Electrochemical Methods Research Articles

Emerging Technologies for Decarbonizing Silicon Production

AbstractSilicon (Si) is an important material for alloying, solar photovoltaics, and electronics. However, current methods of producing silicon require energy consumption of around 11–13 kWh/kgSi and direct carbon emissions are 4.7–5 tons CO2 per ton Si which conflicts with global efforts to limit climate change. In this work, we discuss several promising methods for reducing or eliminating carbon emissions from the silicon production process. Such methods include using biocarbon, integrating the current process with carbon capture and utilization/storage (CCU/CCS), metallothermic reduction, hydrogen reduction, and molten salt electrolysis. We present the positive aspects and challenges of each approach. Biocarbon coupled with CCU/CCS is the most industrially mature technology and can be carbon–neutral or -negative but is not carbon-free. Hydrogen directly reducing silicon dioxide is not thermodynamically favorable, but it may be viable to use hydrogen in conjunction with other processes to reduce emissions. Metallothermic and electrochemical methods of production are promising and have the potential to create high-purity silicon with no reduction-related carbon emissions but have only been demonstrated at lab scale. Economic viability will likely be the next determining factor for which technologies are more widely researched and implemented. Graphical Abstract

Insight into the corrosion inhibition performance of dimethyldiallylammonium chloride acrylamide copolymer for mild steel in acidic solution

Dimethyldiallylammonium chloride acrylamide (DADMAC-AAM) copolymer was firstly applied as a novel corrosion inhibitor for carbon steel in acidic solution. Electrochemical, theoretical and computational methods were performed to illustrate the corrosion inhibition mechanism of DADMAC-AAM. Results of electrochemical tests indicated that DADMAC-AAM effectively slowed down corrosion rate of mild steel in HCl solution as a mixed-type corrosion inhibitor. Its corrosion inhibition efficiency increased with dosage, and the maximum value reached about 92.44 % with adding 100 mg/L. In-situ scanning vibration electrode technique illustrated that the corrosion inhibition performance of DADMAC-AAM increased with immersion time. Metal surface was covered with a dense hydrophobic film due to the physical-chemical adsorption of DADMAC-AAM molecules, and the adsorption behavior obeyed to the Langmuir adsorption isothermal model. Theoretical calculations were carried out to explain the corrosion inhibition mechanism, and the increase of active energy indicated that the strong inhibitive action of DADMAC-AAM molecule could be due to the increase of activation energy barrier of corrosion reaction. Results obtained from computational simulations proved that DMDMAC-AAM molecules adsorbed on metal surface through interactions between N or O and Fe atoms. This adsorption film could retard the invasion of corrosive species, thus protecting metal from corrosion.

Highly Efficient Degradation of 2-Methylisoborneol by Laccase Assisted by a Micro-Electric Field

Taste and odor (T&O) compounds have emerged as crucial parameters for assessing water quality. Therefore, identifying effective methodologies for the removal of these compounds is imperative. In this study, an effective approach utilizing laccase assisted by a micro-electric field was developed for the degradation of 2-methylisoborneol (2-MIB). For this purpose, the optimal conditions for the laccase-catalyzed degradation of 2-MIB were determined, and they were pH 4.0, 25 °C, 150 rpm, 0.1 U/mL of laccase, and 200 ng/L of 2-MIB. Under these specified conditions, the degradation efficiency of 2-MIB was approximately 78% after a 4 h reaction period. Subsequently, the introduction of an electric field yielded a synergistic effect with the enzyme for 2-MIB degradation. At an electric current intensity of 0.04 A over a 4 h duration, the degradation efficiency increased to 90.78%. An analysis using SPME-GC/MS provided information on the degradation intermediates of 2-MIB resulting from laccase-catalyzed degradation, electrocatalytic degradation, and micro-electric-assisted laccase degradation. The potential degradation pathways of 2-MIB illustrated that these three methods result in common degradation products, such as capric aldehyde, nonylaldehyde, and 2-ethylhexanol, and their final products include 3-pentanone, acetone, and 2-butanone. This study provides an enzyme–electrochemical method for the efficient and rapid degradation and removal of 2-MIB. The strategy of laccase catalysis assisted by a micro-electric field has good potential for the removal of pollutants from the natural environment.

