Search

This paper reports the ability of chitosan-reduced graphene oxide (rGO) modified electrode as a sensitive layer of working electrode in detecting formaldehyde. The electrode substrate is in the form of copper-SPE which has been shaped into 5 mm of sensitive area. On top of the working electrode, a number of chitosan and chitosan-reduced graphene oxide (rGO) matrices were placed in the form of a thin film layer that works as a working electrode. Characterization of chitosan and chitosan-reduced graphene oxide (rGO) thin films was done using SEM, TEM, AFM and FTIR. The test for electrochemical sensing ability of working electrode was observed using cyclic voltammetry (CV), whereas chitosan and chitosan-rGO films were deposited onto the surface of working electrodes. The novelty of this research is the utilization of chitosan-rGO thin film based working electrode for detecting formaldehyde. The testing results showed sensitivity and response of working electrode increased when chitosan-reduced graphene oxide modified electrode was used for formaldehyde detection compared to chitosan film based working electrode. It was proven from the sensitivity value of chitosan-rGO based working electrode at the lowest value of 4.6 × 10−4 µA/µM and linear range at 1–12 × 10−4 µM/L, as well as the ability of chitosan-rGO based working electrode which worked at limit of detection (LoD) 0.36 µM/L and limit of quantification (LoQ) 1.21 µM/L.

The technological advancement relevant to energy storage devices are paramount considering the energy demand that will substantially increase in the future. Although electrodes are playing an essential role in these devices, the novel electrode technology carries a significant weight that can produce colossal impact on energy storage applications. The present study describe the advancement of graphite-clay composite electrodes, improving properties and performance by incorporating additional materials, which results in a quaternary electrode that is not only succeeded in energy storage but also in electroanalytical applications. The mechanical compression and thermal activation are the only technological processing steps that employed in fabricating quaternary composite electrode, which consists of graphite, colloidal graphite, kaolinite and cement (GCGKCeCE). The ideal voltammogram signal with higher sensitivity to both Fe2+ and Fe3+, which are 1.01 A m mol−1 and 1.07 A m mol−1, respectively, than the commercial electrodes is well-noticeable with GCGKCeCE, indicating better analyte detection ability. Aniline electropolymerization on GCGKCeCE led to PANI-GCGKCeCE that has low interface (0.30 Ω) and charge transfer (0.46 Ω) resistance due to a unique interwoven nanofiber network consisting of villi-like surface projections, which resulted from synergistic interactions between GCGKCeCE and PANI. The supercapacitor cell fabricated with an identical PANI-GCGKCeCE account for very high specific capacitance, which is 1029 F g−1 at 5 mV s−1, confirming the feasibility in energy storage applications. The 99% coulombic efficiency that observed with supercapacitor cell even after 1800 cycles indicates an improved cyclic stability, which ensures better reversibility and lifespan. [ABSTRACT FROM AUTHOR]

Nitrogen electrofixation under ambient conditions is a promising approach to synthesize ammonia sustainably but improving the yield and efficiency remains a challenge. This is due to the competition between the nitrogen electrofixation and hydrogen evolution reactions, which can be depressed through appropriate working electrode design. This study investigated the influence of the catalyst‐binder configuration on ammonia yield and Faradic efficiency. A series of working electrodes were tested in an aqueous system, with the proton and electron transfer on the working electrode found to be dependent on the catalyst material, binder material, and binder hydrophobicity. The use of a binder with low proton/electron conductivity increased Faradic efficiency by hindering the hydrogen evolution reaction and reducing charge transfer to the catalytic material. Utilising a hydrophobic binder significantly improved ammonia yield. Furthermore, nitrogen sorption experiments revealed that the catalyst's nitrogen affinity exerts a greater influence on ammonia yield than the binder's affinity. The best performance was observed for a semi‐conductive catalyst based on vanadium, integrated within a highly hydrophobic perfluorinated binder. At ambient conditions in 0.1 M hydrogen chloride, 39.3±4.3 μgh-1mgcat.-1 ${\mu g{{\rm \ }h}^{-1}{\rm \ }{mg}_{cat.}^{-1}}$ of ammonia was synthesized with 38.5±4.5 % Faradic efficiency at −0.2 V versus a reversible hydrogen electrode. [ABSTRACT FROM AUTHOR]

