Electrochemical Analysis Methods Research Articles

Physicochemical, Morphological and Anticorrosive Properties of Electrodeposited ZnNi Alloy Coating

Corrosion in its many forms is a major problem for many types of materials, extending from machining to manufacturing and daily use. In fact, it affects practically all engineering projects, from the biggest to the smallest: energy production, construction, transport, medical sector, electronics, etc. Consequently, corrosion generates both economic and environmental problems. To prevent corrosion and preserve materials' durability, several protection methods can be applied. These included protection by applying a coating on the metal surface. In this context, Zinc based alloy coatings have attracted much interesting scientific community because of their excellent mechanical and anti-corrosive properties. In the present work, ZnNi coatings were electrodeposited on steel substrates using a chloride bath containing ammonium salts. The effect of some experimental parameters, namely, potential and metal ion concentration ratio on the deposition kinetics of ZnNi system as well as on its physicochemical, morphological and anticorrosive properties has been investigated. For this purpose, an appropriate experimental work was performed by using both electrochemical (cyclic voltammetry, chronoamperometry, open circuit potential, potentiodynamic polarization) and nonelectrochemical (SEM-EDX) analysis methods. Based on the obtained results, it has been revealed that simultaneous codeposition of both elements Zn and Ni is possible in our experimental conditions. However, deposition kinetics exhibited a strong dependence on explored parameters. Also, morphological aspect and chemical composition of deposits are strongly influenced by metal ion concentration ratio. Investigation of corrosion behaviour confirms the protective effect of coatings acted as a sacrificial anode. Furthermore, increasing Ni content in the deposits induces a significant enhancement in corrosion resistance. Thus, Zn-Ni alloy coatings prepared from the Ni(II)-rich bath exhibited better corrosion resistance.

Determination of Electrochemically Active Surface Area in All-Solid-State Batteries

All-solid-state batteries (ASSBs) are currently receiving much attention as one of the most promising next-generation rechargeable battery systems due to their promise of high energy density and high safety. Despite many efforts to commercialize ASSBs, however, there are still many unresolved technical challenges. Unlike conventional lithium-ion batteries (LIBs), the interface between the cathode and electrolyte in ASSBs exhibits a complex degradation pattern that combines chemical and mechanical degradations. In particular, the high Ni content cathode materials in ASSBs are commonly known to suffer from significant additional degradation mechanism, e.g., volume expansion/contraction due to H2-H3 phase transitions at high voltages, resulting in particle cracking. This degradation of the integrity of the active material leads to a reduction in electrochemically active surface area (active area afterward) due to loss of contact between the active material and solid electrolyte, slow diffusion rate of lithium in the active material, and isolation of the active material. These issues are recognized as major contributors to cell performance degradation. Among these issues, the changes in the active area have a decisive impact on the rate of redox reactions that are key to battery charging and discharging kinetics, so accurate determination of the active area is crucial for the diagnosis and improvement of batteries. In the electrochemical analysis of ASSBs, the poor contact between the solid electrolyte and the active material, or the change of the contact properties during the battery operation, should be a very important consideration. Especially when determining kinetic factors such as charge transfer resistance and chemical diffusion coefficient of cathode material by electrochemical methods, the models we usually use include the electrode surface area value as an important variable, so the accurate estimation of the active area is indispensable for obtaining reliable electrochemical properties. Unlike typical LIBs, in ASSBs the active material/electrolyte interface contact properties change relatively significantly during repeated cycling, so devising a reliable technique to analyze the active area of active materials in ASSBs is very crucial for the research and development of ASSBs. However, to the best of our knowledge, there are still very few studies on this.In this study, we propose promising methods to measure the contact characteristics between the cathode material and the solid electrolyte in ASSBs, namely the electrochemically active surface area, and discuss their reliability based on intercomparison and literature reports. For this purpose, first, the method for determining the active area of active materials based on galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS) reported in conventional LIBs was reviewed. Then, its applicability to ASSBs was explored, and a way to improve the reliability of the analysis was proposed. Specifically, a three-electrode cathode half-cell experiment was conducted to analyze the active area of the Ni-rich cathode. The active area was calculated by comparing the diffusion coefficient measured by EIS with that obtained by GITT. When comparing the active area determined at different voltages, it was observed that the active area varies significantly with voltage most likely due to the volume change caused by the H2-H3 phase transition. The second electrochemical method performed for the determination of the active area of the active material is based on the quantification of the lithium intercalation sites on the cathode surface based on the analysis of the frequency factor in Arrhenius expression. For this purpose, battery at different charge states were kept at high temperatures for long periods of time to induce interfacial degradation. The temperature-dependent charge transfer resistance was then determined by EIS analysis, which was used to interpret the redox (or lithium absorption/desorption) reactions kinetically. The experimental results showed that the redox reaction rate followed exactly the Arrhenius relationship for all the charge states used, but the activation energies and frequency factors changed differently depending on the charge state. In this study, we discuss these results in relation to various phenomena that may occur during high-temperature aging, such as the formation of rock salt structures and cracks on the nickel-rich cathode surface, and try to estimate the change in active area. In this study, the electrochemical analysis methods of the contact characteristics between the cathode and the solid electrolyte in ASSBs will be examined in depth and their reliability will be assessed. In addition, further improvements in active area analysis techniques for active materials in ASSBs will be discussed.

