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To realize the on-line detection of pH value of heterogeneous systems and provide stable reference potential, the polydopamine modified Ag/AgCl solid film reference electrode was developed by magnetron sputtering deposition of silver film and chlorination of NaClO solution to obtain AgCl layer and dopamine deposition modification film. The stability, reversibility and cyclic voltammetry characteristics of polydopamine modified electrodes with deposition times of 4, 8, 12 and 16 h were compared in phosphate buffered saline (PBS) solution. The results show that the standard deviation of response potential of reference electrode in PBS solution is about 1.00 mV. It can recover to relatively stable potential in different pH buffer solutions, and the deviation of the reference electrode is less than 5.00 mV with good reversibility. The response potential drift is small in 50 cyclic voltammetry tests. According to the sensitivity of the reference electrode ranging from 2.00 to 2.50 mV/pCl, the polydopamine modified electrode is not sensitive to chloride ion concentration, which confirms that the polydopamine modified reference electrode is feasible. The reference electrode with deposition time of 12 h has the best comprehensive performance in various tests. The application tests illuminate that the reference electrode is more suitable for the detection of pH of cultivation substrate. [ABSTRACT FROM AUTHOR]

The battery system is the critical component to supporting the next generation of advanced power grids. However, parasitic lithium plating reactions can be triggered by improper charging and discharging strategies, leading to a significant compromise of the charge-discharge performance of batteries. Centered on ternary lithium-ion batteries, the degradation of charge performance due to lithium plating is elucidated through the utilization of a reference electrode-based approach in this study, followed by the implementation of measures to regulate safe charging currents. Diverse temperature-dependent charge-discharge cycling experiments are initially designed to evaluate batteries under both low-temperature and high-temperature cycling. Subsequently, the calibration of safe charging curves is conducted using a reference electrode, and the negative electrode potential of batteries undergoing high-temperature cycling is analyzed. The occurrence of lithium plating in batteries subjected to high-temperature cycling is identified, resulting in an average charging current reduction of 61.7% compared to pristine cells. Furthermore, a comprehensive charge state-temperature-current contour map is established for batteries with lithium plating. A reduction of 69.84% in the charging current region above 200 A is demonstrated through comparative analysis with the contour map of pristine batteries. A quantitative metric for assessing the degradation of charge performance in batteries with lithium plating is provided by this study, underscoring the necessity of considering these factors in the comprehensive lifecycle management of lithium-ion batteries.

As an effective decoupling and quantification tool, reference electrodes (REs) are increasingly utilized in the development of high‐performance and high‐safety lithium (Li) batteries. However, it is still challenging to construct durable REs in practical battery systems given the sophistication of multi‐field interactions. In this contribution, the two‐stage failure mechanism of Li metal REs set inside working batteries is determined, including the active material loss period due to spatial redistribution behavior and then accelerated failure period based on mixed potential theory, which greatly threatens the dynamic service lifespan of REs. Furthermore, the targeted encapsulation strategy is proposed to control the structural vulnerability issue of Li metal REs. Compared to the unmodified RE, the encapsulated RE is validated feasible to kinetically mitigate the redistribution current through it via designed model experiments. Benefited from the improved structural stability, the encapsulated RE achieved twofold lifetime prolongation in 1 Ah pouch full cells during cycling. This work reveals the neglected structural failure mechanism of Li metal REs in operation and provides fresh design implications toward more durable REs in working batteries, with which deeper insights into battery landscape will be acquired. [ABSTRACT FROM AUTHOR]