Abstract Nitrogen electrofixation under ambient conditions is a promising approach to synthesize ammonia sustainably but improving the yield and efficiency remains a challenge. This is due to the competition between the nitrogen electrofixation and hydrogen evolution reactions, which can be depressed through appropriate working electrode design. This study investigated the influence of the catalyst‐binder configuration on ammonia yield and Faradic efficiency. A series of working electrodes were tested in an aqueous system, with the proton and electron transfer on the working electrode found to be dependent on the catalyst material, binder material, and binder hydrophobicity. The use of a binder with low proton/electron conductivity increased Faradic efficiency by hindering the hydrogen evolution reaction and reducing charge transfer to the catalytic material. Utilising a hydrophobic binder significantly improved ammonia yield. Furthermore, nitrogen sorption experiments revealed that the catalyst‘s nitrogen affinity exerts a greater influence on ammonia yield than the binder‘s affinity. The best performance was observed for a semi‐conductive catalyst based on vanadium, integrated within a highly hydrophobic perfluorinated binder. At ambient conditions in 0.1 M hydrogen chloride, 39.3±4.3 μgh-1mgcat.-1 of ammonia was synthesized with 38.5±4.5 % Faradic efficiency at −0.2 V versus a reversible hydrogen electrode.

Permissible limits of Pb2+ in drinking water are being reduced from 10 μgL−1 to 5 μgL−1, which calls for rapid, and highly reliable detection techniques. Electrochemical sensors have garnered attention in detection of heavy metal ions in environmental samples due to their ease of operation, low cost, and rapid detection responses. Selectivity, sensitivity and detection capabilities of these sensors, can be enhanced by modifying their working electrodes (WEs) with iron oxide nanoparticles (IONPs) and/or their composites. Therefore, this review is an in-depth analysis of the deployment of IONPs/nanocomposites in modification of electrochemical sensors for detection of Pb2+ in drinking water over the past decade. From the analyzed studies (n = 23), the optimal solution pH, deposition potential, and deposition time ranged between 3 and 5.6, −0.7 to −1.4 V vs Ag/AgCl, and 100–400 s, respectively. Majority of the studies employed square wave anodic stripping voltammetry (n = 16), in 0.1 M acetate buffer solution (n = 19) for detection of Pb2+. Limits of detection obtained (2.5 x 10−9 - 4.5 μg/L) were below the permissible levels which indicated good sensitivities of the modified electrodes. Despite the great performance of these modified electrodes, the primary source of IONPs has always been commercial iron-based salts in addition to the use of so many materials as modifying agents of these IONPs. This may limit reproducibility and sustainability of the WEs due to lengthy and costly preparation protocols. Steel and/or iron industrial wastes can be alternatively employed in generation of IONPs for modification of electrochemical sensors. Additionally, biomass-based activated carbons enriched with surface functional groups are also used in modification of bare IONPs, and subsequently bare electrodes. However, these two areas still need to be fully explored.

This paper presents an overview of approaches proposed in the scientific literature for the voltammetric determination of rare earth elements (mainly cerium and europium individually, as well as various lanthanides simultaneously) in manifold kinds of samples. The work is divided into chapters describing the most important aspects affecting the sensitivity of the proposed methods: the technique adopted (AdSV, ASV, CSV), complexing agents used, the kind of working electrode (mercury-based, noble metal or carbon electrodes) and the most popular electrode modifiers (e.g., metal film, carbon nanotubes, molecularly imprinted polymers). Analytical parameters of the procedures presented in the paper are collected in tables. The subsequent chapters are devoted to a detailed discussion of potential inorganic and organic interfering factors. The possibilities of simultaneous determination of several lanthanides in one sample and the influence of other lanthanides on the determined rare earth element were also discussed. Finally, the applications of the voltammetric procedures to the determination of rare earth metals in real samples with miscellaneous matrix is described. All analytical results were tabulated in order to compare the analytical suitability of the proposed procedures. [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.

