Electrode Arrangement Research Articles

Laser exfoliated 2D MXene for supercapacitor applications

MXenes-based compounds, particularly Ti3C2Tx, have been studied intensively as electrodes for supercapacitors due to their layered structure and high conductivity, enabling facile ion diffusion and charge transfer. However, tight restacking of the 2D layers in these materials limits their practical, accessible surface area, thereby impeding their capacity and rate capability performance. To mitigate this phenomenon, we present a new approach using a processing method based on laser beam irradiation to modify Ti3C2Tx films. We found that the laser treatment induces chemical and morphological changes, ultimately optimizing the stacking arrangement of the MXene electrodes and consequently enhancing their capacity in both neutral and acidic electrolytes. Furthermore, the laser-modified MXene electrodes demonstrate excellent rate capabilities, showing 84 % retention at extreme rates of 0.5 V compared to only 33 % of the original Ti3C2Tx electrodes. Finally, we discuss the chemical and physical changes induced by the laser treatments and their influence on the electrochemical behavior of the lasered MXene. The principles of laser exfoliation discovered in this study can be implemented in broader 2D materials for various applications.

Effect of Electrode Positioning on Electrokinetic Remediation of Contaminated Soft Clay with Surface Electrolyte.

Soft clay contamination is an increasingly global issue with significant implications for land development and human health. Electrokinetic remediation (EKR) has demonstrated significant potential for cleaning contaminated soils. It is crucial to develop efficient processes that minimize environmental impact and reduce costs. A series of citric acid (CA)-enhanced EKR tests were conducted using a novel experimental setup, with the electrolyte positioned above the soil surface, to examine the impact of four different electrode arrangements on the effectiveness of EKR. The position of the electrode end had a significant impact on the migration of ions in the anolyte and catholyte, which in turn affected the volume reduction in the anolyte, the magnitude of the current, and the migration of heavy metals. The electrode arrangement mode c (electrodes suspended in the electrolytes) can enhance the migration of the anolyte and reduce the drainage of the soil, making it an effective measure for improving the removal rate of heavy metals. After the heavy metal remediation is complete, the bearing capacity of the soil should be increased. Changing the electrode arrangement to mode d (anode suspended in the anolyte, a very small part of the cathode inserted into the soil) is an effective measure for reducing the soil water content and improving soil strength.

Triangular electrode arrangement for minimizing electrode density and footprint in tactile sensors and flexible electronics

Triangular electrode arrangement for minimizing electrode density and footprint in tactile sensors and flexible electronics

Influence of the radiofrequency applicators arrangement on the sizes of ablative zones inside hepatic tumor

Radiofrequency (RF) ablation is a popular therapeutic technique for heating solid tumors that are medically unsuitable for resection or other treatments. Thermal ablation applicators create high-frequency electromagnetic fields (EMFs) within the tumor site, which causes heating, coagulation, and ultimately death of the cancer cells. The aim of this study is the numerical analysis of the temperature distributions, ablation zones, and specific absorption rates (SAR) during RF ablation in relation to an ellipsoidal shaped tumor placed in the model of liver tissue. The source of heat is a three-element system of RF needle applicators operating at a frequency 100 kHz, with a given electrode potential, inserted into the tumor. In order to obtain an appropriate temperature distribution in the target area, the Laplace equation coupled with the Pennes equation were solved using the finite element method (FEM). The arrangement effect of three needle-type applicators on the resultant thermal profiles and the volumes of ablation zones were analyzed and compared. In addition, the ablation zones for various angles of the RF applicator placed in the center of the tumor were analyzed. The paper shows that in order to control temperature distribution and ablation zones the proposed system of RF applicators and the arrangement of electrodes can be successfully applied in hepatocellular carcinoma treatment.