Lithium plating can cause capacity fade and thermal runaway safety issues in lithium-ion batteries. Therefore, accurately detecting the amount of lithium plating on the surface of the battery's negative electrode is crucial for battery safety. This is especially crucial in high-energy-density applications such as battery energy storage systems or in electric vehicles (EVs). Early detection of lithium plating is crucial for evaluation of reliability and longevity. It also serves as a method for early diagnostics in practical industrial applications or infrastructure, such as EV transportation. This can enhance its impact on customers. This study validates the effectiveness of titration gas chromatography (TGC) technology in quantitatively detecting lithium plating on graphite negative electrodes in lithium-ion batteries. The results show that it can detect a minimum of 2.4 μmol of metallic lithium. Compared with the heating direct current resistance and reference electrode methods, which can be used to perform only qualitative dendrite detection, TGC has a wider range of detection. Compared with the nuclear magnetic resonance (NMR) method with higher quantitative detection accuracy, the maximum difference between the detection results of the two methods was only 7.2%, but the TGC method had lower cost and higher implementation convenience. In summary, among various dendrite detection methods, the TGC method can not only realize the effective quantitative detection of lithium plating, but also comprehensively consider its detection range, implementation convenience, cost, and detection accuracy, indicating that it is suitable for engineering applications and has the prospect of realizing large-scale quantitative detection of lithium plating in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Copyright of Electric Power Engineering Technology is the property of Editorial Department of Electric Power Engineering Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article it is proved that carbon pastes with ionic liquids (ILs) are a promising material for transducers of reference electrodes, which favors their miniaturization. Two ILs were used: 1‐(2‐hydroxyethyl)‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (IL1) and 1‐(2‐methoxyethyl)‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (IL2). They acted both as a binder of carbon paste and potential‐determining component. ILs were also used in polymeric membrane of reference electrodes what ensured continuity of IL phase between carbon paste and the polymeric membrane and resulted in enhancement of electrode potential stability. It was shown that application of IL as a carbon paste binder is superior to conventional plasticizer and allows for significant increase of reference electrode potential stability. Different types of carbon materials were also tested during research: commercialy available graphite powder and graphene oxide obtained from waste biomass – palm kernel shells. It was observed that both the type of carbon paste material and IL influences reference electrode work parameters. Utilization of IL with less lipophilic cation resulted in higher potential stability of the reference electrodes. Application of graphite paste‐based transducers resulted in higher potential stability of reference electrodes in sodium perchlorate and TMA chloride solutions while using palm kernel shell graphene oxide paste – based transducers caused enhancement of reference electrode long‐term potential stability. The results indicate biomass‐derived graphene oxide can be successfully applied as a construction material of reference electrode. [ABSTRACT FROM AUTHOR]

Molten salts such as 2LiF-BeF2 (FLiBe) have been proposed as coolants for advanced nuclear fission and fusion reactors. Critical to the design, licensing and operation of these reactors is characterization and understanding of the chemical behavior and mass transport of activation and fission products, corrosion products, and other solutes in the coolant. Electrochemical techniques are a powerful suite of tools for probing these phenomena. The design of an experimental cell for molten salt electrochemistry is described herein. As a demonstration of this design, details of the experimental methods used to conduct electrochemical experiments with molten FLiBe with addition of LiH are provided. Decommissioning of the cell is considered from the point of view of decontamination and waste generated. Main features of the cell include:•Suitable for operation up to 800 °C; suitable for operation inside and outside of a glovebox.•Enables sweep gas, gas sampling and analysis; enables addition of solid and liquid materials during operation.•Supports a variety of electrode materials and arrangements.

Abstract In some compound muscle action potentials (M waves) recorded using the belly–tendon configuration, the tendon electrode makes a noticeable contribution to the M wave. However, this finding has only been demonstrated in some hand and foot muscles. Here, we assessed the contribution of the tendon potential to the amplitude of the vastus lateralis, biceps brachii and tibialis anterior M waves, and we also examined the role of this tendon potential in the shoulder‐like feature appearing in most M waves. M waves were recorded separately at the belly and tendon locations of the vastus lateralis, biceps brachii and tibialis anterior from 38 participants by placing the reference electrode at a distant (contralateral) site. The amplitude of the M waves and the latency of their peaks and shoulders were measured. In the vastus lateralis, the tendon potential was markedly smaller in amplitude (∼75%) compared to the belly M wave (P = 0.001), whereas for the biceps brachii and tibialis anterior, the tendon and belly potentials had comparable amplitudes. In the vastus lateralis, the tendon potential showed a small positive peak coinciding in latency with the shoulder of the belly–tendon M wave, whilst in the biceps brachii and tibialis anterior, the tendon potential showed a clear negative peak which coincided in latency with the shoulder. The tendon potential makes a significant contribution to the belly–tendon M waves of the biceps brachii and tibialis anterior muscles, but little contribution to the vastus lateralis M waves. The shoulder observed in the belly–tendon M wave of the vastus lateralis is caused by the belly potential, the shoulder in the biceps brachii M wave is generated by the tendon potential, whereas the shoulder in the tibialis anterior M wave is caused by both the tendon and belly potentials.

Glass pH sensors are unsuitable for in vivo biomedical, clinical, or food applications because of the brittleness of glass, the difficulty in measuring small volumes and complicated matrix, and the necessity of calibration. Enamel structures such as glass/stainless steel (SUS) may substitute glass-based pH electrodes. This study developed new reference electrodes for pH sensors using ternary Ag2O–TeO2-MaOb (M = B, Ge, and P) glass and glass/SUS. The effect of the partial replacement of TeO2 in Ag2O–TeO2 glasses with B2O3, GeO2, and P2O5 on the pH sensitivity was investigated. (1) The effect of the partial replacement on the pH 4–9 sensitivity, which is defined as 100% for the ideal working electrode and 0% for the ideal reference electrode estimated from pH potential, became prominent in the order of GeO2, B2O3, and P2O5 in glass electrodes. Ag2O–TeO2–B2O3 glasses showed the lowest pH 7–9 sensitivity of 1% among the present electrodes. Ag2O–TeO2–P2O5 glasses showed the lowest pH 4–9 sensitivities of 24–33% among the present electrodes. (2) 25Ag2O･55TeO2･20P2O5/SUS showed a very low pH 4–9 sensitivity of 5% in glass/SUS electrodes. In this case, AgP2 may be responsible for the low pH 4–9 sensitivity because only AgP2 was detected from XRD measurements, and a small particle on the surface was observed in AFM observations. On the other hand, the crystallization of the glass matrix of 25Ag2O･55TeO2･20P2O5/SUS was suppressed by adding P2O5. Thus, 25Ag2O･55TeO2･20P2O5/SUS is a candidate for a robust KCl-leakless reference electrode for pH sensors.