Miniaturization of electrochemical components has become less common in the last decade, with the focus predominantly being the design and development of state-of-the-art microelectrodes for achieving small volume analysis of samples. However, such microelectrodes involve cumbersome processing procedures to convert the base material for the required application. A potential paradigm shift in such miniaturization could be achieved by using cheaper alternatives such as plastics to build electrochemical components, such as micropipette tips made of polypropylene, which are commercially available at ease. Hence, this work presents the design of an electrochemical working electrode based upon a micropipette tip, involving minimal processing procedures. Furthermore, such a working electrode was realized by sputtering silver onto a bare micropipette tip using a radio-frequency sputtering technique, to obtain electrical contacts on the tip, followed by hydrothermal growth of ZnO, which acted as the active electrode material. The ZnO nanostructures grown on the micropipette tip were characterized for their morphology and surface properties using a scanning electron microscope (SEM), laser microscope, Raman spectrometer, and X-ray photoelectron spectrometer (XPS). The developed micropipette tip-based electrode was then used as the working electrode in a three-electrode system, wherein its electrochemical stability and properties were analyzed using cyclic voltammetry (CV). Furthermore, the above system was used to detect glucose concentrations of 10–200 µM, to evaluate its sensing properties using amperometry. The developed working electrode exhibited a sensitivity of 69.02 µA/µM cm−2 and limit of detection of 67.5 µM, indicating the potential for using such modified micropipette tips as low-cost miniaturized sensors to detect various bio-analytes in sample solutions. [ABSTRACT FROM AUTHOR]

This paper presents an overview of approaches proposed in the scientific literature for the voltammetric determination of rare earth elements (mainly cerium and europium individually, as well as various lanthanides simultaneously) in manifold kinds of samples. The work is divided into chapters describing the most important aspects affecting the sensitivity of the proposed methods: the technique adopted (AdSV, ASV, CSV), complexing agents used, the kind of working electrode (mercury-based, noble metal or carbon electrodes) and the most popular electrode modifiers (e.g., metal film, carbon nanotubes, molecularly imprinted polymers). Analytical parameters of the procedures presented in the paper are collected in tables. The subsequent chapters are devoted to a detailed discussion of potential inorganic and organic interfering factors. The possibilities of simultaneous determination of several lanthanides in one sample and the influence of other lanthanides on the determined rare earth element were also discussed. Finally, the applications of the voltammetric procedures to the determination of rare earth metals in real samples with miscellaneous matrix is described. All analytical results were tabulated in order to compare the analytical suitability of the proposed procedures.

Glass pH sensors are unsuitable for in vivo biomedical, clinical, or food applications because of the brittleness of glass and the difficulty in measuring small volumes. Enamel structures such as glass/stainless steel are candidates for glass-based pH electrodes. In this study, new enamel electrodes for pH sensors using Fe2O3–TeO2-based glass/stainless steel were developed. The effect of NiO addition to Fe2O3–TeO2 glass on the pH sensitivity and the three-point bending strength of enamels were investigated. The effect of NiO addition to Fe2O3–TeO2 glass/stainless steel on the pH sensitivity was negligible. Fe2O3–TeO2-based glass/stainless steel showed pH sensitivity appropriate to a working electrode. Enameling at a lower temperature under an air atmosphere was desirable for narrowing the gap between pH 4–7 and pH 7–9 sensitivities. The NiO addition to Fe2O3–TeO2 glass/stainless steel decreased the three-point bending strength. Therefore, NiO did not serve as an adhesion oxide in the Fe2O3–TeO2 glass. Fe2O3–TeO2 glass/stainless steel possessed the highest three-point bending strength among all samples when prepared at 670 °C under an air atmosphere. Therefore, no NiO addition and enameling at a lower temperature under an air atmosphere are desirable for obtaining more robust Fe2O3–TeO2 glass/stainless steel than Li2O–SiO2-based glass electrodes for pH sensors.