Preparation and Characterization of EVAc/ TiO2 Nanocomposites Coating for Oil Pipes Protection

The spin coating process was used in this study to create nanocomposites of ethynevinyl acetate copolymer reinforced with nano titania nanoparticles at various ratios (50, 100, & 150 part/million). Using Fourier-transform infrared spectroscopy (FTIR), different types of reactions between TiO2 and EVAc were investigated. Deferential Scanning Calorimetry was used to study melting point of thin films. As well as , anti corrosion resistance of thin films using electrochemical method were studied Results show that the adding of TiO2 nanoparticles enhanced the thermal characteristics of nano composite thin films, Tm increasing from 66 oC to 71 oC, The results of the FTIR analysis demonstrate that the nanoscale TiO2 and EVAc are physically reacting. Anti-corrosion behavior shows that the corrosion current reduces from 188 mA to 1 nA and corrosion resistance was increased. Additionally, the efficacy of inhibition increased from 0.0 to 99%. with adding Nano TiO2 with 150 ppm to thin films.

Dual motion principal Au-Ni-PDA-CuS micromotors with NIR light and magnetic effect for detection of organic dye

Copper sulfide (CuS), despite some disadvantages such as rapid recombination, easy aggregation, photodegradation of oxidized CuS, and a limited ability to absorb light energy, is still a good photocatalyst. This semiconductor material with a narrow bandgap plays a significant role in the degradation of organic dyes. However, due to these mentioned drawbacks, it requires a linker. The polymer used as this intermediate binder is polydopamine (PDA). PDA not only eliminates the disadvantages of CuS but also facilitates its attachment to the carrier system, which is a micromotor. However, the purpose of using PDA here is not only to eliminate the disadvantages of CuS but also to enable light-triggered motion due to its sensitivity to near-infrared (NIR) radiation. Similarly, CuS, which is a good catalyst, has been used in the polymerization reaction to catalyze dopamine’s conversion to PDA. The micromotor used in the study, based on the dual-motion principle, exhibits high stability and good reusability. The synthesized Au-Ni-PDA-CuS composite micromotor demonstrates a good photocatalytic degradation performance under NIR irradiation. The degradation efficiency is 54.48% at the lowest concentration, while it is 17.72% at the highest concentration, indicating the effectiveness of the synthesized micromotors in achieving good photocatalytic degradation at low concentrations. As a result of the photocatalytic degradation reaction, cyclic voltammetry was performed for 100 cycles to demonstrate the stability of the micromotors.This study is based on the electrochemical method for the photocatalytic degradation of methyl red (MR), an azo dye, using micromotors with a dual-motion principle. Following the development on an azo dye, this study applied the same procedure on real samples, and through in vitro investigation, the photocatalytic degradation of the composite motor on real samples was observed electrochemically.

Untargeted authentication of fruit juices based on electrochemical fingerprints combined with chemometrics. Adulteration of orange juice as case of study

This work presents a novel strategy for authentication of fruit juices. The methodology is based on an electrochemical method combined with chemometrics. In addition, the case of orange juice adulteration with grapefruit juices was studied using this methodology. The electrochemical fingerprint of different juices showed the influence from different polyphenols according to the type of fruit. First, Principal Component Analysis (PCA) was able to differentiate clusters of different juices, being the higher group distance within apple, orange, and grape juices samples. On the other hand, partial least-squares – discriminant analysis (PLS-DA) and PCA-linear discriminant analysis (LDA) were used as classification methods, obtaining better results for orange and apple models. Furthermore, good results were obtained for the authentication of orange juices, compared to other juices, with an error rate of 0.04 for cross-validation. In the case of adulteration of orange juice was detected using PLS-DA at an adulteration level as low as 1%. Regression vectors for all models highlighted identifiable potential values that could be related to the main polyphenols in each type of fruit. This electrochemical method is rapid, low-cost, and compatible with on-site analysis compared to other laborious analysis described in the literature.

