Effect Of Different Electrode Materials Research Articles

The Voltage-Based Implementation of the Tunneling Mechanism in Aging Models for Lithium-Ion Batteries

Lithium-ion batteries (LIBs) have become one of the most crucial power sources for electronics and electric vehicles due to high energy density, long cycle life, environmental friendliness, etc. Precise explanation and prediction of the aging behavior of LIBs is quickly becoming a hotspot. A solid electrolyte interface (SEI) growth is regarded as the dominant factor of capacity losses in LIBs. However, the previous SEI growth and aging models were based on energy levels. That means the energy barrier related to the Fermi level of SEI and electrode was used as the input parameter. It is not straightforward to implement, especially for industrial applications. Furthermore, the state-of-charge (SoC) and the energy barrier were usually assumed to be constant during (dis)charging, contradicting common sense and affecting the calculations' accuracy.The present work proposes and experimentally validates an advanced voltage-based aging model. The voltage of the anode electrode is adopted as an input parameter in this model. It is easier to introduce dependence of aging on the voltage/SoC of the electrode with this model. It is found that deep delithiation of the anodes and lower SoC of LIBs will mitigate electron tunneling, lower SEI growth, and reduce calendar aging. Commonly used anode materials, such as graphite, Li4Ti5O12, and blended Si/C, are presented as interesting cases to investigate the effects of different electrode materials on the tunneling current profiles during (dis)charging for the first time. The model is instructive and can predict aging in LIBs with various electrode materials. This model and related analyses are beneficial for further optimizing LIB's electronic and electrode properties and as interesting limiting cases for testing battery modeling software.

High-performance flexible piezoelectric sensors based on honeycomb graphene macro-film exploiting auxetic mechanical property

Flexible piezoelectric sensors have received widespread attention in wearable electronics for their ability to convert mechanical energy into electrical energy, while the insufficient output power and complex preparation process have limited their application. In this work, several honeycomb structures based on graphene macro-film (GAMF) were created via laser engraving, which can utilize negative Poisson’s ratio (NPR) properties to improve the output electric performance of flexible piezoelectric sensors. The effect of different electrode materials on the piezoelectric output was investigated in the experiments and compared with the theoretical equations, indicating that the output power of the sensor could be enhanced up to 142 % by improving the materials auxetic mechanical properties. The stability tests have proven that the sensors can operate effectively for a long time under different operating conditions. Moreover, the optimized sensor shows powerful potential for monitoring human movements such as finger tapping, joint bending, and foot stepping. This work opens up a new development path for the preparation of convenient and high-performance wearable electronic devices.

Efficacy and power production performance of constructed wetlands coupled with microbial fuel cells for the advanced treatment of saline tailwater from wastewater treatment plants

In this study, the effects of different electrode materials and salt-tolerant plants on the efficacy and power production performance of constructed wetlands coupled microbial fuel cells (CW-MFCs) were analyzed for the advanced treatment of saline tailwater from wastewater treatment plants (WWTPs). The results showed that when carbon felt was used as the cathode material, the voltage was 165.45 ± 14.90 mV after system stabilization, the maximum power density was 3.20 mW/m2 when the current density was 25.58 mA/m2, and the power production performance of carbon felt was better than that of common titanium mesh and granular activated carbon-stainless steel mesh cathode materials (p < 0.05). When the two groups of systems were operated and stabilized, the average removal rates of TN, TP, NH4+-N and COD in RS-CW-MFC were 86.48 %, 88.1 %, 82.67 % and 88.96 %, respectively, and those of TN, TP, NH4+-N and COD in RN-CW-MFC were 84.33 %, 87.34 %, 81.63 % and 87.64 %, respectively. Salinity enhanced the power production efficiency by increasing ionic strength and decreasing the internal resistance of the system. The microbial community in the saline tailwater systems gradually evolved toward salt-tolerant species, which enhanced the power production efficiency of the system without affecting the treatment of traditional pollutants in the CW-MFC systems.