A method for quantitative spatial analysis of immunolabeled fibers at regenerative electrode interfaces

BackgroundRegenerative electrodes are being explored as robust peripheral nerve interfaces for neuro-prosthetic control and sensory feedback. Current designs differ in electrode number, spatial arrangement, and porosity which impacts the regeneration, activation, and spatial distribution of fibers at the device interface. Knowledge of sensory and motor fiber distributions are important in optimizing selective fiber activation and recording. New MethodWe use confocal microscopy and immunofluorescence methods to conduct spatial analysis of immunolabeled fibers across whole nerve cross sections. ResultsThis protocol was implemented to characterize motor fiber distribution within 3 macro-sieve electrode regenerated (MSE), 3 silicone-conduit regenerated, and 3 unmanipulated control rodent sciatic nerves. Total motor fiber counts were 1485 [SD: +/- 50.11], 1899 [SD: +/- 359], and 5732 [SD: +/- 1410] for control, MSE, and conduit nerves respectively. MSE motor fiber distributions exhibited evidence of deviation from complete spatial randomness and evidence of dispersion and clustering tendencies at varying scales. Notably, MSE motor fibers exhibited clustering within the central portion of the cross section, whereas conduit regenerated motor fibers exhibited clustering along the periphery. Comparison with Existing MethodsPrior exploration of fiber distributions at regenerative interfaces was limited to either quadrant-based density analysis of randomly sampled subregions or qualitative description. This method extends existing sample preparation and microscopy techniques to quantitatively assess immunolabeled fiber distributions within whole nerve cross-sections. ConclusionsThis approach is an effective way to examine the spatial organization of fiber subsets at regenerative electrode interfaces, enabling robust assessment of fiber distributions relative to electrode arrangement.

Performance of combined organic precipitation, electrocoagulation, and electrooxidation in treating anaerobically treated palm oil mill effluents

Palm oil mill effluent (POME), wastewater generated from palm oil production, is known for its extremely high chemical oxygen demand and brownish color. Anaerobic digestion is the primary treatment method for POME in the palm oil industry; however, anaerobically treated POME has high concentrations of residual contaminants and color intensity. This study proposes an approach to treat anaerobically-treated POME in recycled water for industrial applications by integrating preliminary organic precipitation, electrocoagulation, and electrooxidation (EO). The EO process was optimized in terms of the current density, electrolysis time, electrode arrangement, and feed flow rate. At a current density of 60 mA/cm2 and an electrolysis time of 9 min, the EO process with a graphite anode and stainless-steel cathode in the monopolar electrode configuration reduced the phenolic concentration and color in the preliminary-treated POME from 8.95 mg/L and 317.19 ADMI to 0.25 mg/L and 26.10 ADMI, respectively. Additionally, the EO process exhibited a 92.26% efficiency in lowering the ammonium-nitrogen content.

Iron-Catalyzed Laser-Induced Graphitization - Multiscale Analysis of the Structural Evolution and Underlying Mechanism.

The transition to sustainable materials and eco-efficient processes in commercial electronics is a driving force in developing green electronics. Iron-catalyzed laser-induced graphitization (IC-LIG) has been demonstrated as a promising approach for rendering biomaterials electrically conductive. To optimize the IC-LIG process and fully exploit its potential for future green electronics, it is crucial to gain deeper insights into its catalyzation mechanism and structural evolution. However, this is challenging due to the rapid nature of the laser-induced graphitization process. Therefore, multiscale preparation techniques, including ultramicrotomy of the cross-sectional transition zone from precursor to fully graphitized IC-LIG electrode, are employed to virtually freeze the IC-LIG process in time. Complementary characterization is performed to generate a 3D model that integrates nanoscale findings within a mesoscopic framework. This enabled tracing the growth and migration behavior of catalytic iron nanoparticles and their role during the catalytic laser-graphitization process. A three-layered arrangement of the IC-LIG electrode is identified including a highly graphitized top layer with an interplanar spacing of 0.343nm. The middle layer contained γ-iron nanoparticles encapsulated in graphitic shells. A comparison with catalyst-free laser graphitization approaches highlights the unique opportunities that IC-LIG offers and discuss potential applications in energy storage devices, catalysts, sensors, and beyond.