Effect of the EMIM Cation on the CO2 Reduction Reaction on Gold

The electrochemical CO2 reduction reaction (CO2RR) is emerging as a promising method to produce carbon neutral chemical feedstocks. Additives or co-catalysts in the electrolyte can lower the activation barrier for CO2RR, yielding faster conversion rates at lower voltages. Recently, electrocatalytic CO2 reduction mediated by ionic liquids (IL) has been reported but with conflicting accounts to whether the ILs benefit CO2RR or adversely, the competing hydrogen evolution reaction (HER).We report the effect of added IL EMIM-Cl, specifically EMIM+, in aqueous solutions on the electrochemical CO2RR and competing HER on gold. We show the CO2 reduction current increases by ~1.5x with the highest amount of added EMIM+ relative to the pure electrolyte. Differential pulse voltammetry reveals an additional large change in the reduction current that only appears with both CO2 and EMIM+ present. Lastly, we use advanced electrochemical analysis methods to determine the reaction kinetics and preliminary evidence shows that the standard heterogeneous rate constant increases for the reaction at large overpotentials while the HER is suppressed at low overpotentials with EMIM+ present.Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

Corrosion and corrosion-friction effects induced by cutting fluid on binderless WC matrix composite and cemented carbide

The corrosion behavior of WC-4.3wt.%MgO-2wt.%ZrO2 composite in alkaline solution with 5% oil-based cutting fluid as medium was studied by electrochemical and microstructure analysis methods. The results showed that WM2Z composite has better corrosion resistance than YG3 and YG6 in alkaline environment. A stable passivation film was formed inside the WC phase after dissolution on the surface, which was the key reason for its high corrosion resistance. However, large areas of WC phase fell off in cemented carbide. In the process of corrosion-friction coupling experiment, due to the more excellent corrosion resistance and mechanical properties of WM2Z composites, the corrosion resistance and friction properties of WM2Z composites are better than that of YG3 cemented carbide. The corrosion-friction coupling effect on WM2Z was low, and the degree of damage to the topography after the experiment was relatively light.

