) is a neuromodulation technique that has been extensively applied in treating postherpetic trigeminal neuralgia. However, permanent implantation of GGS was preferred in most treatment approaches. Few studies have investigated temporary GGS for the treatment of acute/subacute herpetic trigeminal neuralgia. Moreover, previous research has reported lead dislocation when utilizing traditional electrodes, which was associated with poor pain relief. In GGS research, preventing the accidental displacement of lead following implantation has consistently been a primary objective. Methods: We report a case of a 70-year-old woman with subacute herpetic trigeminal neuralgia who underwent temporary GGS for 14 days utilizing a sacral neuromodulation (SNM) quadripolar-tined lead. Computed tomography-guided percutaneous foramen ovale (FO) puncture and temporary SNM electrode implantation were performed during the surgery. A telephone interview was conducted to record a 12-month follow-up. Results: At admission, zoster-related trigeminal pain severity was assessed to be 9/10 on the visual analog scale (VAS). After a 14-day GGS treatment, the pain assessed on the VAS score reduced to 1/10 at discharge but increased to 4/10 at the 12-month follow-up after surgery. Additionally, the anxiety level improved from 58 points to 35 points on the Self-Rating Anxiety Scale (SAS), and the depression level improved from 62 points to 40 points on the Self-Rating Depression Scale (SDS). The Physical Component Summary score of the 12-item Short-Form Health Survey (SF-12) increased from 33.9 to 47.0, and the Mental Component Summary (MCS) score of the SF-12 increased from 27.4 to 41.9. Conclusion: Temporary GGS might be a potentially effective treatment for subacute herpetic trigeminal neuralgia, and an SNM electrode might be a good choice for reducing the risk of dislocation. [ABSTRACT FROM AUTHOR]

Electroactive microfiber-based scaffolds aid neural tissue repair. Carbon microfibers (CMFs) coated with the conducting polymer poly(3,4-ethylenedioxythiophene) doped with poly[(4-styrenesulfonic acid)-co-(maleic acid)] (PEDOT:PSS-co-MA) provide efficient support and guidance to regrowing axons across spinal cord lesions in rodents and pigs. We investigated the electrical and structural performance of PEDOT:PSS-co-MA-coated carbon MFs (PCMFs) for long-term, biphasic electrical stimulation (ES). Chronopotentiometry and electrochemical impedance spectroscopy (EIS) allowed the characterization of charge transfer in PCMFs during ES in vitro, and morphological changes were assessed by scanning electron microscopy (SEM). PCMFs that were 4 mm long withstood two-million-biphasic pulses without reaching cytotoxic voltages, with a 6 mm length producing optimal results. Although EIS and SEM unveiled some polymer deterioration in the 6 mm PCMFs, no significant changes in voltage excursions appeared. For the preliminary testing of the electrical performance of PCMFs in vivo, we used 12 mm long, 20-microfiber assemblies interconnected by metallic microwires. PCMFs-assemblies were implanted in two spinal cord-injured pigs and submitted to ES for 10 days. A cobalt–alloy interconnected assembly showed safe voltages for about 1.5 million-pulses and was electrically functional at 1-month post-implantation, suggesting its suitability for sub-chronic ES, as likely required for spinal cord repair. However, improving polymer adhesion to the carbon substrate is still needed to use PCMFs for prolonged ES. [ABSTRACT FROM AUTHOR]