Bimetallic Fe/Co-MOF dispersed in a PVA/chitosan multi-matrix hydrogel as a flexible sensor for the detection of lactic acid in sweat samples.

Anovel bimetallic Fe/Co-metal-organic framework (MOF) hydrogel-based wearable sweat sensorwas developed. Morphological and structural analysis of the hydrogel shows uniformly sized spines and spindle-shaped particles of the Fe/Co-MOF, and it has a high surface area (132.306 m2g-1) and porosity (0.059 cm3g-1) as confirmed by Brunauer-Emmett-Teller (BET) studies. The integration of the bimetallic MOF into a polyvinyl alcohol/chitosan (PVA/CS)-mixed matrix resulted in a multiple network hydrogel. The optimisation study investigated the effects of different pH of the PBS electrolyte, scan rates, and accumulation time in voltammetry. The electrochemical methods such as cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS) provided information on the redox behaviour, electrochemical stability, and catalytic activity of the hydrogel. The sensor demonstrates a wide linear detection range from 0.05µM to 100mM, a superior sensitivity of 0.02mAmM-1cm-2, and a lower limit of detection of 0.01µM . Active sites distributed over the hydrogel surface, specifically Fe2+ and Co2+ within the MOF structure, catalyse the oxidation of L-lactic acid, resulting in electron transfer and the formation of pyruvic acid. Notably, the fabricated sensor exhibits high selectivity, effectively discriminating against interfering species such as uric acid, ascorbic acid, glucose, urea, dopamine, NaCl, and CaCl2. Real-time analysis conducted in a simulated sweat sample via the standard addition method resulted in good recovery percentages of a minimum of 98%. The work presented here is a versatile and simple platform for point-of-care testing, especially for athletes and military personnel.

Lab-on-a-chip paper-based electrochemically assisted solid-phase microextraction and ion selective sensor for determination of naproxen in biological fluid samples

BackgroundThe integration of paper-based analytical devices with lab-on-a-chip technology has opened up new possibilities for miniaturized, rapid, low cost and portable diagnostic testing in resource limited settings. This work introduces an integrated lab-on-a-chip platform coupling paper-based analytical devices (LOC-PADs) for dual usage: electrochemically controlled solid-phase microextraction (EC-SPME) and determination of naproxen (NAP) by potentiometric ion-selective electrode (ISE) in biological samples. ResultsConductive papers were successfully fabricated by a chemical procedure. Thereupon, a conducting molecularly imprinted polymer (CMIP) film based on PPy and an anionic model drug (NAP) as a template were applied to the conductive paper substrate via electrochemical methods. A microfluidic chip device was employed to assess the analytical performance of the fabricated paper-based CMIP. The designed chip is divided into two parts with a microfluidic channel between them. The first chamber is an extraction zone for EC-SPME of NAP by using the CMIP paper as a selective sorbent. The second chamber is the detection zone and consists of a paper-based NAP ion selective sensor for potentiometric detection of drug. The analytical process was investigated and optimized for each chamber. Remarkable selectivity towards NAP was achieved in the concentration range from 4.0 × 10−7 to 1.0 × 10−2 mol L−1 with determination coefficient (R2 = 0.99) and the limit of detection (LOD) was 2.0 × 10−7 mol L−1. Anionic Nernstian compliance was gained −58.5 ± 0.5 mV decade−1, and response time in the detection step was 7s for ISE. Satisfactory spiking recovery values within the acceptable range of 90–110 % with RSDs ≤7 % were achieved for the analysis of real samples with fully portable LOC device. SignificanceThe LOC-PADs were favorably used for selective extraction and determination of NAP in serum and saliva samples, respectively. EC-SPME caused sample clean-up, reduced or eliminated different interferences and enhanced selective response of ISE as detection zone of device. Integration of EC-SPME and ISE in a single chip enabled easy and fast determination of trace amounts of NAP in limited real sample volumes, and fully portable advantages.