Cathode Electrochemical Behavior of Aluminum Electrolysis in NaF-NaCl Based Molten Salt

Selective and efficient electrochemical analytical methods for the depositing process of metal aluminum are significant and necessary. The electrochemical measurement methods are based on the means of cyclic voltammetry, square wave voltammetry and constant potential electrolysis. The above methods are used to analyze the depositing process of metal aluminum in NaF-NaCl-Al2O3 and NaF-NaCl-NaAlO2 molten salt. Cyclic voltammetry analysis showed that Al3+ ions were reduced to metal aluminum through two consecutive steps. From the analysis of square wave voltammetry curve, the main reaction on the electrode was the reduction of metal sodium in the NaF-NaCl system, and the electron transfer number of the reaction was 0.80. With the addition of NaAlO2 and Al2O3 in the electrolyte, the electron transfer numbers of the two reduction steps were about 3.0. The process of reduction of Al3+ ions to aluminum was further proved by the analysis of the electrolysis curve at constant potential. The diffusion rate of Al3+ions and the rate of Al3+ reduction reaction increased with the addition of NaAlO2 and Al2O3 and the change of the potential.

Visual dual-mode aptasensor for non-small cell lung cancer exosome detection via HRP self-coupling enhanced oxidized iridium nanoparticle aggregation.

The main reason for the high mortality rate of non-small cell lung cancer is that patients are usually diagnosed at an advanced stage of the disease. Exosomes, small membrane vesicles secreted by normal cells or tumor cells, play a significant role in the progression of NSCLC. This study successfully optimized the preparation of artificial nanoenzymes self-coupling with horseradish peroxidase (IrO2NPs@HRP-AptCD63), without adding any ligand, demonstrating remarkable catalytic activity suitable for detecting the EGFR protein on the surface of NSCLC exosomes. When fused with the CD63 aptamer for identifying NSCLC exosomes, IrO2NPs@HRP showed enhanced catalytic activity in the 3,3',5,5'-tetramethylbenzidine-H2O2 oxidation-reduction system, thereby enhancing the colorimetric signal. This phenomenon can be distinguished by the naked eye and quantified using a UV-Vis spectrophotometer. Meanwhile, as the redox reaction occurs, the current signal of 3,3',5,5'-tetramethylbenzidine-H2O2, acting as an electrolyte, changes. The developed aptasensor generates dual-mode signal outputs, firstly, to visually assess the samples for their positive or negative status, and subsequently employ more in-depth electrochemical or colorimetric analysis methods for a detailed quantitative analysis of suspected positive samples. The detection limits of electrochemical analysis and colorimetric analysis were 0.9 × 103particles/mL and 0.14 × 103particles/mL, respectively. Compared with traditional biomarkers such as CA125, this method exhibits exceptional specificity, capable of simultaneously distinguishing serum exosomes of healthy volunteers, COPD patients, and NSCLC patients, promoting exosome detection in mouse models for tumor monitoring. Additionally, it elucidates the changes in EGFR protein expression on the surface of serum exosomes throughout the developmental trajectory.

Cations effect on the passive film for carbon steels in concrete simulated pore solutions

The composition of the passive film on the carbon steel surface is a key step for understanding the protective properties of the carbon steel in concrete environment. Since the different cation ions lead the different protective properties, the impacts of different cation ions (Ca2+ and Na+) exposed in simulated pore solutions on the passive film formation at the passivation stage are investigated by electrochemical measurements and surface analysis methods. To reveal the main reasons for the protective properties of the passive film and clarify the evolution for the formation of the passive film under different cation ions. Electrochemical measurements show that most part of the passive film has already formed in the initial 72 h in an NH solution, whereas 168h is needed to form most of the passive in a CH solution. In addition, 216 h is enough to form a completed passive film during the natural passivation period. Surface analysis methods elucidate the passive film formed in a CH solution has more protective properties than that in an NH solution because more iron oxides are produced. Furthermore, the presence of Ca2+ ions in the pore solution significantly improves the protective properties of the passive film.