The galvanic dissolved oxygen sensor finds widespread applications in multiple critical fields due to its high precision and excellent stability. As its core sensing components, the oxygen-permeable membrane, electrode, and electrolyte significantly impact the sensor's performance. To systematically investigate the comprehensive effects of these core sensing components on the performance of galvanic dissolved oxygen sensors, this study selected six types of oxygen-permeable membranes made from two materials (Perfluoroalkoxy Polymer (PFA) and Fluorinated Ethylene Propylene Copolymer (FEP)) with three thicknesses (0.015 mm, 0.03 mm, and 0.05 mm). Additionally, five concentrations of KCl electrolyte were configured, and four different proportions of lead–tin alloy electrodes were chosen. Single-factor and crossover experiments were conducted using the OxyGuard dissolved oxygen sensor as the experimental platform. The experimental results indicate that under the same membrane thickness conditions, PFA membranes provide a higher output voltage compared to FEP membranes. Moreover, the oxygen permeability of FEP membranes is more significantly affected by temperature. Furthermore, the oxygen permeability of the membrane is inversely proportional to its thickness; the thinner the membrane, the better the oxygen permeability, resulting in a corresponding increase in sensor output voltage. When the membrane thickness is reduced from 0.05 mm to 0.015 mm, the sensor output voltage for PFA and FEP membranes increases by 86% and 74.91%, respectively. However, this study also observed that excessively thin membranes might compromise measurement accuracy. In a saturated, dissolved oxygen environment, the sensor output voltage corresponding to the six oxygen-permeable membranes used in the experiment exhibits a highly linear inverse relationship with temperature (correlation coefficient ≥ 98%). Meanwhile, the lead–tin ratio of the electrode and electrolyte concentration have a relatively minor impact on the sensor output voltage, demonstrating good stability at different temperatures (coefficient of variation ≤ 0.78%). In terms of response time, it is directly proportional to the thickness of the oxygen-permeable membrane, especially for PFA membranes. When the thickness increases from 0.015 mm to 0.05 mm, the response time extends by up to 2033.33%. In contrast, the electrode material and electrolyte concentration have a less significant effect on response time. To further validate the practical value of the experimental results, the best-performing combination of core sensing components from the experiments was selected to construct a new dissolved oxygen sensor. A performance comparison test was conducted between this new sensor and the OxyGuard dissolved oxygen sensor. The results showed that both sensors had the same response time (49 s). However, in an anaerobic environment, the OxyGuard sensor demonstrated slightly higher accuracy by 2.44%. This study not only provides a deep analysis of the combined effects of oxygen-permeable membranes, electrodes, and electrolytes on the performance of galvanic dissolved oxygen sensors but also offers scientific evidence and practical guidance for optimizing sensor design. [ABSTRACT FROM AUTHOR]

The large water demand, insufficient deposition on the back of the leaf and the uneven distribution of droplets are the problems of traditional agricultural ground plant protection machinery, which leads to low agricultural control efficiency. Combined with the advantages of electrostatic spray technology and the characteristics of high working efficiency and low probability of droplets drift of ground sprayer, an inductive electrostatic boom spray system based on embedded electrode structure is designed and mounted on a large self-propelled boom sprayer for field testing. Based on the working characteristics of the fan nozzle and the analysis of the theory of charge, the inductive electrostatic spray device is designed. The performance of the device is tested and the rationality of the system design is verified by COMSOL numerical simulations, charge-to-mass ratio, and particle size distribution measurements. The spray deposition scanning software and the BoxBehnken experimental design method are used to analyze the spray droplet deposition rate and coverage density of the sprayer on the front and back of the target leaves. The results show that the embedded closed electrode structure designed in this paper can avoid the problem of electrode wetting, and the electric field generated by it is mainly concentrated in the spray liquid film area, and the intensity reaches 6~7 V/m. At the conventional application height (500 mm), the maximum charge-to-mass ratio is 2.91 mC/kg, and the average particle size is 168.22 mm, which is 12.87% lower than that of ordinary spray, when the spray pressure is 0.3 MPa and the electrostatic voltage is 12 kV. The results of field experiments show that the optimum combination of the working parameters with the spray speed is 8.40 m/s, the spray pressure is 0.35 MPa, the charging voltage is 11.50 kV, the amount of droplet deposition in the lower dorsal area of the blade is 1.44 µL·cm-2. This study can provide a certain basis for the application of electrostatic spray technology in ground sprayers. [ABSTRACT FROM AUTHOR]