Analysis of medical correlation models using ultrasound tomography and electric impedance tomography

Summary The main goal of the work was to develop a method for the fusion of images from two different measurement techniques. A project has been designed to integrate electrical impedance tomography (EIT) and ultrasonic tomography (UST) data. The next stage was to analyze the correlation between the EIT results and the occurrence of lower urinary tract dysfunctions and establish boundary parameters for visualization and segmentation. Additionally, the relationships between UST data and the dysfunctions were examined, which also required defining parameters for segmentation. The work also involves establishing standards and methods for the arrangement of measurement electrodes, which is crucial for the precision of both techniques. The proposed approach and results constitute an essential step towards implementing more advanced diagnostic tools to improve patient's quality of life by diagnosing lower urinary tract dysfunctions faster and more precisely.

Theory and Experiment of the Limiting Current in Impinging Jet Electrodes

Recently, flow cells with a confined impinging jet type have emerged as a promising hydrodynamic electrochemical setup for non-conventional square model electrodes that cannot be measured in the commonly used rotating disk electrode (RDE) setup1. Due to the complex hydrodynamic flow profiles, these flow cell types usually rely on computational fluid dynamics (CFD) simulations for the description of the local current density profiles and overall current-potential characteristics2. In this work, we present an advanced analytical model of the limiting current in confined impinging jet electrodes and validate the model with experimental data and corresponding CFD simulations.Around 350 parameter sets of the confined impinging jet electrode arrangement were analyzed by varying the inlet diameter (d), distance between inlet-nozzle and electrode (H), electrode radius (RIII), and volume flow rate (V0). Figure 1 shows the proposed analytical solution which separates the electrode into three different diffusion regions: (i) wall-tube region (blue rectangle), (ii) wall-jet region (green rectangle), and finally (iii) radial channel-flow region (orange rectangle). The approach allows predicting the limiting current characteristics for a broad variety of impinging jet electrodes, including the confined impinging jet electrode type. The flow line profiles obtained by CFD simulations are in excellent agreement with the analytically determined regimes with radii RI and RII and flow regime transitions. Very importantly, for the construction of ideal wall-tube electrodes the transition point RI can now be described by our analytical model in high accuracy and requires no more in-depth numerical or experimental studies3. We determined an average relative error over all parameter points compared to the numerical CFD simulations to be 7.8 %. In contrast, the analytical formula for free wall-jets4 to the entire electrode is in the range of 29 %. Furthermore, using a 3D-printed flow cell geometry (H = 0.7 mm; d = 0.5 mm) with the confined impinging jet type, the obtained experimental data confirm the here developed analytical model. The experimental data for different electrode radii (1 mm < R < 3 mm) using the ferrocyanide/ferricyanide redox pair ([Fe(CN)6]4-/[Fe(CN)6]3-) also show good agreement to the analytical model with an average deviation of 6 %.In summary, we have developed an analytical model that allows an accurate prediction of the limiting current for different geometries of the impinging jet electrode. Based on numerical and experimental approaches, our model shows an accuracy of below 10 %, which is very remarkable compared to the current models reported in the literature. The results of this study help to improve the design and construction of electrochemical flow cells based on this electrode type as an alternative to the classic RDE setup.

Efficient Ionovoltaic Energy Harvesting via Water-Induced p-n Junction in Reduced Graphene Oxide.