Structural implications of ionic conduction in LaAlO3–Ce0.8Gd0.2O2-δ composite solid electrolyte

Investigations were done on the combinations of perovskites and fluorite structured composite electrolyte materials to check the possible enhancement of the ionic conductivity. For this purpose, the compounds, LaAlO3 (LAO) and Ce0.8Gd0.2O2-δ (CGO) were mixed in the weight ratios of 3:1, 2:2, and 1:3 to develop cost-effective composite electrolyte materials. Conductivity spectroscopy techniques were used to examine the dc electrical transport properties. Thermal properties were investigated using thermogravimetry analysis. Fourier transform spectroscopy was employed for bond structural study, while an X-ray diffractometer pattern analysis was employed to ensure the formation of composite structure. Scanning electron microscopy and energy dispersive X-ray spectroscopy studies confirm dense microstructure by a suitable weight proportion of component, homogeneous grain dispersion, and elemental confinement. The electrical behavior of composite electrolytes was demonstrated by electrochemical impedance spectroscopic analysis methods, which instigate the highest value of the conductivity of the order of 0.14x10−2 S cm−1 and lower activation energy value (0.72 eV) at temperature 700 °C for composite with LAO-CGO weight ratio of 1:3.

Rapid and reliable electrochemical detection of bisphenol S in thermal paper

Bisphenol S (BPS) is a common, persistent, and mobile chemical found in everyday products such as thermal paper. BPS can easily enter the body by migrating from the paper to the fingers, disrupting the endocrine system by mimicking the oestrogen hormone, thus negatively influencing human health. Assessing BPS levels in daily life is of great importance. This study introduces a rapid and reliable approach for detecting BPS in thermal paper and tap water by developing an electrochemical analytical method. This method allows for in-situ, real-time measurements. We present a simple, low-cost electrochemical sensor for detecting BPS using screen-printed electrodes based on carbon (SPEC) and single-wall carbon-nanotube (SPE-SWCNT) working electrodes. BPS was detected over a wide linear range from 1 to 400 μM. The detection limits were 0.73 μM and 0.87 μM for the SPE-C and SPE-SWCNT electrodes, respectively. Good repeatability was observed for both sensors when using one electrode 16 times, which demonstrates its potential for real-time environmental monitoring. Additionally, traditional chromatographic methods, high-performance liquid chromatography with a diode-array detector (HPLC-DAD), and liquid chromatography-mass spectrometry triple quadrupole (LCMS), were incorporated to enhance analytical capabilities. HPLC-DAD achieved a detection limit of 3 nM after solid-phase extraction preconcentration, while LCMS triple quadrupole demonstrated a detection limit of 10 pM without preconcentration. Electrochemical screen-printed electrodes can be employed for on-site analysis and health-risk assessments in everyday settings, such as shops. However, for detecting very low concentrations where time is not a constraint, LCMS quadrupole remains the preferred technique.

Synergistic effect of ZnO nanocomposite of Dodonea viscosa for corrosion inhibition in saline media

Abstract Dodonea viscosa-zinc oxide (DV-ZnO) nanocomposite was synthesized and characterized using Fourier transform infrared (FTIR), thermal gravimetric method (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). The most abundant compounds in the plant extract were explored using gas chromatography-mass spectrometry (GC-MS). FTIR indicated the existence of the different functional groups, XRD showed that the nanocomposite has the hexagonal wurtzite shape of ZnO nanoparticles, SEM-EDS showed a size of 50 nm, and elemental analysis depicts the existence of the different elements in the extract, which confirms, along with TGA results, the formation of DV-ZnO nanocomposite. The nanocomposite synergistic effect was examined for anticorrosion capabilities using gravimetric, electrochemical, and surface analysis methods. Both the plant extract and the nanocomposite exhibited corrosion inhibition abilities. However, the incorporation of the plant extract with ZnO increased the inhibition efficiency by 20 %. Weight loss and electrochemical methods concluded an inhibition efficiency of 80 % for DV-ZnO nanocomposite. The inhibition of the nanocomposite is due to the adsorption of the inhibitor on the carbon steel surface, which was verified using X-ray photoelectron spectroscopy and scanning electron microscopy (SEM). The adsorption was found to follow both Langmuir and Temkin isotherms. Surface examination using atomic force microscopy (AFM) found that the carbon steel surface roughness was decreased from the sample submerged in an uninhibited medium (Sa = 121.20 nm) when adding DV-ZnO nanocomposite (Sa = 22.95 nm) and DV plant extract inhibitor (Sa = 54.73 nm).