Traumatic peripheral nerve injuries (PNI), present with symptoms ranging from pain to loss of motor and sensory function. Difficulties in intraoperative visual assessment of nerve functional status necessitate intraoperative nerve conduction studies (INCSs) by neurosurgeons and neurologists to determine the presence of functioning axons in the zone of a PNI. This process, also referred to as nerve "inching", uses a set of stimulating and recording electrode hooks to lift the injured nerve from the surrounding surgical field and to determine whether an electrical stimulus can travel through the zone of injury. However, confounding electrical signal artifacts can arise from the current workflow and electrode design, particularly from the mandatory lifting of the nerve, complicating the definitive assessment of nerve function and neurosurgical treatment decision-making. The objective of this study is to describe the design process and verification testing of our group's newly designed stimulating and recording electrodes that do not require the lifting or displacement of the injured nerve during INCSs. Ergonomic in vivo analysis of the device within a porcine model demonstrated successful intraoperative manipulation of the device, while quantitative nerve action potential (NAP) signal analysis with an ex vivo simulated "inching" procedure on healthy non-human primate nerve tissue demonstrated excellent reproducible recorded NAP fidelity and the absence of NAP signal artifacts at all points of recording. Lastly, electrode pullout force testing determined maximum forces of 0.43 N, 1.57 N, and 3.61 N required to remove the device from 2 mm, 5 mm, and 1 cm nerve models, respectively, which are well within established thresholds for nerve safety. These results suggest that these new electrodes can safely and successfully perform accurate PNI assessment without the presence of artifacts, with the potential to improve the INCS standard of care while remaining compatible with currently used neurosurgical technology, infrastructure, and clinical workflows. [ABSTRACT FROM AUTHOR]

The nonlinear characteristics of avalanche photodiodes (APDs) inhibit their performance in high-speed communication systems, thereby limiting their widespread application as optical detectors. Existing theoretical models have not fully elucidated complex phenomena encountered in actual device structures. In this study, actual APD structures exhibiting lower linearity than their ideal counterparts were revealed. Simulation analysis and physical inference based on GaN APDs reveal that electrode size is a noteworthy factor influencing response linearity. This discovery expands the nonlinear theory of APDs, suggesting that APD linearity can be enhanced by suppressing the electrode size effect. A physical model was developed to explain this phenomenon, which is attributed to charge accumulation at the edge of the contact layer. Therefore, we proposed an improved APD design that incorporates an additional gap layer and a buffer layer to stabilize the internal gain under high-current-density conditions, thereby enhancing linearity. Our improved APD design increases the linear threshold for optical input power by 4.46 times. This study not only refines the theoretical model for APD linearity but also opens new pathways for improving the linearity of high-speed optoelectronic detectors. [ABSTRACT FROM AUTHOR]

Ionic liquid modification for carbon-supported platinum (Pt/C) electrocatalysts to enhance their oxygen reduction reaction (ORR) activity has been well recognized. However, the research has only been reported on the low-Pt-loading Pt/C electrocatalysts, e.g., 20 wt%, while in practical applications, usually high-Pt-loading Pt/C electrocatalysts of 45–60 wt% are used. In this work, ionic liquid modification is systematically investigated for a Pt/C electrocatalyst with 60 wt% Pt loading for its ORR activity in the cathode in proton exchange membrane fuel cells (PEMFCs). Various adsorption amounts are studied on the catalyst surface. Different modification behavior is found. Mechanism exploration shows that the adsorption of ionic liquid mainly happens on the Pt electrocatalyst surface and in the micropores of the carbon support. The highest fuel cell power performance is achieved at an ionic liquid loading of 7 wt%, which is much higher than the 3 wt% reported for the low-Pt-loading Pt/C. [ABSTRACT FROM AUTHOR]