Synthesis and Mechanism of a Green Scale and Corrosion Inhibitor.

A new green water treatment agent, a poly(aspartic acid)-modified polymer (PASP/5-AVA), was synthesized using polysuccinimide and 5-aminovaleric acid (5-AVA) in a hybrid system. The structure was characterized, and the scale and corrosion inhibition performance were carried out with standard static scale inhibition and electrochemical methods, respectively. The mechanism was explored using XRD, XPS, SEM, and quantum chemistry calculations. The results indicated that PASP/5-AVA exhibited better scale and corrosion inhibition performance than PASP and maintained efficacy and thermal stability of the scale inhibition effect for a long time. Mechanistic studies indicated that PASP/5-AVA interferes with the normal generation of CaCO3 and CaSO4 scales through lattice distortion and dispersion, respectively; the combined effect of an alkaline environment and terminal electron-withdrawing -COOH groups can induce the stable C- ionic state formation in -CH2- of the extended side chain, thus enhancing its chelating ability for Ca2+ ions. At the same time, the extension of the side chain length also enhances the adsorption ability of the agent on the metal surface, forming a thick film and delaying the corrosion of the metal surface. This study provides the necessary theoretical reference for the design of green scale and corrosion agents.

Redox kinetics of multi-electron transfer reactions of polyoxometalates (POMs) relevant to electrochemical devices

The formal equilibrium potential (E0′) and heterogeneous rate constant (k0) are characteristics of any electron-transfer reaction. The estimation of these characteristics for very fast multiple electron-transfer reactions of polyoxometalates (POMs) relevant to various applications including redox flow batteries, hydrogen storage materials, and electrocatalysis is highly challenging by the conventional electrochemical methods. Therefore, E0′and k0 (k0∼10–2 cm sec‑1) of such reactions (for e.g., that of tungstosilicic acid (SiW12) and phosphotungstic acid (PW12)) separated by small potential windows are estimated from the background current free higher harmonic response of large-amplitude AC voltammetry. For SiW12/PW12 redox species, the E0′ values of processes 1, 2, and 3 estimated from the minima of second harmonic response are -0.326/-0.127, -0.530/-0.380 and -0.691/-0.701 (V vs. Ag/AgCl), respectively. The k0 values of the first redox process (P1) of SiW12 (SiW12/ SiW12-,4.8 × 10–2 cm sec‑1) and PW12 (PW12/PW12-,5.2 × 10–2 cm sec‑1) estimated from the large-amplitude AC voltammetry are further validated through the impedance measurement (2.1 × 10–2 and 2.4 × 10–2 cm sec‑1). The uniqueness of large-amplitude AC voltammetry over conventional DC techniques and impedance spectroscopy is illustrated. The relevance of k0 values in the context of electrocatalytic processes and RFBs system is also presented.

Corrosion behavior and mechanism of Cr10Mo1 steel subjected to different corrosive ions in simulated concrete pore solution

The corrosion of pre-passivated Cr10Mo1 steels in simulated concrete pore solution of saturated Ca(OH)2 induced by different corrosive ions were investigated, namely Cl−, SO2- 4, and combination of Cl− and SO2- 4. Electrochemical methods, Pourbaix analysis of Fe–Cr–H2O system and DFT calculation were adopted to characterize corrosion behavior and reveal underlying mechanism. Results showed that while sulfate may induce corrosion at higher threshold value, the scenario of chloride alone leads to lowest corrosion potential, linear polarization resistance and highest corrosion rate, and the presence of SO2- 4 ions mitigate corrosion risk under the coexistence condition of chloride and sulfate. A two-step reaction model of competitive adsorption-catalytic corrosion was proposed based on theoretical analysis and DFT calculation results.