Electrochemical detection of benzenediols using carbon-supported catalysts

A novel implementation of an electrochemical sensors making use of Screen-Printed Electrodes (SPE) has been discussed. SPE's modified with Carbon-supported Platinum (Pt/C) and Gold (Au/C) were used to detect the three benzenediol isomers, Catechol (CC), Hydroquinone (HQ) and Resorcinol (RS) in acidic media using traditional electrochemical analytical methods such as Cyclic Voltammetry (CV), Chronoamperometry (CA) and Differential Pulse Voltammetry (DPV). Detection of each benzenediol in isolation was possible by CV measurements, and peak oxidation potentials for each isomer were noted. Simultaneous detection of more than one, or all analytes in the same solution was also observed through DPV, once again noting the peak oxidation potentials. Quantification limits were observed using CA's across concentration values ranging from close to saturation down to 1 mM for CC and HQ, and 100 nM for RS, until the recorded current values were nearly indistinguishable to a blank 1 M HCl solution containing no analyte(s), and also evaluating the maximum possible linear range of sensing. The analytes were introduced to the sensor elements in controlled amounts and the electrochemical responses of the sensor elements were recorded and processed. Measurements were repeated across two potentiostats to ensure reproducibility. With these results, successful detection of benzenediols in acidic environment was possible using modified SPE's, proving a potential viable mechanism for quick, simple and inexpensive Volatile Toxic Organic Compounds (VTOC) detection and monitoring.

Recent Advancement in the Fabrication of Colorimetric and Fluorometric Sensors for the Detection of Basic Amino Acids

Abstract:: Due to the biological importance of amino acids, the development of optical probes for these compounds has become a popular research topic in recent years. The amino acid fluorescence or colorimetric sensors are organized according to the reactions the amino acids go through and the related structural classification. Works on reaction-based chemosensors are categorized as either imine formation, Michael addition, thiazinane or thiazolidine formation, cleavage of a sulfonate ester, cleavage of a disulfide, metal complexes-displace coordination, or other mechanisms depending on the mechanisms between sensors and amino acids. Amino acids (AA), which comprise most proteins, are small molecules with a wide range of functional side-chain groups. Amino acids, therefore, have a variety of roles in physiological processes. Histidine (His), a member of this family, is required for tissue growth and repair as well as for weight gain. Lysine (Lys), another member of this family, is intimately linked to the Krebs-Henseleit cycle and polyamine synthesis, and an adequate amount of lysine in the diet is necessary for animals' metabolic processes and weight gain. Because it controls the transfer of metal elements in biological bases, tryptophan (Trp) is crucial to biological processes like protein synthesis, animal growth, and plant development. The majority of proteins are composed of amino acids (AA), which are tiny molecules with a variety of functional side chain groups. As a result, amino acids play a number of different roles in physiological processes. This family member's histidine (His) is necessary for weight gain, tissue growth, and repair. Another member of this family, lysine (Lys), is crucial for the Krebs-Henseleit cycle and polyamine production, and animals' metabolic activities and weight gain depend on appropriate lysine intake. Tryptophan (Trp) is an essential component of biological processes like protein synthesis, animal growth, and plant development because it regulates the transfer of metal elements in biological bases. Numerous attempts have been made to create new procedures for amino acid analysis as a result of the rising focus on human health, disease diagnosis, and therapy. Currently, spectroscopic, chromatographic, or electrochemical analytical methods are most frequently employed to identify and characterize amino acids. However, each method has certain disadvantages, such as the need for equipment and trained personnel, operational simplicity, analytical cost, test speed, and detection. Based on the important distinguishing characteristics of various amino acids to date, much research has been done on optical probes using indicator-displacement tests, metal complex coordination, particular interactions between probes and amino acids, and other techniques. We further subdivided the reaction-based probes into the following groups: production of imines, Michael addition, thiazinane or thiazolidine, cleavage of sulfonate ester, cleavage of disulfide, and others. Metal complexes-displace coordination. Due to some amino acids' similarity in structure and reactivity, it is still challenging to develop sensors that can selectively and sensitively identify amino acids from one another, such as the three biological thiols Cys, Hcy, and GSH. Specific reactions between probes and amino acids and other techniques have been extensively researched based on the significant characteristic features of diverse amino acids to date. We further divided the reaction-based probes into the following categories: metal complexes-displace coordination, imine creation, Michael addition, thiazinane or thiazolidine formation, cleavage of a sulfonate ester, cleavage of a disulfide; and others.