Water motion-induced energy harvesting has emerged as a prominent means of facilitating renewable electricity from the interaction between nanostructured materials and water over the past decade. Despite the growing interest, comprehension of the intricate solid-liquid interfacial phenomena related to solid state physics remains elusive and serves as a hindrance to enhancing energy harvesting efficiency up to the practical level. Herein, the study introduces the energy harvester by utilizing inversion on the majority charge carrier in graphene materials upon interaction with water molecules. Specifically, various metal electrode configurations are employed on reduced graphene oxide (rGO) to unravel its distinctive charge carriers that experience the inversion in semiconductor type upon water contact, and exploit this characteristic to leverage the efficacy of generated electricity. Through the strategic arrangement of the metal electrodes on rGO membrane, the open-circuit voltage (Voc) and short-circuit current (Isc) have exhibited a remarkable augmentation, reaching 1.05V and 31.6µA, respectively. The demonstration of effectively tailoring carrier dynamics via electrode configuration expands the practicality by achieving high power density and elucidating how the water-induced carrier density modulation occurs in 2D nanomaterials.

Development of a two‐dimensional bipolar electrochemistry technique for high throughput corrosion screening

AbstractBipolar electrochemistry allows testing and analysing the crevice corrosion, pitting corrosion, passivation, general corrosion, and cathodic deposition reactions on one sample after a single experiment. A novel two‐dimensional bipolar electrochemistry setup is designed using two orthogonal feeder electrode arrangements, allowing corrosion screening tests across a far wider potential range with a smooth potential gradient to be assessed. This two‐dimensional bipolar electrochemistry setup was applied here to simultaneously measure for the simultaneous measurement of the nucleation and propagation of pitting and crevice corrosion under a broad range of applied potential on type 420 stainless steel, which has a very short localised corrosion induction time. It reduces the error from corrosion induction to corrosion competition, and all pits and crevice corrosion have no lacy cover. Results show crevice corrosion can gain current density and easier to support its nucleation and propagation at different potential regions more easily than pitting corrosion.

Influence of humidity and air pressure on thrust characteristics of ion wind propulsion systems

Ion wind propulsion systems have potential applications in the field of unmanned aerial vehicle due to their compactness, quiet operation, and simple design. Previous studies have focused on the influences of power source, electrode arrangement, size, and shape on the output thrust characteristics. However, few studies have been performed on the environmental conditions, which can be beneficial for the practical applications of ion wind aircraft in various climatic conditions. In this work, a measurement platform of the output characteristics of ion wind propulsion system under various environmental conditions has been established. The experimental pressure range was 1–0.7 atm, and the relative humidity (RH) range was 30%–92%. The effects of air pressure and humidity, and voltage level on the thrust, thrust-to-power radio (TPR) corona current have been investigated. The results showed that the corona current and thrust of the wire-wing electrode array decreased with RH within the range of 30%– to 80%. Under higher humidity, the corona current and thrust tend to increase at most voltage levels. Moreover, the thrust and current both decreased with reduced pressure when keeping the voltage-to-pressure ratio (U/P) unchanged. It was also found that the thrust was roughly proportional to the square of the pressure. Finally, the possible explanations of the coupled influences on the output characteristics were discussed.

Machine and Deep Learning Trends in EEG-Based Detection and Diagnosis of Alzheimer’s Disease: A Systematic Review

This article presents a systematic review using PRISMA methodology to explore trends in the use of machine and deep learning in diagnosing and detecting Alzheimer’s disease using electroencephalography. This review covers studies published between 2013 and 2023, drawing on three leading academic databases: Scopus, Web of Science, and PubMed. The validity of the databases is evaluated considering essential factors such as the arrangement of EEG electrodes, data acquisition methodologies, and the number of participants. Additionally, the specific properties of the databases used in the research are highlighted, including EEG signal classification, filtering, segmentation approaches, and selected features. Finally, the performance metrics of the classification algorithms are evaluated, especially the accuracy achieved, offering a comprehensive view of the current state and future trends in the use of these technologies for the diagnosis of Alzheimer’s disease.