Silver(I) complexes with antifungal drug econazole: Structural characterization and antimicrobial activity study

Two new silver(I) complexes with the antifungal agent econazole (ecz) of the general formula [Ag(еcz)2]X, X = CF3SO3− (Ag1) and PF6− (Ag2), were synthesized and structurally characterized by spectroscopic (1H NMR, IR and UV–Vis) and electrochemical methods. The crystal structure of Ag2 was determined by single crystal X-ray diffraction analysis, confirming an ideal linear geometry of the silver(I) ion in this complex. In addition, by utilising Hirshfeld surface analysis (HSA), it was verified that the crystal structure of Ag2 is stabilized by H⋯H, H⋯Cl, C⋯H, and H⋯F interactions. Density functional theory (DFT) calculations provided additional evidence for formation of the complexes in the solid state and their stability in solution. The coordination of ecz to the silver(I) ion endowed this agent with antibacterial activity against Gram-positive (Pseudomonas aeruginosa and Escherichia coli) and Gram-negative (Staphylococcus aureus and Listeria monocytogenes) bacteria. The most significant antibacterial activity of Ag1 and Ag2 was observed against S. aureus with 56- and 73-fold improvement, respectively, compared to the parent drug. Moreover, a study of the bacterial antibiofilm activity revealed that these complexes were able to prevent approximately 90 % of biofilm formation at their low concentrations. Also, both complexes have shown more pronounced anti-Candida activity than econazole itself, being less toxic on the human normal fibroblast cell line MRC-5. The total amount of ergosterol was reduced in the presence of the subinhibitory concentrations of Ag1 and Ag2 complexes, which was also confirmed by a molecular docking study with two isomers of cytochrome P450 sterol 14α-demethylase, CYP51B and CYP130, as target receptors.

NiCoFeS/rGO nanozyme-mediated multifunctional homogeneous sensing system for ultrasensitive electrochemical assay of pesticides residues in fruits and vegetables

In this work, a homogeneous sensing platform was constructed for ultrasensitive electrochemical organophosphate pesticides (OPs) detection based on nano-enzyme NiCoFeS/rGO with high peroxidase-like activity. In the presence of H2O2, NiCoFeS/rGO catalyst oxidized o-phenylenediamine (OPD) to produce yellow OPDox with strong absorbance and reduction peak current. This activity could be inhibited by thiocholine (TCh) produced by acetylcholinesterase (AChE). However, presence of organophosphates (OPs) could inhibit AChE and reduce TCh production, enabling protect the peroxidase-like activity of NiCoFeS/rGO. So, according to the increased signal of OPDox, the content of OPs could be measured by colorimetric or electrochemical mode. Using electrochemical analysis mode and optimizing experimental conditions, the detection limit was low (9.74fg mL−1) and the linear range was wide (12.5fg mL−1-1.25 ng mL−1). The selectivity, stability reproducibility and practicability of the method were investigated. At the same time, the analysis results of colorimetric and electrochemical method for AChE and colorimetric method for OPs were preliminarily determined, respectively.

Iron and Nickel Substituted Perovskite Cobaltites for Sustainable Oxygen Evolving Anodes in Alkaline Environment.

Perovskite oxides have great flexibility in their elemental composition, which is accompanied by large adjustability in their electronic properties. Herein, we synthesized twelve perovskites oxide-based catalysts for the oxygen evolution reaction (OER) in alkaline media. The catalysts are based on the parent oxide perovskite Ba0.5Gd0.8La0.7Co2O6-δ (BGLC587) and are synthesized through the sol-gel citrate synthesis route. To reduce the demand on cobalt (Co), but also increase the intrinsic catalytic activity of BGLC587 for the OER, we substitute Co on the B-site with certain amounts of Fe and Ni, synthesizing catalysts of the general formula Ba0.5Gd0.8La0.7Co2-x-yFexNiyO6-δ. A plethora of physicochemical and electrochemical methods suggest that an Fe content between 30% and 70% increases the intrinsic catalytic activity of BGLC587, while Tafel slopes in combination with in-situ Raman spectroscopy suggest the rate determining step is likely a proton-exchange reaction, progressing possibly through the lattice oxygen mechanism (LOM). We apply one of the optimized, Co-substituted perovskites in a monolithic, photovoltaic (PV)-driven electrolysis cell and we achieve an initial solar-to-hydrogen (STH) conversion efficiency of 10.5% under one sun solar simulated illumination.