Fluoroethylene carbonate (FEC) and vinylene carbonate (VC) are considered the most effective electrolyte additives for improving the solid electrolyte interphase (SEI) of Si‐containing anodes while lithium difluorophosphate (LiDFP) is known to improve the interphases of cathode materials and graphite. Here, we combine VC, FEC, and different amounts of LiDFP in a highly‐concentrated electrolyte to investigate the effect on Si‐dominant anodes in detail. Cycle life tests, electrochemical impedance spectroscopy and rate tests with anode potential monitoring were conducted in Si/NCM pouch cells. The results reveal that adding LiDFP to the electrolyte improves all performance criteria of the full cells, with a concentration of 1 wt% being the optimal value for most cases. Post‐mortem analyses using scanning electron microscopy and x‐ray photoelectron spectroscopy showed that a more beneficial SEI film was formed for higher LiDFP concentrations, which led to less decomposition of electrolyte components and a better‐maintained anode microstructure. [ABSTRACT FROM AUTHOR]

Investigating Na‐ion battery (SIB) materials is complicated by the absence of a well‐performing (reference) electrode material since sodium metal cannot be considered as a quasi‐reference electrode. Taking advantage of the activity of both Ni and Mn, herein, the P2‐type and Mn‐rich Na0.6Ni0.22Al0.11Mn0.66O2 (NAM) material, known to be an excellent positive electrode, is investigated as a negative electrode. To prove NAM stability as both positive and negative electrode, symmetric cells have been assembled without pre‐sodiation, which showed a reversible capacity of 73 mA h g−1 and a remarkable capacity retention of 82.6 % after 500 cycles. The outstanding cycling performance is ascribed to the high stability of the active material at both the highest and lowest Na‐ion storage plateaus and the rather limited electrolyte decomposition and solid‐electrolyte‐interphase (SEI) formation occurring. The long‐term stability of NAM at both electrodes enables its use as a "reference" electrode for the investigation of other positive and negative electrode materials for SIBs, resembling the role played by lithium titanate (LTO) and lithium iron phosphate (LFP) in LIBs. [ABSTRACT FROM AUTHOR]

Abstract Investigating Na‐ion battery (SIB) materials is complicated by the absence of a well‐performing (reference) electrode material since sodium metal cannot be considered as a quasi‐reference electrode. Taking advantage of the activity of both Ni and Mn, herein, the P2‐type and Mn‐rich Na0.6Ni0.22Al0.11Mn0.66O2 (NAM) material, known to be an excellent positive electrode, is investigated as a negative electrode. To prove NAM stability as both positive and negative electrode, symmetric cells have been assembled without pre‐sodiation, which showed a reversible capacity of 73 mA h g−1 and a remarkable capacity retention of 82.6 % after 500 cycles. The outstanding cycling performance is ascribed to the high stability of the active material at both the highest and lowest Na‐ion storage plateaus and the rather limited electrolyte decomposition and solid‐electrolyte‐interphase (SEI) formation occurring. The long‐term stability of NAM at both electrodes enables its use as a “reference” electrode for the investigation of other positive and negative electrode materials for SIBs, resembling the role played by lithium titanate (LTO) and lithium iron phosphate (LFP) in LIBs.