SURFACE MORPHOLOGY OF SILICON NITRIDE (Si3N4)-TITANIUM NITRIDE (TiN) COMPOSITES USING GRA-RSM STRATEGY ENCOMPASSED WITH EDMed PARAMETERS

This investigation explores the application of electrical discharge machining (EDM) to ceramic composites constructed from Si3N4–TiN (Syalon 501) by testing both square and cylindrical electrodes. Various experimental methods have been employed, including design-of-experiments (DoE), Grey relational analysis (GRA), analysis of variance (ANOVA), confirmation testing, and scanning electron microscopy (SEM), in an effort to optimize machining settings and comprehend their effect on performance. While ANOVA revealed crucial parameter levels influencing overall machining conditions as measured by the grey relational grade (GRG), the sophisticated method of GRA considerably improved the machining characteristics. Significant improvements in the EDM process were shown experimentally, resulting in outstanding results for material removal rate (MRR), surface roughness (SR), and electrode wear rate (EWR). In particular, numerous benefits of the square electrode layout over the more common cylindrical arrangement stood out. All of the aforementioned resulted in an impressively high MRR (measured at 0.0281[Formula: see text]gm/min), a low EWR (at 0.0020[Formula: see text]gm/min), and a significant improvement in SR (at 0.3150[Formula: see text][Formula: see text]m). The GRG value was 0.0163 for the square electrode design, which was excellent, and 0.0025 for the cylindrical electrode, which was significantly better. The optimized parameters were successfully used, especially with the square electrode arrangement, leading to significant improvements in MRR and decreases in EWR. On the other hand, surface quality was negatively affected by larger parameter values, which increased the development of microfractures, particularly when using the square electrode design. In any case, our study provides strong proof that adjusted settings can greatly improve EDM performance, allowing for accurate machining of Si3N4–TiN composites with increased MRR, great surface texture, and reduced electrode wear. In conclusion, our study provides useful information to improve EDM procedures for Si3N4–TiN ceramic composites, as well as practical insights into increasing the efficiency and quality of EDM operations in a variety of industrial sectors.

Structural arrangement, electroconductivical and electrochemical behaviours of solid amino acid-based electrodes

This paper presents the study on the structural dependence of the electroconductivity and electrochemical activity of model amino acids, aspartate and glycine, which are used as solid electrodes in hybrid capacitor systems. It has been established that the presence of carbonyl, aliphatic, and amide functional groups on the surface enhances the electrochemical activity and electrical conductivity. The frequency dependence of conductivity is typical for polymer compounds with a proton conduction mechanism, which is provided by the surface migration of the charge. It was found that deposition on the surface of carbon templates of the amino acids in the formation of biocomposites increases the number of active reaction centers and provides effective electronic charge transport. As a result, it leads to a significant increase in the contribution of pseudocapacitance and capacitance processes. The electrochemical activity was caused by the pseudocapacitive accumulation of charge due to the course of redox reactions with amino acids and capacitive accumulation of charge, which occurs with the participation of amino acids and carbon templates. It has been proven that the porous structure of the carbon nanotubes provides a more dispersed and uniform distribution of amino acids on the surface, which is ensured in the growth of pseudocapacitive charge accumulation.

Enhanced brackish water desalination in capacitive deionization with composite Zn-BTC MOF-incorporated electrodes

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.

Electrocoagulation removal of COD and TDS from real municipal wastewater sourced from the Euphrates River using multipole arrangement

This study investigated the performance of the electrocoagulation (EC) process for removing organic pollutants, as measured by chemical oxygen demand (COD), and reducing total dissolved solids (TDS) from real municipal wastewater sourced from the Euphrates River. A systematic approach was followed, where initial control tests were conducted to identify the optimal electrode configuration, which was a multipole arrangement of aluminum electrodes.The independent operating parameters studied were electrolysis time (10–60 min), applied current (0.2–1.4 A), and mixing speed (50–250 rpm). The response surface methodology (RSM), facilitated by a Box-Behnken design (BBD), was employed to model and optimize the EC process. The developed mathematical models revealed that the COD removal efficiency, final TDS value, and energy consumption were strongly dependent on the coagulation process parameters.The results showed that under the optimized conditions of 60 min of electrolysis time, 1 A of applied current, and 50 rpm mixing speed, a maximum COD removal efficiency of 92.43 % was achieved. At these optimal values, the final TDS concentration was reduced to 1299 ppm. The energy consumption for the batch EC process was also determined, with the lowest value being 5.47 kWh/m3.The findings demonstrate the effectiveness of the electrocoagulation process, particularly when utilizing a multipole electrode arrangement, for the treatment of real municipal wastewater. The developed models and optimization approach can be used to predict the performance and determine the optimal operating conditions for similar wastewater treatment applications. Future research prospects include investigating the removal of other pollutants, integrating the EC process with other treatment technologies, and evaluating the long-term economic feasibility of the system.