This work demonstrates the fabrication of a binder-free ternary graphite-clay-cement composite electrode (GKCeCE) with improved electrical/mechanical properties and its potential electrochemical applications as an ideal working electrode. The combination of clay and cement (~ 5%) accounts for a sturdy lamella-like graphite structure, which is responsible for improved electrical conductivity and mechanical strength of GKCeCE. GKCeCE can produce an ideal cyclic voltammetry signal with narrow peak-to-peak separation, avoiding high background current and peak broadening characteristics to binary composite electrodes. The aniline can be successfully electropolymerized with GKCeCE. The polyaniline deposited on GKCeCE consists of a nanofiber network, exhibiting the lowest serial (10 Ω) and charge transfer resistance (77.5 Ω), indicating the potential of modified GKCeCE in the fabrication of various electrochemical devices and sensors. GKCeCE is a low-cost improved version of the binder-free composite of graphite that is considered a potential alternative for expensive commercial working electrodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Band gap tuned BaS 2 :Cu 8 S 5 :LaS trichalcogenide system. • Significant functionality as energy material. • BaS 2 :Cu 8 S 5 :LaS embellished nickel foam electrode. • Charge storage of 1299F/g specific capacitance. • Specific power density of 11166 W kg−1. • Excellent durability and stability. Current work, for the first time, reports the synthesis of the novel BaS 2 :Cu 8 S 5 :LaS ternary chalcogenide for utilization in the energy storage devices owing to its superior capacitive performance. BaS 2 :Cu 8 S 5 :LaS was marked by remarkable optical behavior with the narrowed band gap energy i.e. 2.55 eV. Crystallographic analysis is indicative of the 16.77 nm average crystallite size. The presence of the metal sulphide bonds was confirmed by the vibrational stretches between 420 – 890 cm−1. Rod shaped particles with the suspended spheres was the predominant morphology. With the augmented redox behavior and charging-discharging behavior, fabricated electrode attained the auspicious specific capacitance of 1299F/g. Furthermore, the specific power density obtained for this electrode was 11166 W kg−1. The enhanced electrochemical performance was also exhibited by the elevated electrical conductivity showing the equivalent series resistance (R s) = 0.48 Ω. [ABSTRACT FROM AUTHOR]

Miniaturization of electrochemical components has become less common in the last decade, with the focus predominantly being the design and development of state-of-the-art microelectrodes for achieving small volume analysis of samples. However, such microelectrodes involve cumbersome processing procedures to convert the base material for the required application. A potential paradigm shift in such miniaturization could be achieved by using cheaper alternatives such as plastics to build electrochemical components, such as micropipette tips made of polypropylene, which are commercially available at ease. Hence, this work presents the design of an electrochemical working electrode based upon a micropipette tip, involving minimal processing procedures. Furthermore, such a working electrode was realized by sputtering silver onto a bare micropipette tip using a radio-frequency sputtering technique, to obtain electrical contacts on the tip, followed by hydrothermal growth of ZnO, which acted as the active electrode material. The ZnO nanostructures grown on the micropipette tip were characterized for their morphology and surface properties using a scanning electron microscope (SEM), laser microscope, Raman spectrometer, and X-ray photoelectron spectrometer (XPS). The developed micropipette tip-based electrode was then used as the working electrode in a three-electrode system, wherein its electrochemical stability and properties were analyzed using cyclic voltammetry (CV). Furthermore, the above system was used to detect glucose concentrations of 10–200 µM, to evaluate its sensing properties using amperometry. The developed working electrode exhibited a sensitivity of 69.02 µA/µM cm−2 and limit of detection of 67.5 µM, indicating the potential for using such modified micropipette tips as low-cost miniaturized sensors to detect various bio-analytes in sample solutions.