Trifolium repens extracts as a green corrosion inhibitor for carbon steel in a 3.5% NaCl solution

BackgroundMaterial degradation is a major issue that has been the subject of intense research and investigation by the scientific community. It has harmful consequences that require serious and careful intervention. However, restrictions on the use of inhibitors containing toxic compounds pose a significant challenge to the implementation of effective corrosion treatments. This has necessitated a continuous search for new and innovative ways to protect against material damage. Plant-derived natural inhibitors offer several advantages, including potent inhibitory effects, lack of toxicity, biodegradability, and environmentally sustainable origins. The purpose of this research was to evaluate the corrosion resistance of API5LX60 carbon steel in a 3.5 % NaCl environment using Trifolium repens as an environmentally friendly inhibitor. MethodsThe inhibitor extract was analysed using Fourier Transform Infrared (FTIR) spectroscopy. However, gravimetry and electrochemical methods (potentiodynamic polarization and electrochemical impedance spectroscopy (EIS)) were used to investigate the corrosion behaviour. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to examine the surface morphology. Significant findingsAfter testing a range of concentrations in a 3.5 % NaCl medium, the highest level of inhibition (98 %) was obtained at 20 ppm, confirming the mixed action of the inhibitor with predominantly cathodic action. The inhibition mechanism involved physical adsorption on metal surfaces according to the Langmuir model, which enhances the corrosion-inhibiting ability; the extract forms a protective layer that successfully inhibits corrosion, as confirmed through electrochemical and surface analysis. These results demonstrate that the extract acts as a potent anticorrosive agent.

Corrosion Resistance and In Vitro Biological Properties of TiO2 on MAO-Coated AZ31 Magnesium Alloy via ALD

The surface corrosion of magnesium alloys is effectively addressed currently by the creation of a micro-arc oxidation (MAO) ceramic layer. However, oxide film porousness restricts magnesium alloy use. Thus, this work used atomic layer deposition (ALD) to create a TiO2 coating on MAO-coated AZ31B magnesium alloy to plug micropores and increase corrosion resistance and biological characteristics. The samples were analyzed using SEM, EDS, XPS, and XRD to determine their surface appearance, chemical content, and microstructure. Micro-arc oxidation produced a 20 μm oxide coating. The TiO2 film reached 47.41 nm after 400 atomic layer deposition cycles. All corroded samples were tested for corrosion resistance using electrochemical and hydrogen evolution methods and examined for surface morphology. In vitro cell experiments examined biocompatibility. The results indicate that the TiO2 layer sealed the MAO coating’s micro-pores and micro-cracks, enhanced corrosion resistance, and preserved surface morphology following corrosion. The TiO2/MAO composite coating is more biocompatible than the substrate and MAO coating. This research proposes coating AZ31B magnesium alloy for bio-remediation to increase corrosion resistance and biocompatibility.