In some compound muscle action potentials (M waves) recorded using the belly–tendon configuration, the tendon electrode makes a noticeable contribution to the M wave. However, this finding has only been demonstrated in some hand and foot muscles. Here, we assessed the contribution of the tendon potential to the amplitude of the vastus lateralis, biceps brachii and tibialis anterior M waves, and we also examined the role of this tendon potential in the shoulder‐like feature appearing in most M waves. M waves were recorded separately at the belly and tendon locations of the vastus lateralis, biceps brachii and tibialis anterior from 38 participants by placing the reference electrode at a distant (contralateral) site. The amplitude of the M waves and the latency of their peaks and shoulders were measured. In the vastus lateralis, the tendon potential was markedly smaller in amplitude (∼75%) compared to the belly M wave (P = 0.001), whereas for the biceps brachii and tibialis anterior, the tendon and belly potentials had comparable amplitudes. In the vastus lateralis, the tendon potential showed a small positive peak coinciding in latency with the shoulder of the belly–tendon M wave, whilst in the biceps brachii and tibialis anterior, the tendon potential showed a clear negative peak which coincided in latency with the shoulder. The tendon potential makes a significant contribution to the belly–tendon M waves of the biceps brachii and tibialis anterior muscles, but little contribution to the vastus lateralis M waves. The shoulder observed in the belly–tendon M wave of the vastus lateralis is caused by the belly potential, the shoulder in the biceps brachii M wave is generated by the tendon potential, whereas the shoulder in the tibialis anterior M wave is caused by both the tendon and belly potentials. New Findings: What is the central question of this study?Does a tendon electrode make a noticeable contribution to the belly–tendon M wave in the vastus lateralis, biceps brachii and tibialis anterior muscles?What is the main finding and its importance?Because the patellar tendon potential is small in amplitude, it hardly influences the amplitude and shape of the belly–tendon M wave of the vastus lateralis. However, for the biceps brachii and tibialis anterior muscles, the potentials at the tendon sites show a large amplitude, and thus have a great impact on the corresponding belly–tendon M waves. [ABSTRACT FROM AUTHOR]

A reference electrode is a half-cell (an electrode) with a stable, well-defined and highly reproducible electrode potential. A vast number of electrodes have been developed for different applications. They are briefly presented. For the common types, the advantages and drawbacks are discussed. Practical hints for daily use are provided.

Reference electrodes (REs) play a crucial role in the accurate assessment and control of battery potentials, but their confidence is overestimated. Researchers have tracked the source of the error to the RE design that blocks the lithium‐ion path between anode and cathode. These errors or potential deviations are mostly modeled or less‐frequently estimated after observing Li plating post‐mortem. This is the first study to showcase an experimental method that allows a more precise error quantification in‐operando of a RE. The key idea is to relate the error‐affected reference potential to an unaffected quantity, such as the cell dilatation. Although our experimental setups are special, this approach can also be applied to different setups and REs. Using the presented method, we provoked Li plating in NMC811/graphite pouch cells and determined the potential deviation of our perforated RE to be 12 mV under fast charging conditions. In contrast to previous studies, we found the error to be positive, offering a new explanation of the error mechanism of REs. [ABSTRACT FROM AUTHOR]

In electrochemical CO2 reduction reactors, polymer electrolyte membrane (PEM) reactors, also known as zero-gap cells, have great potential for achieving significant CO2 reduction. Because these cells have a thin reactor core with a thickness of several hundred micrometers, it is difficult to determine their internal voltage distribution. To determine the anode voltage, ohmic loss in the membrane, and cathode voltage in the PEM reactors, we set three reference electrodes in the reactor and investigated the voltage values obtained from each reference electrode. We demonstrated that the reference electrode in contact with the anion exchange membrane extending to the outside of the cell provides the most reliable voltage. The voltage measured by this reference, combined with the resistance of the exchange membrane obtained through electrochemical impedance spectroscopy, provides a breakdown of the voltage inside the cell. [ABSTRACT FROM AUTHOR]

Purpose Perineal electromyography (EMG) is a crucial part of urodynamic studies. Many researchers focused on the standardization of techniques in urodynamics, but no study has yet evaluated the differences with various reference electrode placements. The aim of this study was to determine the optimal placement of the reference electrode for recording pelvic floor activity in urodynamic studies. Methods Children over 6 years of age without anatomic or neurological abnormalities were invited to participate in the study. Four reference electrodes were placed on the right kneecap, the inner surface of the right inner thigh, the right anterior iliac spine (AIS), and the skin over the left gluteal muscles for simultaneous recording. The EMG signal formed by pelvic contraction during forceful straining was recorded both in the supine and sitting positions. The root mean square (RMS) value of each muscle contraction signal was calculated. Results Twenty-one participants (10 boys and 11 girls) were included. The mean age was 10.19±3.20 years. The highest RMS values were obtained with the reference electrode on the thigh in the supine position and the AIS in the sitting position. Significant differences were found between the mean RMS values of the knee and other locations of reference electrodes in the supine position, as well as between mean RMS values in all regions except the thigh and gluteus in the sitting position. The minimum mean RMS values in both positions were obtained with the reference electrode on the knee. Conclusions During urodynamic studies, reference electrodes shall be placed on AIS in the sitting and on the inner thigh in the supine position. The knee is not a suitable option for reference electrode placement. This information may help improve EMG recordings in the evaluation of pelvic floor muscles.