This review highlights and summarizes the impact of different fabrication processes on the efficiency of dye-sensitized solar cells (DSSCs). Energy conversion efficiency of cell depends upon semiconductor, sensitizer, electrolyte, and counter electrode. Efficiency of DSSCs can be enhanced by properly selecting the optimum significance of various parameters of fabrications process. Major challenges of these solar cells are non-vegetal, noxious, extreme sensitizers. Application of natural dyes in this field plays a significant role. An optimized CdSe-TiO2 photoanode showed a power conversion efficiency (PCE) of 13.29% and short circuit current density of 15.30 mA cm−2 for the DSSC. Power conversion efficiency of 3.26% was achieved by using TTO electrode for DSSC device that is ascribed to the improved electrical and optical properties due to doping with Ta element. Absorbance of betalain was shown in the visible range of 530–535 nm for betanin while 450–559 nm for anthocyanin pigment. The natural dyes are economical, readily available, and environmentally friendly. This compilation would be beneficial for researchers working on dye solar cell. [ABSTRACT FROM AUTHOR]

In this paper extract of pomegranate, beet root and black berry are used to study the performance of these dyes on the DSSCs. The UV‐vis spectra of natural dyes suggest that pomegranate and blackberry have a better absorptive capacity at 300–550 nm, which is attributed to higher concentration of pigment with anthocyanin. From the overall study of natural dyes, it is observed that the blackberry exhibits optimal performance and power conversion efficiency reaches up to 0.160% due to higher absorption coefficient as compared to other natural dyes under study. [ABSTRACT FROM AUTHOR]

Efficient extraction of Li from brine at a low cost is becoming a key technology to solve energy and environmental problems. Electrochemical extraction of Li has become a research hotspot due to its low energy consumption, high selectivity, and environmental friendliness. LiMn2O4, LiFePO4, and LiNi1/3Co1/3Mn1/3O2 are widely used as cathode materials for the electrochemical extraction of Li but they also have some drawbacks, such as a small adsorption capacity. In this paper, the principle of electrochemical Li extraction from brine is reviewed and the research progress and analysis of the above three working electrode materials is summarized. In addition, analysis of the extraction of other rare ions from the working electrode material and the effect of micro-organisms on the working electrode material is also presented. Next, the shortcomings of working electrode materials are expounded upon and the research direction of working electrode materials in electrochemical Li extraction technology are prospected. It is hoped that this paper can provide insights and guidance for the research and application of electrochemical Li extraction from brine.

Permissible limits of Pb 2+ in drinking water are being reduced from 10 μgL -1 to 5 μgL -1 , which calls for rapid, and highly reliable detection techniques. Electrochemical sensors have garnered attention in detection of heavy metal ions in environmental samples due to their ease of operation, low cost, and rapid detection responses. Selectivity, sensitivity and detection capabilities of these sensors, can be enhanced by modifying their working electrodes (WEs) with iron oxide nanoparticles (IONPs) and/or their composites. Therefore, this review is an in-depth analysis of the deployment of IONPs/nanocomposites in modification of electrochemical sensors for detection of Pb 2+ in drinking water over the past decade. From the analyzed studies (n = 23), the optimal solution pH, deposition potential, and deposition time ranged between 3 and 5.6, -0.7 to -1.4 V vs Ag/AgCl, and 100-400 s, respectively. Majority of the studies employed square wave anodic stripping voltammetry (n = 16), in 0.1 M acetate buffer solution (n = 19) for detection of Pb 2+ . Limits of detection obtained (2.5 x 10 -9 - 4.5 μg/L) were below the permissible levels which indicated good sensitivities of the modified electrodes. Despite the great performance of these modified electrodes, the primary source of IONPs has always been commercial iron-based salts in addition to the use of so many materials as modifying agents of these IONPs. This may limit reproducibility and sustainability of the WEs due to lengthy and costly preparation protocols. Steel and/or iron industrial wastes can be alternatively employed in generation of IONPs for modification of electrochemical sensors. Additionally, biomass-based activated carbons enriched with surface functional groups are also used in modification of bare IONPs, and subsequently bare electrodes. However, these two areas still need to be fully explored., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