Aptamer-based electrochemical analysis platform for tumor cells and biomarkers detection

Early diagnosis and treatment of cancer can effectively improve patient survival rates and quality of life. One of the best options for early screening strategies is to track tumor cells and their markers. There is also an urgent need to develop accurate, susceptible, rapid, non-invasive, and low-cost detection methods. Among them, standard detection techniques for tumor cells include immunohistochemistry and histopathology, but they are expensive and require professional personnel. Both tumor cells and normal cells can secrete biomarkers, which can be obtained from biological samples (such as blood, urine, serum, etc.). Tumor biomarkers may be significantly elevated or changed in individuals with tumors. Common tumor biomarkers include proteins, nucleic acids, etc. In recent years, aptamer-based electrochemical analysis methods have been widely used in cancer diagnosis. Aptamers are obtained through in vitro screening technology and have high selectivity and affinity, which can improve the sensitivity of electrochemical analysis technology. This article reviews the achievements of aptamer-based electrochemical analysis methods in detecting tumor cells and tumor markers and the challenges and development prospects in cancer diagnosis.

Construction of SnO2 buffer layer and analysis of its interface modification for Li and Li1.5Al0.5Ge1.5(PO4)3 in solid-state batteries

SnO2 layer between Li1.5Al0.5Ge1.5(PO4)3 (LAGP) and lithium anode was prepared through simple scratch-coating process to improve interface properties. The physical phase, morphology, and electrochemical properties of Li/SnO2/LAGP structure were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and electrochemical analytical methods. It was found that SnO2 layer effectively improved the interface stability of LAGP and lithium anode. The prepared Li/SnO2/LAGP/SnO2/Li symmetric cell exhibited a large critical current density of 1.8 mA cm−2 and demonstrated excellent cycling characteristics. The polarization voltages of symmetric cell were 0.1 V and 0.8 V after 1000 h of cycling at current densities of 0.04 mA cm−2 and 0.5 mA cm−2, respectively. Li/SnO2@LAGP/LiFePO4 solid-state full cells were also assembled, exhibiting a discharge specific capacity of 150 mAh g−1 after 200 cycles at 0.1C with capacity retention rate of 96 %. The good interface properties of Li/SnO2/LAGP structure are attributed to the transformation of SnO2 layer into a buffer layer containing Li2O, Sn0, and LixSny alloy during cycling process, which effectively inhibits the reduction reaction between LAGP and lithium anode.