The effects of different electrode materials on the electric field-assisted co-composting system for the soil remediation of heavy metal pollution

The electric field-assisted composting system (EACS) is an emerging technology that can enhance composting efficiency, but little attention has been given to electrode materials. Herein, an EACS was established to investigate the effects of electrode materials on humic substance formation and heavy metal speciation. Excitation-emission matrix analysis showed that carbon-felt and stainless-steel electrodes increased humic acid (HA) by 48.57 % and 47.53 %, respectively. In the EACS with the carbon-felt electrode, the bioavailability factors (BF) of Cu and Cr decreased by 18.00 % and 7.61 %, respectively. Despite that the stainless-steel electrodes decreased the BF of As by 11.26 %, the leaching of Cr, Ni, Cu, and Fe from the electrode itself is an inevitable concern. Microbial community analyses indicated that the electric field increased the abundance of Actinobacteria and stimulated the multiplication of heavy metal-tolerant bacteria. Redundancy analysis indicates that OM, pH, and current significantly affect the evolution of heavy metal speciation in the EACS. This study first evaluated the metal leaching risk of stainless-steel electrode, and confirmed that carbon-felt electrode is environment-friendly material with high performance and low risk in future research with EACS.

Computational Modeling of Catheter-based Radiofrequency Renal Denervation with Patient-specific Model.

Renal sympathetic denervation (RDN) is an effective approach for uncontrolled hypertension. Although several studies have compared the ablation characteristics at various locations, there is no direct comparative study on the effect of ablation in main and branch renal artery (RAs) and different electrode materials. The study aims to investigate the effect of different electrode materials (copper, gold, and platinum) and positions (proximal, middle, or distal site) on ablation. A 3D patient-specific renal artery model and a unipolar model (470 kHz) were constructed to mimic RDN. Two therapeutic strategies, including main (site 1 and 2) and branch (site 3) ablations were simulated with three electrode materials. The finite element method was used to calculate the coupled electric-thermal-flow field. Maximum lesion depth, width, area, and lesion angle were analyzed. The results showed that the difference in lesion width and depth was no mere than 0.5 mm, and the maximum difference value in lesion area is 0.683 mm2 among three electrode materials. The lesion angle of proximal site 1 versus middle site 2 was 58.39 ° and 52.23 °, but the difference between distal site 3 and site 1, or site 2 was 29.19 ° and 35.35 ° respectively. There is no significant difference in the use of the three electrode materials, and ablation at the distal site of the artery is more effective.Clinical Relevance-This provides a reference for the selection of RF electrode materials and ablation locations.

An Innovative Smart Concrete Anchorage with Self-Stress Sensing Capacity of Prestressing Stress of PS Tendon.

An innovative smart concrete anchorage (SCA) has been developed for monitoring the stress of prestressing (PS) tendons by utilizing smart ultra-high-performance concrete (UHPC). The smart UHPC contained 2 vol% steel fibers and fine steel slag aggregates instead of silica sands. The effects of different electrode materials, arrangements, and connectors on the self-stress sensing capacity of the SCA are discussed. A prototype SCA demonstrated its feasibility and sufficient self-stress sensing capacity to be used in monitoring the prestressing loss of the PS tendon. As the tensile stress of the PS tendon increased from 0 to 1488 MPa, the fractional change in resistivity (FCR) of the prototype SCA, with horizontally paired copper wire electrodes and a plug-in type connector, decreased linearly from 0% to −1.53%, whereas the FCR increased linearly from −1.53% to −0.04% as the tensile stress of the PS tendon decreased from 1488 to 331 MPa.

The effects of different electrode materials on seed germination of Solanum nigrum L. and its Cd accumulation in soil

The effects of different electrode on Solanum nigrum L. seed germination were determined. The result showed that germination percentage (GP) of seeds in treatment T2 (titanium electrode) was 26.6% higher than in control (CK, without electric field). High potassium and calcium concentrations were beneficial for seed enzymatic activity in treatment T2, which could partly explain the increase in GP. Cd accumulation (μg/pot) in S. nigrum treated with any electric field was significantly higher (p<0.05) than in CK without electric field. Specifically, Cd accumulation under the treatment T3 (stainless steel electrode) was the highest both in roots and shoots; this accumulation in shoots and roots were 74.7 % and 67.4 % higher for stainless steel than in CK. This increase must have been associated with a higher Cd concentration in plants and did not exert a significant effect on the biomass. In particular, Cd concentrations in roots and shoots under stainless steel treatment were both significantly higher than in CK (p<0.05), which had to be related to the higher available Cd concentration in the soil in the middle region. Furthermore, it could be attributed to altered soil pH and other soil properties. Moreover, none of the biomasses were significantly affected (p<0.05) by different electrode materials compared to CK.