The working electrode's surface property is crucial to cell adhesion and signal collection in electric cell-substrate impedance sensing (ECIS). To date, the indium tin oxide (ITO)-based working electrode is of interest in ECIS study due to its high transparency and biocompatibility. Of great concern is the impedance signal loss, distortion, and data interpretation conflict profoundly created by the movement of multiple cells during ECIS study. Here, a carboxyl-terminated ITO substrate was prepared by stepwise surface amino silanization, with N-hydroxy succinimide (NHS) and 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) treatment, respectively. We investigated the stepwise changes in the property of the treated ITO, cell-substrate adhesion, collective cell mobility, and time course of change in absolute impedance from multiple Chinese hamster ovary (CHO) cells [(Dt-DjZj)CELLS]. The carboxyl-terminated ITO substrate with a surface roughness of 6.37nm shows enhanced conductivity, 75% visible light transparency, improved cell adherence, reduced collective cell migration speed by approximately twofold, and diminished signal distortion in the [(Dt-DjZj)CELLS]. Thus, our study provides an ITO surface-treatment strategy to reduce multiple cell movement effects and to obtain essential cell information from the ECIS study of multiple cells through undistorted (Dt-DjZj)CELLS. [ABSTRACT FROM AUTHOR]

In the recent years, researchers from all over the world have become interested in the fabrication of advanced and innovative electrochemical and/or biosensors for respiratory virus detection with the use of nanotechnology. These fabricated sensors demonstrated a number of benefits, including precision, affordability, accessibility, and miniaturization which makes them a promising test method for point-of-care (PoC) screening for SARS-CoV-2 viral infection. In order to comprehend the principles of electrochemical sensing and the role of various types of sensing interfaces, we comprehensively explored the underlying principles of electroanalytical methods and terminologies related to it in this review. In addition, it is addressed how to fabricate electrochemical sensing devices incorporating nanomaterials as graphene, metal/metal oxides, metal organic frameworks (MOFs), MXenes, quantum dots, and polymers. We took an effort to carefully compile current developments, advantages, drawbacks, possible solutions in nanomaterials based electrochemical sensors. [Display omitted] • An overview of the SARS-CoV-2 sensor fabrication using the advanced electroanalytical techniques. • The function and importance of the working/indicator electrode was carefully analyzed. • Electroanalytical technique steps are critically discussed. • Electrochemistry's challenges and future potentials in building SARS-CoV-2 sensing interfaces are extensively summarized. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bismuth oxybromide/reduced graphene oxide nanocomposite was solvothermally synthesized. • The addition of GO promotes the blooming flower like microsphere of BiOBr into unfurled flower like microspheres. • BiOBr/RGO electrode exhibits both battery (BiOBr) and EDLC (RGO) performances. • The obtained power density (1.15 kW/kg) and energy density (207 Wh/kg) are fall in the supercapattery region of the Ragone plot. • An ultrahigh specific capacity of 3254 C/g and capacity retention of 97% at 1000 cycles were attained. The present work deals with a synthesis and characterization of bismuth oxybromide decorated reduced graphene oxide (BiOBr/RGO) nanocomposite as working electrode for supercapattery applications. where solvothermal method was adopted for the preparation of BiOBr/RGO nanocomposite. The prepared BiOBr depicts blooming flower-like microspheres and the presence of voids between petals could enable more adsorption of electrolyte ions and also act as conductive channels for easy ion diffusion. Further, the addition of GO with BiOBr resulted in an unfurling flower like morphology for BiOBr/RGO nanocomposite. The BiOBr/RGO (BiOBr – 3 wt% of GO) nanocomposite exhibits supreme specific capacity (C s) of 3254 C/g at 1 A/g, energy density of 207 Wh/kg at 1 A/g and cyclic stability of 1000 cycles with a capacity retention rate of 97%. These outstanding electrochemical performances suggest that the prepared BiOBr/RGO nanocomposite may serve as a promising working electrode for supercapattery applications in the near future. [ABSTRACT FROM AUTHOR]