Preface

The 4th Edition of the International Altamira Materials and Devices Encounter (EMDA 4) was successfully held in hybrid format, on November 16th and 17th, 2023 with 196 participants on-site at CICATA Altamira, and ca. 180 participants online. The Scientific Program included 13 invited conferences from around the globe, with researchers from Malaysia, India, Azerbaijan, Romania, United Kingdom, Morocco, USA, Honduras, Mexico, Colombia giving their talks in four sessions (Semiconductors, Modelling, Materials and Engineering and Physical Sciences).Six Workshops were imparted: Elemental Analysis by X-ray Fluorescence, Production of Biobatteries from Plants, Creation of Metamaterials by 3D Printing, Introduction to AI for Materials Science, Electrochemical Methods of Analysis, ANSYS Mechanic Introductory Training. Graduate and undergraduate students benefited from these Workshops, which were also transmitted by YouTube live as well as the rest of the activities of the Conference.https://youtube.com/playlist?list=PL9d20U28c14xN3a1uvGW8-Tbrulu8-HOD&si=-X2PIPFe5gMoh32XA hybrid poster session with 46 posters showing the groundbreaking results of researchers and students was done. The submissions provided the public with a broad view of physics, semiconductors, materials, batteries, engineering applications, mathematical and computational science methods, novel concepts, ideas, and tools. The best posters were judged by a multidisciplinary jury, in two categories: Materials and Devices. The list of winners is depicted in this book.There were 43 conference paper submissions, and after a strict, double-blinded peer review process, 23 papers were selected by the Editor to be published in this volume. A total of 11 reviewers participated in this conference, who provided their professional and objective feedback to the authors to ensure the quality of the manuscripts according to the IOP Editorial’s Guidelines. The accepted papers are grouped into three general topics, i.e. Engineering Applications, Batteries/Supercapacitors and Semiconductors.The papers entitled “nS1-xSex alloy deposition by RF magnetron co-sputtering for potential photoelectrochemical applications”, “Wide-angle microwave attenuation response of a multilevel metastructure based on rGO/Fe3O4/PPy: an in-silicon study”, “Wastewater treatment from graphene oxide synthesis process”, “Physicochemical characterization of urban dust in Southern Tamaulipas using X-ray fluorescence”, “Delignification and characterization of Tule (Typha Dominguensis) for its potential use in the production of green concrete”, won the best materials poster and the paper entitled “Open Source electronic system with OLED screen monitoring of Plant Based Batteries”, “One-bit register based on 180nm CMOS technology”, “Optoelectronic system for measuring sugar content in citrus fruit” won the best devices poster after being reviewed by the session’s jury at the conference.A special acknowledgement is given to Instituto Politecnico Nacional through its Secretaria de Investigacion y Posgrado, from which financial support was possible to waive the fees for this event including the fees for paper publication, which was of capital importance because the highest participation was from graduate and undergraduate students.The kind sponsorship of SCM, SATELSA, and Soporte Analitico Especializado for the Conference banners and specific logistic needs, is kindly granted.Acknowledgements are also given to the Conference Staff, composed of CICATA Altamira and UV students who were the success factor of the Conference.The Organizers also grant the support from CICATA Altamira for the use of their facilities and the all the event logistics, as well as to the effort of the Scientific Program and Technical Committees, who did a great job preparing the event, contacting the Lecturers, confectioning the Program, reviewing the posters and the papers and making valuable suggestions for the authors to improve their work. We also would like to express our gratitude to the external reviewers, who kept the quality of the submitted papers and qualified the presented posters.Finally, on behalf of the Organizing Committees, we would like to express our sincere gratitude to all participants and speakers who contribute to make this event a great success.Looking forward to seeing you in 2025!Organizing Committee of EMDA 4th 2023List of Organizing Comittee, Conference Chair, Program Chair, Program Co-chairs, Steering Committee, Support Committee/Conference Staff and Organizations are available in this pdf.