Abstract Reference electrodes (REs) play a crucial role in the accurate assessment and control of battery potentials, but their confidence is overestimated. Researchers have tracked the source of the error to the RE design that blocks the lithium‐ion path between anode and cathode. These errors or potential deviations are mostly modeled or less‐frequently estimated after observing Li plating post‐mortem. This is the first study to showcase an experimental method that allows a more precise error quantification in‐operando of a RE. The key idea is to relate the error‐affected reference potential to an unaffected quantity, such as the cell dilatation. Although our experimental setups are special, this approach can also be applied to different setups and REs. Using the presented method, we provoked Li plating in NMC811/graphite pouch cells and determined the potential deviation of our perforated RE to be 12 mV under fast charging conditions. In contrast to previous studies, we found the error to be positive, offering a new explanation of the error mechanism of REs.

Owing to their unique advantages, single‐electrode triboelectric nanogenerators (SETENGs) have gained wide attention and have been applied in myriad areas, especially in the burgeoning flexible/wearable electronics. However, there is still a lack of a clear understanding of SETENGs. For example, previous simulation models generally put the reference electrode perpendicularly below the working part, but in practice, the reference electrode is designed in various scenarios and noticeable differences in outputs often occur when the reference electrode changes. With SETENGs developing towards wearability and portability, its reference electrode is often required to be constructed inside the device. Consequently, to achieve optimum performance, it is essential to understand the reference electrode's influence on the outputs. Here, the influence of the reference electrode on the performance of SETENGs is systematically investigated and the targeted optimization strategies are thoroughly revealed. First, theoretical simulations are conducted to investigate the reference electrode's effect on the performance of SETENGs with different structures and in various working modes. Secondly, the theoretical results are certified through corresponding experiments. Based on the results, the targeted optimization strategies for SETENGs are comprehensively demonstrated. This work provides fundamental guidance for the development of TENGs and the design and fabrication of new electronic devices. [ABSTRACT FROM AUTHOR]

Definition: A reference electrode is a half-cell (an electrode) with a stable, well-defined and highly reproducible electrode potential. A vast number of electrodes have been developed for different applications. They are briefly presented. For the common types, the advantages and drawbacks are discussed. Practical hints for daily use are provided. [ABSTRACT FROM AUTHOR]

Organic light-emitting diodes (OLEDs) are a prominent display technology, yet the accurate characterization of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels in their constituent materials remains challenging. This study introduces a novel integrated reference-counter electrode (IRCE) assembly, leveraging a gel polymer electrolyte with an embedded silver quasi-reference electrode, facilitating the electrochemical measurement of HOMO and LUMO levels in small molecular thin-film semiconductors. Calibration of the IRCE against ferrocene enables the establishment of an absolute energy scale. Comparative stability tests against a standard Ag/AgNO 3 reference electrode confirm the IRCE's reliability. Electrochemical characterization using cyclic voltammetry was performed on prototypical OLED materials, including NPB, TCTA, PO-T2T neat films, and an NPB:PO-T2T exciplex film. While NPB and PO-T2T exhibited stable voltammograms, TCTA showed signs of electropolymerization. Additionally, the HOMO level of the NPB:PO-T2T exciplex was slightly shifted compared to that of NPB, suggesting interactions within the exciplex. The results demonstrated the IRCE's capability to accurately determine frontier energy levels in thin films, paving the way for better device modeling and a better understanding of underlying electronic processes in organic semiconductors. [Display omitted] 1. Introduced a novel electrolyte/reference electrode assembly, referred to as IRCE. 2. Calibrated IRCE against ferrocene for an absolute energy scale. 3. IRCE shows stability similar to Ag/AgNO 3 reference electrode. 4. IRCE enables electrochemical characterization of small-molecule thin film organic semiconductors. 5. Demonstrated electrochemical characterization of HOMO/LUMO levels in OLED materials. [ABSTRACT FROM AUTHOR]

Drift has been a problem for rumen pH sensors, but it is not known whether the reference electrode or the indicating electrode of the pH sensor is the main cause of the drift. In this study, the drift of each electrode was evaluated by placing pH sensors in a cow's rumen and temporarily removing them at intervals over a four-month period. Our experiment revealed that the drift of the indicating electrode caused by changes in sensitivity is the critical drift issue in realizing a stable rumen pH sensor, although the drift is caused by both the reference electrode and the indicating electrode. The sensitivity of the indicating electrode was around 57.0 mV/pH unit at the start of the experiment but dropped to 37.1 and 49.0 mV/pH unit for Cowl and Cow2, respectively, after placing the pH sensors in the rumen for four months. By assuming a change in the rumen's pH of around 2 pH units, the maximum drift caused by the indicating electrode appears to be 0.68 pH unit. From the observation of the indicating electrode, we found that the drift was caused by impurities on the glass surfaces, and the pH sensitivity was recovered by removing these impurities. Because the glass electrode cannot be cleaned when in the cow's rumen, the development of a glass electrode with resistance to impurities is required for rumen pH sensors. [ABSTRACT FROM AUTHOR]