Ternary metal nanocomposites were characterized using FT-IR, FE-SEM, UV–Vis, and X-ray diffraction (PXRD and GID) studies. Nanocomposite (Cu/Fe/NiO) modified working electrode was fabricated for voltammetric detection of Tartrazine dye in soft drink. A wide concentration range (0–500 µM) was used for the voltammetric sensing of Tartrazine dye. Voltammetric techniques like linear sweep voltammetry (LSV), differential pulse voltammetry (DPV), and cyclic voltammetry (CV) were used for the electrochemical characterization of dye. The sensor shows a good electrochemical oxidation peak in 0.1 M sodium phosphate buffer solution (pH 6.0) as supporting electrolyte at a scan rate of 0.01 mVs−1. Impedance spectroscopy (IS) technique was applied to examine the working electrode–electrolyte interface and film resistance. The effect of pH and scan rate on the electrochemical oxidation of Tartrazine was also examined. Lowest detection limit of Tartrazine was 0.06 µM. [Display omitted] • An efficient, quick and reliable voltammetric sensor was developed. • WE was modified using ternary metal oxide Nanocomposites. • CV, LSV, and DPV electrochemical techniques were used. • Tartrazine dye was detected in real and artificial food samples. Monitoring synthetic dyes in foodstuffs holds significant importance owing to their adverse effects on human health. A modified Sol-gel process was used for synthesizing mixed metal (Copper, Iron, and Nickel oxides) nanocomposites (NCs). Ternary metal NCs were characterized using FT-IR, FE-SEM, UV–Vis, and X-ray diffraction (PXRD and GID) studies. NCs (Cu/Fe/NiO) modified working electrode was fabricated for Voltammetric detection of Tartrazine dye in soft drinks. A wide concentration range (0–500 µM) was used for the Voltammetric sensing of Tartrazine dye. Voltammetric techniques like Linear Sweep Voltammetry (LSV), Differential Pulse Voltammetry (DPV), and Cyclic Voltammetry (CV) were used for the electrochemical characterization of dye. The sensor shows a good electrochemical oxidation peak in 0.1 M sodium phosphate buffer solution (pH 6.0) as a supporting electrolyte at a scan rate of 0.01 mV s−1. The impedance spectroscopy (IS) technique was applied to examine the working electrode–electrolyte interface and film resistance. A comparative study of the sensor was done with a bare glassy carbon electrode (GCE), and a Cu-wire electrode using the CV technique. The NCs modified working electrode shows a higher oxidative peak in comparison to bare GCE and Cu-wire electrodes for sensing dye. The effect of pH and scan rate on the electrochemical oxidation of Tartrazine was also examined. The lowest detection limit of Tartrazine was 0.010 µM. The fabricated working electrode shows high sensing capability for Tartrazine dye in natural and synthetic samples. The developed sensor proved to be cost-effective, and reliable for detecting food preservatives, additives, and coloring agents. [ABSTRACT FROM AUTHOR]

Observation of the dye-sensitised solar cell (DSSC) physical mechanism cannot be carried out experimentally; therefore, an analysis using a model is needed to explain the mechanism. In this article, DSSC is modelled as a series comprising a diode and other electronic components, including a photocurrent (Iph), saturation current (I0), series resistance (Rs), parallel resistance (Rp) and the ideality factor of the diode (n). These electronic components are called DSSC internal parameters. This study aims to find the value of DSSC internal parameters with variations of working electrode thickness. The particle swarm optimisation (PSO) algorithm as an optimisation method is used to achieve the aim. The model indicates that by increasing the thickness, the photocurrent rises and the parallel resistance decreases. [ABSTRACT FROM AUTHOR]