The development of electrically conductive polymer-based filament is the challenging process in energy storage applications. Moreover, the development of electrodes using polymer-based conductive material is fascinating researchers mainly for lithium-ion battery. In this work, electrical film casting was prepared using CMC/SBR and PLA pellets with Graphite elements. The anode was developed with active, conductive, and binder materials of PLA, Graphite, and SBR/CMC materials respectively. The fixed active and conductive elements were taken with different range (0-50%) of binder for preparing anode using the slurry film process. Totally six specimens were made with different binder compositions in the dimensions of ~50 mm diameter and ~5 mm thickness. The mechanical and electrochemical characteristics were analyzed to investigate cell voltage, microstructure, composition analysis, electrical and thermal conductivity with the influence of binder composition. A binder composition of 20-30% was completely formed in the good conductive path. Moreover, the electrical conduction path formed by the binder elements in PLA matrix reached the percolation threshold at this range. Binder with 30% was determined as the best ratio of plasticizer to be added with PLA/Graphite matrix to minimize porous structure and to make well defined bonding of active, conductive and binder elements. Therefore, a maximum Shore D value of 25.4 and tensile strength of ~27 MPa were noted on the specimen casted with 30% of binder elements. The results of Half-cells galvanostatically characteristics revealed that 30% of CMC/SBR can be obtained a high specific discharge capacity of 238 (mAh/g). The FEA analysis exhibited that the maximum cell voltage of 3 V-4.6 V during charging and 4.3 V-3 V during discharging at 0.5C rate for the specimen prepared with 30 wt% binder. [ABSTRACT FROM AUTHOR]

Polyaniline has been utilized in various applications, yet its widespread adoption has often been impeded by challenges. Composite systems have been proposed as a means of mitigating some of these limitations, and anthranilic acid (2-aminobenzoic acid) has emerged as a possible moderator for use in co-polymer systems. It offers improved solubility and retention of electroactivity in neutral and alkaline media, and, significantly, it can also bestow chemical functionality through its carboxylic acid substituent, which can greatly ease post-polymer modification. The benefits of using anthranilic acid (as a homopolymer or copolymer) have been demonstrated in applications including corrosion protection, memory devices, photovoltaics, and biosensors. Moreover, this polymer has been used as a versatile framework for the sequestration of metal ions for water treatment, and, critically, these same mechanisms serve as a facile route for the production of catalytic metallic nanoparticles. However, the widespread adoption of polyanthranilic acid has been limited, and the aim of the present narrative review is to revisit the early promise of anthranilic acid and assess its potential future use within modern smart materials. A critical evaluation of its properties is presented, and its versatility as both a monomer and a polymer across a spectrum of applications is highlighted. [ABSTRACT FROM AUTHOR]

This review paper presents a comprehensive analysis of the electrode materials used for Li-ion batteries. Key electrode materials for Li-ion batteries have been explored and the associated challenges and advancements have been discussed. Through an extensive literature review, the current state of research and future developments related to Li-ion battery electrodes were identified. The study also covers a wide range of subtopics, including the theoretical aspects of the basic functioning of lithium-ion batteries and the crystal structures of different electrode materials. Additionally, emerging trends and future directions in the development of high-performance commercial battery electrodes have been revealed, providing insights into promising avenues for further research. By synthesizing existing knowledge and analyzing the latest research, this review aims to provide a valuable resource for researchers, practitioners, and stakeholders interested in developing state-of-the-art high-performance Li-ion batteries. The findings and perspectives presented in this paper contribute to a deeper understanding of electrode materials for Li-ion batteries and their advantages and disadvantages, ultimately fostering advancements and innovations in commercial lithium-ion battery (LiB) electrode technology. [ABSTRACT FROM AUTHOR]

Exploring the method for rational design of hierarchical structures such as hollow, sphere, and core–shell structures is a crucial challenge for enhancing the electrochemical performance of supercapacitor electrodes. In this study, we demonstrate a facile method for controllable preparation of hydrangea-shaped CoAl-LDHs/CoF2 composite and used as a positive electrode for supercapacitor. A series of contrast tests are performed to select optimal experiment condition. CoAl-LDHs obtained at a metal ratio of 2:1, reacting 8 h with the addition of NH4F, display optimal performance associated with the hierarchical structure, where NH4F plays a vital role in regulating this uniform generation process. The fabricated working electrode shows a high specific capacitance of 827.8 Fg−1, with excellent capacitance retention of 62.8% after current density increases ten times. At last, an asymmetric supercapacitor using C2A1-8 h sample as positive electrode and activated carbon as negative electrode is assembled and delivers an outstanding energy density of 53.7 Wh kg−1 at a power density of 239.9 kW kg−1, and energy density reaches 27.8 Wh kg−1 at maximum power density of 12,000 W kg−1, indicating C2A1-8 h is a potential candidate for energy storage and conversion systems. [ABSTRACT FROM AUTHOR]