Dewaterability enhancement and sulfide mitigation of CEPT sludge by electrochemical pretreatment

Dewatering and sulfide control are the key challenges in treating chemically enhanced primary treatment (CEPT) sludge. In this study, an electrochemical pretreatment (EPT) approach with the input of 10 V/800 mA was explored for simultaneously improving the dewaterability of CEPT sludge and eliminating its sulfide production. The effects of different electrode materials (carbon and titanium) and EPT durations (from 5 to 15 min) were documented to reveal the underlying EPT mechanism. EPT with titanium electrodes (titanium-EPT) led to limited improvement in dewaterability and sulfide control. EPT with carbon electrodes (carbon-EPT) for 15 min, however, led to decreases in capillary suction time and specific resistance in filtration of over 80% and the suppression of about 99% of hydrogen sulfide (H2S(g)) production over 5 days of anaerobic storage. Analysis of the characteristics of treated CEPT sludge revealed that carbon-EPT disintegrated sludge flocs with ∼70% reduction in sludge particle sizes and release of aromatic and tyrosine protein-like substances, thus enhancing sludge dewaterability. The sulfur balance in the liquid and gaseous phases showed that most of the sulfur-containing compounds remained in the solid phase as aliphatic sulfur and sulfonic acid after carbon-EPT, thereby mitigating sulfide emission. While the pattern of sulfur distribution in sludge with titanium-EPT was dominated by sulfide, it was similar to the control sample. Reduction in bacteria associated with sulfide production (i.e., Lachnospiraceae) in CEPT sludge after carbon-EPT also contributed to sulfide elimination. This study demonstrates that EPT can be a superior option for simultaneously enhancing the dewaterability of CEPT sludge and mitigating its sulfide production.

Processing of printed piezoelectric microdisks: effect of PZT particle sizes and electrodes on electromechanical properties

Nowadays, micro-scale piezoelectric devices with high sensitivity are much in demand for transducer technologies. This work suggests a low cost technology consisting of a screen-printing process associated with a sacrificial layer for preparation of microceramic-disks. These printed microdisks are based on a PZT layer sandwiched between two printed electrodes. The printed microdisks can be released from substrates by co-firing, leading to a complete decomposition of the sacrificial layer. The effect of different electrode materials (Au and Ag/Pd) on the releasing behavior is described. Uniform releasing is obtained by Ag/Pd electrodes whereas Au electrodes perform partial sticking on the substrates. Furthermore, the printed microdisks made of different PZT particle sizes are compared in terms of microstructure, electromechanical, and dielectric properties. The dense microdisks obtained from nanometric PZT particles and Ag/Pd electrodes generate high values of effective electromechanical coupling coefficient (45%) and relative permittivity (1200). Therefore, these printed microdisks are considered to be potential candidates for different sensing and actuating applications.

Effects of electrode parameters on sewage disinfection by underwater pulsed arc discharge

Underwater pulsed arc discharge is a potential method applying on sewage disinfection. The disinfection effect may be influenced by electrode parameters. In this paper, effects of different electrode materials, gap distances and electrode shapes were studied with underwater pulsed arc discharge. The following results were obtained through experiments. Reactive species production of different materials are arranged from largest to smallest is W, Titanium alloy and Ti. However, the difference of pressure amplitude among three materials is less than 0.88%. Under the influence of these physical and chemical effects, with 800 s’ treatment, the residual Escherichia coli content of W, Titanium alloy, and Ti is 103.77 CFU/L, 104.29 CFU/L, and 104.87 CFU/L. W shows the best disinfection effect, which generated 2.2 orders reduction with an energy density of 0.6 J/mL. It can be found that the disinfection effect has a positive correlation with the electron work function of material. When the voltage is constant, the discharge dispersion increases as the gap distance increases. At a discharge voltage of 4.5 kV, with the gap distance changing from 0.25 to 1.50 mm, the total spectral intensity decreases, and the pressure amplitude increases first and then decreases. The study shows disinfection efficiency keeps the same trend with the change of pressure wave. And there is an optimal distance in sewage disinfection. Under the experimental conditions in this manuscript, the optimal distance is 1 mm. For the three electrode shapes, the pressure amplitude and total spectral intensity of rod shape are higher than hemisphere and cone shape. As a result, the rod electrode presented the highest disinfection effect, which residual Escherichia coli content is 103.63 CFU/L after 800 s’ treatment.