Ion-sensitive field-effect transistors (ISFETs) detect specific ions in solutions that enable straightforward, fast, and inexpensive sensors compared to other benchtop equipment. However, a conventional reference electrode (RE) such as Ag/AgCl is limited on the miniaturization of the sensor. We introduce reduced graphene oxide (rGO), which serves as a new RE, when fluorinated (F-rGO) using fluorothiophenol through the π–π interaction. The circular RE is integrated between a fabricated microscale two-channel ISFET, which is capable of detecting two kinds of ions on an indium tin oxide (ITO) thin-film substrate, using the photolithography process. F-rGO bound to this circular region to function as an RE in the ISFETs sensor, which operated stably in solution and showed a relatively high transconductance (gm) value (1.27 mS), low drift characteristic (3.2 mV), and low hysteresis voltage (±0.05 mV). It detected proton (H+) ions in a buffer solution with high sensitivity (67.1 mV/pH). We successfully detected Na+ (62.1 mV/dec) and K+ (57.6 mV/dec) ions in human patient urine using a two-channel ISFET with the F-rGO RE. The F-rGO RE will be a suitable component in the fabrication of low-cost, mass-produced, and disposable ISFETs sensors. [ABSTRACT FROM AUTHOR]

The reference electrode's performance is essential for ensuring the accuracy of electrochemical sensors in marine environments. Yet, the many existing reference electrodes can exhibit sensitivity to salinity variations, potentially leading to inaccuracies in the measurement process. Herein, we have designed a reliable solid-state reference electrode by introducing SiO x -stabilized 1-methyl-3-octylimidazolium bis(trifluoromethyl sulfonyl)imide ([C 8 mim + ] [Ntf 2 - ]) into a P(VdF- co -HFP) matrix with a SPEEK/[C 8 mim + ] [Ntf 2 - ] coated Ag/AgCl as substrate. The SPEEK/[C 8 mim + improves the compatibility of the IL with the polymer matrix, thereby increasing the electrode's resistance to interference and extending its long-term stability and lifespan. The developed reference electrode showed a stable and rapid response, with potential variations of less than 0.7 mV across various salinity solutions, including practical seawater, lake water, and their mixture samples. During extended periods of 18 days in deionized water and artificial seawater, the electrode demonstrated negligible potential drifts of 0.36 and 0.14 mV/d, respectively. Notably, the electrode could maintain a stable potential even after being stored in a preservative solution for 67 days. Furthermore, the electrode showed a stable response to withstand pressures of up to 100 MPa, covering the vast majority of the seafloor. This innovative reference electrode is capable of maintaining a stable reference potential across various salinities, ionic strength, and full ocean depth, making it versatile for use in diverse aquatic environments, underscoring its significant potential for advancing oceanographic research and enabling new insights into the unexplored depths of oceans.2 - ] coating protects the AgCl substrate, and the incorporation of SiO x improves the compatibility of the IL with the polymer matrix, thereby increasing the electrode's resistance to interference and extending its long-term stability and lifespan. The developed reference electrode showed a stable and rapid response, with potential variations of less than 0.7 mV across various salinity solutions, including practical seawater, lake water, and their mixture samples. During extended periods of 18 days in deionized water and artificial seawater, the electrode demonstrated negligible potential drifts of 0.36 and 0.14 mV/d, respectively. Notably, the electrode could maintain a stable potential even after being stored in a preservative solution for 67 days. Furthermore, the electrode showed a stable response to withstand pressures of up to 100 MPa, covering the vast majority of the seafloor. This innovative reference electrode is capable of maintaining a stable reference potential across various salinities, ionic strength, and full ocean depth, making it versatile for use in diverse aquatic environments, underscoring its significant potential for advancing oceanographic research and enabling new insights into the unexplored depths of oceans.

Abstract Cell design is effective to improve the performances of lithium‐ion batteries (LIBs). For identifying the bottleneck of a full battery used for high‐rate charging/discharging, we developed a simple method, by a reference electrode in practical pouch cells, to quick obtain the polarizations of the cathode and the anode. For a Li(Ni0.6Co0.2Mn0.2)O2/graphite full cell, 63.9% and 97.0% of the polarizations originate from the anode at 50% state of charge (SOC) during 2.0 C charging and discharging rates, respectively. While for LiFePO4/graphite system, 62.5% and 55.8% of the polarizations originate from the anode at the same charging and discharging conditions. These indicate that the anode is the limitation during fast charging/discharging, which is consistent with the common understanding but in contrary to the results obtained by coin cells reported previously. While the rate limitation from anode in LiFePO4/graphite system during fast charging/discharging is significantly changed to both cathode and anode compared with Li(Ni0.6Co0.2Mn0.2)O2/graphite. Besides, graphite anodes in LiFePO4/graphite cells more readily dive to the Li‐metal plating potential at high charging rate. This leads to safety concerns of LiFePO4/graphite cells during fast charging. This is a facile strategy for fast distinguishing polarizations from cathodes and anodes of high‐rate LIBs.