Transparent organic light-emitting diodes (OLEDs) have the advantages of excellent visual experience and low power consumption, and can be applied to flexible display technology, completely breaking from traditional display technology. Transparent conductive electrodes (TCEs) are an important component for realizing high-performance OLEDs. At present, cathode materials widely used in transparent OLEDs include Mg:Ag alloys and Ca:Ag alloys; however, their low transmittance makes the light extraction rate relatively low. In this study, a composite transparent conductive cathode with a ZnO/Ca:Au/Al2O3 structure was fabricated by atomic layer deposition (ALD), achieving excellent optical transmittance, mechanical flexibility, and lateral conductivity. The ZnO layer prepared by ALD was used as the seed layer of the ultrathin Ca:Au alloy layer, while ensuring the low work function of the entire structure, and the Al2O3 layer prepared by ALD was used as an anti-reflection layer and encapsulation layer to improve the optical transmittance and the overall structure of the device lifetime. The luminance and external quantum efficiency (EQE) of the transparent OLED prepared in this work were significantly improved over the traditional Ca:Ag electrode, achieving values of 40,000 cd/m2 and 31.2% at 5 V, respectively, and the average transmittance of the device in the visible light range was 53%. [ABSTRACT FROM AUTHOR]

Growing populations and development led to a higher utilization of fossil fuels and more CO2 emissions; which prompted researchers to look for pollution-free energy sources and improved energy-storage technologies. Supercapacitors (SCs) are thought to be the most advanced available energy-storage technology and are improving day by day via modifying the electrode composition. In this work, we described the hydrothermal production of SrCeO3/RGO nanocomposite as an effective and high-performance electrode material for SCs. Different approaches were adopted to look at the structural features along with the electrochemical behaviors of the prepared nanocomposite. X-ray structural analysis data and surface analysis showed that the nanocomposite had a pure crystalline phase and enhanced surface area. SrCeO3/RGO nanocomposite possessed a specific capacitance of 1359.9 F/g at 1 A/g, while it was 653.1 F/g for pure SrCeO3 electrode. The nanocomposite showed a small decrease in its polarization curve area following the 6000th cycle of the stability test. Additionally, SrCeO3 and SrCeO3/RGO nanocomposite exhibited specific energy of 28.7 and 63.5 Wh/kg at 1 A/g value with specific power of 281.5 and 290.1 W/kg, respectively. Numerous findings demonstrated that the enhanced ion/electron mobility and electric conductivity of nanocomposite lead to a rapid charge-storing approach and significantly boost electrochemical performance. The exceptional functionality of the SrCeO3/RGO nanocomposite demonstrated its favorable potential for the future generation of energy storage by reducing reliance on materials with a spinel-like structure. Highlights: SrCeO3/RGO nanocomposite prepared via hydrothermal route and was utilized as supercapacitor electrode. Exhibited exceptional morphological features evaluated through various physical characterizations. GCD results showed an enhanced rate capability of 1359.9 F/g at 1 A/g. Impedance results exhibited enhanced electrical features than their pristine materials. [ABSTRACT FROM AUTHOR]

Abstract Electrodes, which offer sites for mass transfer and redox reactions, play a crucial role in determining the energy efficiencies and power densities of redox flow batteries. This review focuses on various approaches to enhancing electrode performance, particularly the methods of surface etching and catalyst deposition, as well as some other advanced strategies for regulating electrode surface properties. These approaches aim to increase active sites and enhance kinetics for the redox reactions, which are crucial for elevating power density and electrolyte utilization, eventually determining the performance of the flow battery. Highlighting the need for interdisciplinary research, this mini‐review suggests that future advancements in electrode design will significantly impact the commercial viability and adoption of redox flow batteries in sustainable energy storage solutions.