Effects of Different Electrode Materials on High-speed Electrical Discharge Machining of W9Mo3Cr4V

In order to break through the limit in material removal rate (MRR) of electrical discharge machining (EDM), electric arc machining (EAM), as a new and high-speed processing method, is used to machine difficult-to-machine materials. This method has an exciting high MRR with tens times increase in EDM and a low relative electrode wear ratio (REWR) when machining W9Mo3Cr4V. The electrode material is an important factor that affects the processing cost and quality of EAM. In this paper, traditionally conductive metal materials were used as electrode materials to process W9Mo3Cr4V in EAM, including brass (H62), copper (T2), stainless steel 304, aluminum alloy 6061 and graphite (C). Experimental results show that tubular graphite (C) is the best electrode material for EAM. Additionally, when tubular graphite with 16mm external diameter and 12mm internal diameter is used as tool electrode, the effects of processing parameters (peak current, electrode polarity, electrode speed and flushing pressure) are also investigated in present study. MRR, REWR, white layer thickness (WLT) and surface roughness (Rz) are selected as output responses.

Study on Breakdown Probability of Multimaterial Electrodes in EDM

With the development of EDM technology, some multimaterial electrodes which have some special functions are regularly taking the place of traditional single material electrodes on some machining occasions and becoming widely used. In this paper, the influence of material on discharge breakdown in EDM with multimaterial electrodes is studied. A comparison model about material influence on discharge breakdown under both single discharge condition and continuous discharge condition is established, and the material property factors affecting the probability of discharge breakdown are also analyzed. Finally, a series of experiments are carried out to study the effects of different electrode materials on the discharge breakdown of EDM, a fitting formula of breakdown probability is presented, and the effectiveness of the comparison model is also verified by comparing with experimental results.

Manipulating Ferroelectrics through Changes in Surface and Interface Properties.

Ferroelectric materials are used in many applications of modern technologies including information storage, transducers, sensors, tunable capacitors, and other novel device concepts. In many of these applications, the ferroelectric properties, such as switching voltages, piezoelectric constants, or stability of nanodomains, are crucial. For any application, even for material characterization, the material itself needs to be interfaced with electrodes. On the basis of the structural, chemical, and electronic properties of the interfaces, the measured material properties can be determined by the interface. This is also true for surfaces. However, the importance of interfaces and surfaces and their effect on experiments are often neglected, which results in many dramatically different experimental results for nominally identical samples. Therefore, it is crucial to understand the role of the interface and surface properties on internal bias fields and the domain switching process. Here, the nanoscale ferroelectric switching process and the stability of nanodomains for Pb(Zr,Ti)O3 thin films are investigated by using scanning probe microscopy. Interface and surface properties are modulated through the selection/redesign of electrode materials as well as tuning the surface-near oxygen vacancies, which both can result in changes of the electric fields acting across the sample, and consequently this controls the measured ferroelectric and domain retention properties. By understanding the role of surfaces and interfaces, ferroelectric properties can be tuned to eliminate the problem of asymmetric domain stability by combining the effects of different electrode materials. This study forms an important step toward integrating ferroelectric materials in electronic devices.

Kilohertz Electrical Stimulation Nerve Conduction Block: Effects of Electrode Material.

Kilohertz electrical stimulation (KES) has enabled a novel new paradigm for spinal cord and peripheral nerve stimulation to treat a variety of neurological diseases. KES can excite or inhibit nerve activity and is used in many clinical devices today. However, the impact of different electrode materials on the efficacy of KES is unknown. We investigated the effect of different electrode materials and their respective charge injection mechanisms on KES nerve block thresholds using 20- and 40-kHz current-controlled sinusoidal KES waveforms. We evaluated the nerve block threshold and the power requirements for achieving an effective KES nerve block. In addition, we evaluated potential effects on the onset duration and recovery of normal conduction after delivery of KES. We found that thresholds and the onset and recovery of KES nerve block are not a function of the electrode material. In contrast, the power dissipation varies among electrode materials and is a function of the materials' properties at high frequencies. We conclude that materials with a proven track record of chronic stability, both for the tissue and electrode, are suitable for developing KES nerve block therapies.

Effect of Different Electrode Materials on the Electropolymerization Process of Aniline in Nitric Acid Media

The electropolymerization process of aniline on different electrode surfaces such as Pt, Au, RuTi and polyaniline film in nitric acid solution containing 1 M aniline was investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Proposed electrical equivalent circuits were used to give a further analysis. Results show that the electrode materials accelerate the aniline electropolymerization remarkably as a catalyst, especially the electrochemical oxidation process of monomer aniline to its cation radical, which is the key step to incur the electropolymerization reaction of aniline on the electrode surface. The polymerization of aniline on RuTi electrode has the lowest reaction resistance for its adsorption sites, and the catalytic effects of these different electrodes decrease in the order: RuTi > polyaniline film > Pt > Au. The results also show that several states of polyaniline films are formed during the potential linear scan process in nitric acid solution and the corresponding oxidation and reduction reaction are reversible.