Purpose: Perineal electromyography (EMG) is a crucial part of urodynamic studies. Many researchers focused on the standardization of techniques in urodynamics, but no study has yet evaluated the differences with various reference electrode placements. The aim of this study was to determine the optimal placement of the reference electrode for recording pelvic floor activity in urodynamic studies. Methods: Children over 6 years of age without anatomic or neurological abnormalities were invited to participate in the study. Four reference electrodes were placed on the right kneecap, the inner surface of the right inner thigh, the right anterior iliac spine (AIS), and the skin over the left gluteal muscles for simultaneous recording. The EMG signal formed by pelvic contraction during forceful straining was recorded both in the supine and sitting positions. The root mean square (RMS) value of each muscle contraction signal was calculated. Results: Twenty-one participants (10 boys and 11 girls) were included. The mean age was 10.19±3.20 years. The highest RMS values were obtained with the reference electrode on the thigh in the supine position and the AIS in the sitting position. Significant differences were found between the mean RMS values of the knee and other locations of reference electrodes in the supine position, as well as between mean RMS values in all regions except the thigh and gluteus in the sitting position. The minimum mean RMS values in both positions were obtained with the reference electrode on the knee. Conclusions: During urodynamic studies, reference electrodes shall be placed on AIS in the sitting and on the inner thigh in the supine position. The knee is not a suitable option for reference electrode placement. This information may help improve EMG recordings in the evaluation of pelvic floor muscles. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electrochemical aptamer-based sensors offer reagent-free and continuous analyte measurement but often suffer from poor longevity and potential drift even with a robust 3-electrode system. Presented here is a simple, software-enabled approach that tracks the redox-reporter peak in an electrochemical aptamer-based sensor and uses the measurement of redox peak potential to reduce the scanning window to a partial measure of redox-peak-height vs. baseline (~10X reduction in voltage range). This same measurement further creates a virtual reference standard in buffered biofluids such as blood and interstitial fluid, thereby eliminating the effects of potential drift and the need for a reference electrode. The software intelligently tracks voltammogram peak potential via the inflection points of the rising and falling slopes of the measured redox peak. Peak-tracking-derived partial scanning was validated over several days and minimized electrochemically induced signal loss to <5%. Furthermore, the peak-tracking approach was shown to be robust against confounding effects such as fouling. From an applied perspective in creating wearable biosensors, the peak-tracking approach further enables use of a single implanted working electrode, while the counter/reference-electrode may utilize a simple gel-pad electrode on the surface of the skin, compared to implanting working, counter, and reference electrodes conventionally used for stability and reliability but is also costly and invasive. Cumulatively, peak-tracking provides multiple leaps forward required for practical molecular monitoring by extending sensor longevity, eliminating potential drift, simplifying biosensor device construction, and in vivo placement for any redox-mediated sensor that forms parabolic-like data. [ABSTRACT FROM AUTHOR]

The use of a reference electrode and the analysis of Electrochemical Impedance Spectroscopy (EIS) data recorded in three-electrode configuration are beneficial for understanding the underlying electrochemical reaction mechanisms in Li-ion batteries. However, analysis of EIS data recorded both in two-electrode and especially three-electrode configurations is prone to misinterpretation due to presence of unidentified artifacts. Using the commercially available instrument (Biologic VMP3), EIS data is recorded simultaneously for both working and counter electrodes in three-electrode five-wire configuration and are algebraically summed to obtain the data for two-electrode configuration. This data is then compared to that recorded in two-electrode configuration. This arrangement of instrument helps in identifying the otherwise hidden and anomalous features, such as a high-frequency arc and extended solid electrolyte interphase (SEI) region, in the three-electrode configuration and the reason for their absence in the two-electrode configuration. Moreover, these additional features are found State-of-Charge (SoC) i.e., cell-electrochemistry dependent and can be highly influenced by the resistance of current/potential measuring leads. Additionally, a new methodology is established to rectify the EIS data and obtain 'artifact-free' electrochemical data. [Display omitted] [ABSTRACT FROM AUTHOR]