Temperature and Reaction Time’s Effects on N80 Steel Corrosion Behavior in Supercritical CO2 and Formation Water Environments

In the present study, an immersion experiment was carried out to examine how N80 steel corrodes when exposed to formation water containing dissolved CO2 and supercritical CO2 (Sc-CO2) along with water vapor. We employed electrochemical and surface analysis methods to examine the influence of various factors, including the temperature and duration of immersion, on the extent of corrosion. The results show that the corrosion patterns of N80 steel in a supercritical CO2 environment and CO2-saturated formation water differed significantly. The presence of similar corrosion features was suggested by the constant structure of the corrosion products identified in the formation water. However, the morphology of the corrosion product was complex in the supercritical CO2 environment, exhibiting features of pitting and localized corrosion. Furthermore, a non-linear trend in the corrosion rate was observed between 40 °C and 120 °C. Specifically, the rate of corrosion declined from 40 °C to 80 °C, but it then resumed its growth from 80 °C to 120 °C. These findings suggest that very high temperatures could lead to the destruction of corrosion products and subsequently enhance the corrosion process.

Nanocomposite modified electrode based on polyaniline/Ti3C2 for the simultaneous detection of purine bases and uric acid

In this study, a nanocomposite of Polyaniline/titanium carbide (PANI/Ti3C2) was synthesized through self-assembly and in situ polymerization for use as a sensor material to simultaneously detect guanine (G), adenine (A), and uric acid (UA). X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were utilized to confirm the successful synthesis of PANI/Ti3C2. Electrochemical analysis methods including differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) were used to detect the electrochemical performance of PANI/Ti3C2 modified glassy carbon electrode (PANI/Ti3C2/GCE). The pH dependence, electrochemically active surface area (ECSA), electron transport, stability, reproducibility, sensitivity, and selectivity of the modified GCE were examined. Compared to previous reports, the nanocomposite exhibited excellent performance. Uric acid, guanine, and adenine detection limits were 0.33, 0.31, and 0.28 μM, respectively, over concentration ranges of 0.62 - 20.10, 0.31 - 17.00, and 0.31 - 17.00 μM. The nanocomposite demonstrated high recovery and low error in serum sample detection. In summary, PANI/Ti3C2 is a sensor material with excellent electrochemical properties.

Development of a novel electrochemical method for the quantitative analysis of vandetanib in the presence of anionic surfactant utilizing a bare carbon paste electrode

Development of a novel electrochemical method for the quantitative analysis of vandetanib in the presence of anionic surfactant utilizing a bare carbon paste electrode

Electroanalysis in Pharmacogenomic Studies: Mechanisms of Drug Interaction with DNA.

The review discusses electrochemical methods for analysis of drug interactions with DNA. The electroanalysis method is based on the registration of interaction-induced changes in the electrochemical oxidation potential of heterocyclic nitrogenous bases in the DNA molecule and in the maximum oxidation current amplitude. The mechanisms of DNA-drug interactions can be identified based on the shift in the electrooxidation potential of heterocyclic nitrogenous bases toward more negative (cathodic) or positive (anodic) values. Drug intercalation into DNA shifts the electrochemical oxidation potential to positive values, indicating thermodynamically unfavorable process that hinders oxidation of nitrogenous bases in DNA. The potential shift toward the negative values indicates electrostatic interactions, e.g., drug binding in the DNA minor groove, since this process does not interfere with the electrochemical oxidation of bases. The concentration-dependent decrease in the intensity of electrochemical oxidation of DNA bases allows to quantify the type of interaction and calculate the binding constants.

Voltammetry in the pharmaceutical analysis: A review

Due to its sensitivity, selectivity, simplicity and costeffectiveness, the role of electrochemical analysis methods increases from year to year. This also applies to the use of various voltammetry options in the analysis of medicines. This mini-review is devoted to the analytical capabilities of cyclic voltammetry used in manufacturing technologies and clinical diagnostics of antihypertensive drugs. The main goal pursued by the authors of this article is to attract the attention of specialists to the problem of analytical control of medicines, and, first of all, antihypertensive drugs, using methods of voltammetric analysis. According to the authors, this will allow a deeper understanding of the cause of hypertension and the subsequent eradication of this disease, which will certainly affect the duration of a healthy human life.