Simulations and design of microfabricated interdigitated electrodes for use in a gold nanoparticle enhanced biosensor.

Microfabricated interdigitated electrode chips have been designed for use in a unique gold-nanoparticle based biosensor system. The use of these electrodes will allow for simple, accurate, inexpensive, and portable biosensing, with potential applications in diagnostics, medical research, and environmental testing. To determine the optimal design for these electrodes, finite element analysis simulations were carried out using COMSOL Multiphysics software. The results of these simulations determined some of the optimal design parameters for microfabricating interdigitated electrodes as well as predicting the effects of different electrode materials. Finally, based on the results of these simulations two different kinds of interdigitated electrode chips were made using photolithography.

电极材料对IGZO薄膜晶体管性能的影响

Indium gallium zinc oxide thin film transistors(IGZO-TFTs) with bottom-gate top structure were fabricated on n-type silicon substrates using radio frequency(RF) magnetron sputtering method.Three kinds of metal material such as Au,Cu,and Al were used to fabricate electrode,respectively,and the effects of different electrode materials on IGZO TFT performance were investigated. The output characteristic and transfer characteristic of the TFT devices were tested. The best performance was obtained when Au was used to fabricate electrode,its saturation output current was 17. 9 μA,and on-off current ratio was up to 1. 4 ×106. In addition,the contact characteristics between three kinds of electrodes and IGZO thin film were analyzed based on their work function. Au electrode had the smallest contact resistance of these three metal according to the TLM(transmission line model) theory.

Effects of different electrode materials on the performance of lithium tetrafluorooxalatophosphate (LiFOP) electrolyte

The cycling performance of LiPF4(C2O4) electrolyte is compared with LiPF6 electrolyte in the presence of several different electrode materials. The cycling of MCMB/LiNi1/3Co1/3Mn1/3O2 and natural graphite/LiFePO4 cells provides very similar performance for both electrolytes. However, MCMB/LiMn2O4 cells have a lower initial reversible capacity with LiPF4(C2O4) electrolytes. A detailed analysis of the surface films on both the cathode and the anode via X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) was conducted. The performance differences are attributed to the anode as opposed to the cathode.

Characteristic Analysis of AC Plasma Arc in Water

An experimental system of AC arc discharge in water was designed with pole-pole electrodes and a peak voltage of 1500 V and a test circuit was set up using virtual instrument technology. The mechanism of an AC plasma arc generated in water was analyzed. The voltage-current characteristic of the AC plasma arc was obtained from the waveform. The temperature characteristic was tested with a spectrum diagnosis system, and the effect of different electrode materials on the striking voltage and peak current was analyzed. The results show that when a power supply of 6 kW is applied on electrodes with a gap of 2 mm in water, the striking voltage is from 900 V to 1300 V, the arc voltage is from 40 V to 100 V, the arc current is from 2 A to 7 A, and the zero rest period is from 1 ms to 2 ms. In addition, the arc voltage and current are different for electrodes in aluminum, copper and stainless steel. The arc voltage is lower and the current is higher for an aluminum electrode than those for copper and stainless steel ones. The highest temperature of the arc is 7643 K.

Evaluation of the electrical and physical properties of thin calcium titanate high-k insulators for capacitor applications

Thin calcium titanate (CaTiO3) films are investigated as promising insulator materials with very high-k values for future microelectronic devices such as metal-insulator-metal (MIM) capacitors and field-effect transistor gate stacks. MIM stacks were deposited by sputtering under UHV conditions without breaking vacuum. A capacitance equivalent thickness of 1.3 nm with a leakage current density of 1×10−7 A/cm2 at 1 V was achieved with deposition temperatures of 550 °C on Pt as bottom electrode. The effect of different electrode materials was studied, resulting in leakage densities correlating directly to the different work function values. grazing incidence x-ray diffraction and high-resolution transmission electron microscopy images are analyzed to study the crystallization behavior. As grown CaTiO3 at 550 °C exhibits crystallites in an amorphous matrix. A dielectric constant of k≈93 was obtained for crystallized films.