Energy is an essential factor in many activities. The need to generate adequate energy from various sources is becoming increasingly crucial to meeting the rising needs of the world’s population. Nevertheless, energy storage plays a vital role in meeting the energy demand, notably since affordable yet eco-friendly sources should meet it. Several recommendations were provided to overcome this limitation, with an increasing emphasis on energy sources. However, ecologically sustainable, and effective energy storage systems are the primary focus. Carbonaceous substances produced by pyrolyzing biomass, such as biochar, have recently gained attention as a sustainable material with the potential to be used in electrochemical energy storage technologies. It is an attractive option for electrode materials in supercapacitors, batteries, and hydrogen storage devices due to its abundant availability and distinct physicochemical characteristics, which include, excellent electric conductivity, tuneable surface functional groups, a densely porous structure, a high surface area, porosity, chemical stability, and pore volume. This review addresses the electrochemical performance, production, and characterization of materials based on biochar for energy storage developments. It investigates the choice of feedstock, various preparation routes, various controlling parameters for producing biochar, the biochar activation process, and post-treatment techniques that affect the electrochemical and structural characteristics of biochar for energy storage device fabrication in detail. Additionally, it reveals that recent developments in biochar modification methods like doping, activation, and hybridization have improved the material’s capacity for energy storage. Furthermore, an in-depth discussion on the environmental impacts of biochar-based energy storage devices is elaborated, along with the opportunities and challenges presented in this study.

Abstract Supercapacitors (SCs) are studied and used in various fields due to their high power density, fast charging/discharging rate, as well as long cycle life. Compared to other traditional electrode and electrolyte materials, supramolecular hydrogels have great advantages in the application of SCs due to their excellent properties. Unlike covalent bonds, supramolecular systems are assembled through dynamic reversible bonds, including host–guest interactions, ion interactions, electrostatic interactions, hydrogen bonding, coordination interactions, etc. The resulting supramolecular hydrogels show some special functions, such as stretching, compression, adhesion, self‐healing, stimulus responsiveness, etc., making them strong candidates for the next generation of energy storage devices. This paper reviews the representative progress of electrodes, electrolytes, and SCs based on supramolecular hydrogels. Besides, the properties of supramolecular hydrogels, such as conductivity, extensibility, compressibility and elasticity, self‐healing, frost resistance, adhesion, and flexibility, are also reviewed to highlight the key role of excellent properties of hydrogel materials in SCs. In addition, this article also discusses the challenges faced by current technologies, hoping to continue promoting future research in this field.

ZnO nanoparticles were used as composites on carbon paste working electrodes to enhance electrode performance in the analysis of nicotine content in e-cigarette liquids by voltammetry cyclic. The optimum composition and condition (pH and scan rate) were determined to identify the conditions that gave the best response. ZnO nanoparticles were synthesized using the sol-gel method and characterized by FTIR, XRD, and SEM. The determination of optimum composition and conditions was studied using cyclic voltammetry. The determination of nicotine content in e-cigarette liquids was analyzed by cyclic voltammetry. The electrode composition that gave the best response was 3:5:2 (carbon: nanoparticles ZnO: paraffin). The optimum conditions for nicotine determination by cyclic voltammetry were at pH 8 and a scan rate of 90 mVs-1. The cyclic voltammetry’s limit detection (LoD) using a ZnO nanoparticles-modified carbon paste electrode is 0.00678 mg/mL, and the percent recovery is 100.35%.