A Ground-Based Electrostatically Suspended Accelerometer.

In this study, we have developed an electrostatically suspended accelerometer (ESA) specifically designed for ground use. To ensure sufficient overload capacity and minimize noise resulting from high suspension voltage, we introduced a proof mass design featuring a hollow, thin-walled cylinder with a thin flange fixed at the center, offering the highest surface-area-to-mass ratio compared to various typical proof mass structures. Preload voltage is directly applied to the proof mass via a golden wire, effectively reducing the maximum supply voltage for suspension. The arrangement of suspension electrodes, offering five degrees of freedom and minimizing cross-talk, was designed to prioritize simplicity and maximize the utilization of electrode area for suspension purposes. The displacement detection and electrostatic suspension force were accurately modeled based on the structure. A controller incorporating an inverse winding mechanism was developed and simulated using Simulink. The simulation results unequivocally demonstrate the successful completion of the stable initial levitation process and suspension under ±1g overload.

A Multilayer Doyle-Fuller-Newman Model to Optimise the Rate Performance of Bilayer Cathodes in Li Ion Batteries

Bilayer cathodes comprising two active materials are explored for their ability to improve lithium-ion battery charging performance. Electrodes are manufactured with various arrangements of lithium nickel manganese cobalt oxide Li[Ni0.6Co0.2Mn0.2]O2 (NMC622) and lithium iron phosphate LiFePO4 (LFP) active particles, including in two different discrete sub-layers. We present experimental data on the sensitivity of the electrode C rate performance to the electrode design. To understand the complex bilayer electrode performance, and to identify an optimal design for fast charging, we develop an extension to the Doyle-Fuller-Newman (DFN) model of electrode dynamics that accommodates different active materials in any number of sub-layers, termed the multilayer DFN (M-DFN) model. The M-DFN model is validated against experimental data and then used to explain the performance differences between the electrode arrangements. We show how the different open circuit potential functions of NMC and LFP can be exploited synergistically through electrode design. Manipulating the Li electrolyte concentration increases achievable capacity. Finally the M-DFN model is used to further optimize the best performing bilayer electrode arrangement by adjusting the ratio of the LFP and NMC sub-layer thickness.

Assessment of the Influence of Fabric Structure on Their Electro-Conductive Properties.

Electro-conductive fabrics are key materials for designing and developing wearable smart textiles. The properties of textile materials depend on the production method, the technique which leads to high conductivity, and the structure. The aim of the research work was to determine the factors affecting the electrical conductivity of woven fabrics and elucidate the mechanism of electric current conduction through this complex, aperiodic textile material. The chemical composition of the material surface was identified using scanning electron microscopy energy dispersion X-ray spectroscopy. The van der Pauw method was employed for multidirectional resistance measurements. The coefficient was determined for the assessment of the electrical anisotropy of woven fabrics. X-ray micro-computed tomography was used for 3D woven structure geometry analysis. The anisotropy coefficient enabled the classification of electro-conductive fabrics in terms of isotropic or anisotropic materials. It was found that the increase in weft density results in an increase in sample anisotropy. The rise in thread width can lead to smaller electrical in-plane anisotropy. The threads are unevenly distributed in woven fabric, and their widths are not constant, which is reflected in the anisotropy coefficient values depending on the electrode arrangement. The smaller the fabric area covered by four electrodes, the fewer factors leading to structure aperiodicity.