Greener alternatives for high demand materials is becoming increasingly necessary. Conductive screen printable ink formulations are vital components of sensors, e.g., for glucose monitoring in diabetics, and printable electronics. Here, the formulation of a reliable, low-cost, high-performance and greener alternative of an Ag/AgCl screen-printable ink formulation is reported. The ink formulation has a significantly lower silver nanoparticle loading, 25 %, is based on a nontoxic organic solvent and uses a biodegradable polymeric mixture of polyhydroxyether/polyether resin (ratio of 1:2). The cytotoxicity of the Carbon/Ag/AgCl Ref SPE was evaluated and compared to screen-printed electrodes based on a commercial ink formulation. The Carbon/Ag/AgCl Reference screen printed electrodes (Carbon/Ag/AgCl Ref SPE) demonstrated good reproducibility, high analytical performance (RSD% 2.45) and the reference potential is highly stable in the electrochemical detection of glucose using a commercial glucose meter. [Display omitted] [ABSTRACT FROM AUTHOR]

In teaching and research the hydrogen electrode is indispensable. In the conventional design pressurized hydrogen is needed, this possibly limits practical use. Starting with the concept of a hydrogen electrode operating without an external hydrogen supply keeping nevertheless all advantages of a conventional hydrogen electrode we demonstrate, that popular lab course experiments are correctly done with this electrode. [ABSTRACT FROM AUTHOR]

The electrical and chemical properties of the titanium dioxide (TiO2) coated spirals grown by the atomic layer deposition (ALD) technique in two different temperatures of 150 °C and 300 °C are studied. The thickness of the TiO2 layers studied are 20, 40, and 80 nm. A switched capacitor amplifier is used to investigate the pH response and the capacitance of the samples. It is found that the performance of the TiO2 samples depends on either the thickness or the deposition temperature due to the differences in the physical properties of the oxide layer such as surface roughness and film density. The high temperature samples are more crystalline, whereas the low temperature samples are more amorphous. Since there is a low pass filter effect in the electrolyte–sample interface, the TiO2 coated samples show the better response to the pH change for the high temperature samples as the sensor surface area for binding the hydrogen ions is larger and the charge transfer resistance is smaller. Furthermore, more roughness on the surface can be obtained by increasing the thickness, which reduces the charge transfer resistance. In this study, the 80 nm sample deposited at 300 °C gives the best pH response of 40 mV/pH. [ABSTRACT FROM AUTHOR]

The silver nanoparticle (AgNP) ink synthesized was simple, well-dispersed, did not need sintering, had excellent conductivity and can be used as a conductive ink in several areas, particularly in the fabrication of reference electrodes. The AgNP ink was fabricated by synthesizing AgNP using the polyol method and then dispersing in methanol to fabricate the conductive ink. The synthesis was explained step-by-step, the proposed mechanism was discussed and photos of the entire process were shown. The materials (AgNO3 and AgNP) were characterized by UV–Vis, SEM and XRD. The UV–Vis exhibit a strong broad peak at 417 nm due the surface plasmon resonance (SPR) absorption band of AgNP. The SEM images showed spherical nanoparticles, non-aggregates and with an average diameter of 50 - 140 nm. The XRD of AgNP presented four main characteristic peaks for silver corresponding to (111), (200), (220) and (311) planes, confirming the cubic (FCC) silver. The AgNP ink has an excellent conductivity, with an average ohmic resistance of 1.53 Ω. Finally, the AgNP ink was tested in the fabrication of reference electrodes and the analytical response was higher than the conventional Ag/AgCl reference electrode.

To miniaturize or integrate electrochemical devices, new types of nanoparticle-based Ag/AgCl quasi-reference electrodes (qREs) have been generated via screen printing and inkjet printing. However, their nanostructures and addition of binder materials produce unsatisfactory conductivity and sensitivity. Herein, a novel Ag/AgCl qRE with a nanowire-and-nanoparticle (NWP) structure is developed. The unique NWP-Ag/AgCl qRE is first generated by drop coating silver nanowires (AgNWs) on poly(dimethylsiloxane) (PDMS), followed by chemical chlorination. Because the nanowires form well-connected network, the novel NWP-Ag/AgCl qRE creates efficient charge transport paths as well as porous 3D structures that enable faster electrolyte percolation. The NWP-Ag/AgCl qRE reaches 95% stable potential fast (6.4 s) and is extremely stable (at least 8000 s continuous measurement and 6-month shelf life). The NWP-Ag/AgCl qRE on PDMS provides ultracomfortable tactile experience that is suitable for skin-contact electrophysiology. The NWP-Ag/AgCl qRE has also been successfully applied to the detection of glucose with a linear range of 1 μM–1900 μM. This study establishes a new printer-free Ag/AgCl qRE fabrication method with simple chemistry. Furthermore, the new method is a truly transformatively efficient and cost-effective approach with substantial industrial applications to electrophysiology and electrochemical device-making.