The escalating demand for green hydrogen (H2) as a sustainable energy carrier has attracted intensive research into efficient water electrolysis methods. Promising candidates have emerged as binder-less metal electrodes, which enhance electrochemical performance and durability by reducing electron hindrance and avoiding binder degradation. Despite their potential, a comprehensive understanding of various binder-less fabrication techniques remains limited in the existing literature. As the main objective, this review paper aims to bridge this gap by providing an in-depth analysis of state-of-the-art fabrication methods for binder-less metal electrodes utilized in electrochemical water splitting. Recognizing the critical need for sustainable hydrogen production, the advantages of binder-less electrodes over conventional binder-based counterparts are elucidated, with emphasis placed on their role in promoting cost-effectiveness, improved stability, and enhanced catalytic activity. Techniques such as Hydrothermal/Solvothermal, Electrodeposition, Chemical/Vapor Deposition, and Laser-based fabrication are systematically examined, with their respective advantages, drawbacks, and comparison being highlighted. Drawing upon relevant examples from literature, insights on other aspects and recent trends are also provided, such as the performance of binder-less metal electrodes at industrial-scale current densities (0.1–1 A/cm2) or their potential as photoactive catalysts. Additionally, future directions in the field of binder-less electrode fabrication and the exploration of innovative techniques are also discussed, ensuring that the trajectory of research aligns with the evolving demands of sustainable energy production. The ''what's next'' section highlights areas of further investigation and potential avenues for technological advancement.

Geleneksel fosil yakıtlar, rezervlerinin sınırlı ve ciddi zararlı kirletici sorunlarının olması önemli problemdir. Fosil yakıtlara en önemli sürdürülebilir alternatif yakıt ve enerji kaynağı hidrojendir. Hidrojenin kimyasal enerjisinin elektrik enerjisine dönüştürüldüğü sistem olan direkt hidrojenli PEM yakıt hücresi umut vaat eden bir enerji kaynağıdır. Bu çalışmada PEM yakıt hücresinin bileşenlerinin ve bazı durumların PEM yakıt hücresi performansına etkisi irdelenmiştir. Öncelikle PEM yakıt hücresinin çalışma sistemi irdelendi. Yakıt hücresinin parçaları ve bu parçaların yakıt hücresi yığın maliyetine etkisi incelendi. Son olarak membran, gaz difüzyon tabakası, bipolar tabaka ve anot-katot elektrotlarının PEM yakıt hücresi performansına etkileri araştırıldı. PEM yakıt hücresinde membran kalınlığı azaldıkça performansının arttığı görüldü. Gaz difüzyon tabakasında az veya aşırı suyun, yakıt hücresi performansı sınırlayıcı etkisi tespit edildi. Grafit gibi elektrik iletkenliği iyi olan ve korozyona dayanıklı bipolar plakanın yakıt hücresi performansını artırdığı tespit edildi. Elektrotların elektrik iletkenliği ve hidrojenin elektrotların yüzeyine tutunma kabiliyeti artıkça performansı olumlu etkilediği görüldü.

This study aims to investigate the impact of varying the mass ratio of Ni to Graphene Nano Sheets (GNS) and how incorporating GNS affects the performance of a primary battery prototype (Ni/GNS//electrolyte//GNS). The primary battery prototype was developed using both impregnation and alloy methods. Different mass ratios of Ni/GNS to electrolyte to GNS were tested, including ratios of 1:2:1 (A), 2:2:1 (B), 1:2:2 (C), 2:1:2 (D), and 1:1:2 (E). The characterization of GNS, Ni/GNS, and the primary battery prototype involved using X-Ray Diffraction (XRD) and Scanning Electron Microscope-Energy Dispersive X-Ray (SEM-EDX) instruments. A multimeter was employed to measure electrical conductivity, energy density, and power density. A potentiostat/galvanostat was used to measure cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). XRD analysis showed a broad and weak peak at 2θ= 24.32° for GNS, confirming its successful synthesis. Additionally, a peak at 2θ = 43.5° indicated effective deposition of Ni on the GNS surface in Ni/GNS. The SEM-EDX results supported the XRD findings, showing regularly spaced pores and a thin surface layer in GNS. Notably, white spots on the graphene surface in Ni/GNS indicated successful Ni deposition. In terms of electrical conductivity, the highest value was observed in the primary battery prototype for sample D (2:1:2), which measured 1.11 S/cm2. These results were also supported by measurements of energy density and power density in sample D, which achieved the highest values among all samples, with 144,788 Wh/kg and 252,500 W/kg, respectively. Moreover, the CV and EIS measurements remained stable at 0.30 kΩ and 0.88 kΩ, suggesting that GNS could potentially conduct electrons owing to its electrical conductivity.