Metallic corrosion is a serious industrial problem due to its impact on economic losses and unavoidable structural damage. In this work, Ficus hispida leaf extract (FHLE) is employed in 1 M H2SO4 as a corrosion control agent on mild steel. FHLE effect on corrosion reduction of mild steel has been studied using non-electrochemical and electrochemical methods. From the experimental results, it is proved that the protection efficiency rises with increase in FHLE concentration and diminishes with increase in temperature. Tafel polarization plots suggest that FHLE prevents corrosion both anodic and cathodic area. The charge transfer resistance increased and the double-layer capacitance diminished when the FHLE concentration increased which is verified by AC impedance data. Various spectroscopic studies have affirmed the presence of a protective film on the electrode surfaces. [ABSTRACT FROM AUTHOR]

We developed a new approach to attach particles onto a conductive layer as a working electrode (WE) in a microfluidic electrochemical cell with three electrodes. Nafion, an efficient proton transfer molecule, is used to form a thin protection layer to secure particle electrodes. Spin coating is used to develop a thin and even layer of Nafion membrane. The effects of Nafion (5 wt% 20 wt%) and spinning rates were evaluated using multiple sets of replicates. The electrochemical performance of various devices was demonstrated. Additionally, the electrochemical performance of the devices is used to select and optimize fabrication conditions. The results show that a higher spinning rate and a lower Nafion concentration (5 wt%) induce a better performance, using cerium oxide (CeO2) particles as a testing model. The WE surfaces were characterized using atomic force microscopy (AFM), scanning electron microscopy-focused ion beam (SEM-FIB), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and X-ray photoelectron spectroscopy (XPS). The comparison between the pristine and corroded WE surfaces shows that Nafion is redistributed after potential is applied. Our results verify that Nafion membrane offers a reliable means to secure particles onto electrodes. Furthermore, the electrochemical performance is reliable and reproducible. Thus, this approach provides a new way to study more complex and challenging particles, such as uranium oxide, in the future.

Three-electrode system is universally utilized in lithium-ion batteries to study the reaction mechanism of working electrodes during the charge-discharge process. In all-solid-sate batteries, however, it cannot be easily used due to the practical constraints to the selection and placement of the reference electrode. We investigate the factors that influence capacity fade in all-solid-sate batteries consisting of Li2S-P2S5 electrolyte, Li4.4Si anode, and TiS2 cathode, with an embedded reference electrode. Ohmic resistance, charge transfer resistance, and polarization resistance are determined for each electrode using the embedded probe. The first discharge process is dominated by a low chemical diffusion coefficient of TiS2. The first charge capacity is reduced due to the relatively sluggish kinetics of the alloying process, which sequentially affects the next cycle performance. Diagnosis using the three-electrode setup reveals that the alloying process is a critical step in determining the performance of all-solid-sate batteries with alloy electrodes. [ABSTRACT FROM AUTHOR]

Electrochemical analysis is an efficient way to study various materials. However, nanoparticles are challenging due to the difficulty in fabricating a uniform electrode containing nanoparticles. We developed novel approaches to incorporate nanoparticles as a working electrode (WE) in a three-electrode microfluidic electrochemical cell. Specifically, conductive epoxy was used as a medium for direct application of nanoparticles onto the electrode surface. Three approaches in this work were illustrated, including sequence stamping, mix stamping, and droplet stamping. Shadow masking was used to form the conductive structure in the WE surface on a thin silicon nitride (SiN) membrane. Two types of nanomaterials, namely cerium oxide (CeO2) and graphite, were chosen as representative nanoparticles. The as-fabricated electrodes with attached particles were characterized using atomic force microscopy (AFM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Electrochemical analysis was performed to verify the feasibility of these nanoparticles as electrodes. Nanomaterials can be quickly assessed for their electrochemical properties using these new electrode fabrication methods in a microfluidic cell, offering a passport for rapid nanomaterial electrochemical analysis in the future.