A semiconductor SERS sensor of corrosion-resistant PPy/GO composite film by electrochemical growth for detecting crystal violet residues in fresh fish tissue

Crystal violet (CV) residues in Marine food have produced a severe health threat in human life. In this study, we proposed a semiconductor surface-enhanced Raman scattering (SERS) sensor of corrosion-resistant Polyaniline/Graphene oxide (PPy/GO) film by electrochemical growth method to detect CV residues in fresh fish tissue. A PPy/GO dispersion solution was one-step deposited on a stainless steel sheet surface by electrochemical polymerization process to form a PPy/GO composite film acting as a semiconductor SERS substrate. Since the substrate of PPy/GO film was mainly composed of GO sheet without other metals, it had a good corrosion resistance. The SERS enhancement factor and charge transfer intensity PCT of PPy/Go SERS substrate for CV molecules were up to 1.18 × 106 and 0.903, respectively. Furthermore, the limit of detection (LOD) of PPy/GO SERS substrate could reach 1.58 nM. In addition, SERS sensor of PPy/GO film could identify CV residues in fresh fish tissues, and its recovery rate was 91.8 %–107 %. This preparing method and detecting method we proposed PPy/GO SERS substrate provide a new pathway for detecting CV residues in Marine food.

Analytical Methods for Assessing Thiol Antioxidants in Biological Fluids: A Review.

Redox metabolism is an integral part of the glutathione system, encompassing reduced and oxidized glutathione, hydrogen peroxide, and associated enzymes. This core process orchestrates a network of thiol antioxidants like thioredoxins and peroxiredoxins, alongside critical thiol-containing proteins such as mercaptoalbumin. Modifications to thiol-containing proteins, including oxidation and glutathionylation, regulate cellular signaling influencing gene activities in inflammation and carcinogenesis. Analyzing thiol antioxidants, especially glutathione, in biological fluids offers insights into pathological conditions. This review discusses the analytical methods for biothiol determination, mainly in blood plasma. The study includes all key methodological aspects of spectroscopy, chromatography, electrochemistry, and mass spectrometry, highlighting their principles, benefits, limitations, and recent advancements that were not included in previously published reviews. Sample preparation and factors affecting thiol antioxidant measurements are discussed. The review reveals that the choice of analytical procedures should be based on the specific requirements of the research. Spectrophotometric methods are simple and cost-effective but may need more specificity. Chromatographic techniques have excellent separation capabilities but require longer analysis times. Electrochemical methods enable real-time monitoring but have disadvantages such as interference. Mass spectrometry-based approaches have high sensitivity and selectivity but require sophisticated instrumentation. Combining multiple techniques can provide comprehensive information on thiol antioxidant levels in biological fluids, enabling clearer insights into their roles in health and disease. This review covers the time span from 2010 to mid-2024, and the data were obtained from the SciFinder® (ACS), Google Scholar (Google), PubMed®, and ScienceDirect (Scopus) databases through a combination search approach using keywords.

Electrochemical production of HO2- and O2 for sulfide removal from sewage

In this study, a comparative analysis of two electrochemical methods for sulfide control in sewer networks was performed for the first time. In addition, the mechanism of sulfide control by HO2- was elucidated, and an analysis of the device operation and electrolyte selection was performed. The two-electron oxygen reduction reaction (2e--ORR) using untreated gas diffusion electrode (GDE) was superior to the hydrogen evolution reaction (HER) using stainless-steel mesh in terms of cell voltage, product formation, and sulfide suppression. The GDE maintained a stable HO₂⁻ production capacity, achieving a concentration of 4566.6 ± 173.3 mg L⁻¹ with a current efficiency (CE) of 84.13 ± 3.5 %. During the electrolysis period, a stable dissolved oxygen (DO) level in sewage was consistently observed due to continuous in-situ oxygen production in anode. HO2- exhibited a notable increase in sewage pH (10.20 ± 0.01), effectively inhibiting the release of 99.93 % of sulfides. Moreover, the combined treatment of HO2- and DO significantly surpassed that of individual treatments. Seawater treated with cation exchange resin (CER) emerged as the most promising alternative to freshwater as the electrolyte. Overall, this study demonstrates that in-situ generation of HO₂⁻ and oxygen is a more effective strategy for sulfide control in sewer systems.

Enhanced Lithium Extraction from Brines: Prelithiation Effect of FePO4 with Size and Morphology Control.

Extracting lithium resources from seawater and brine can promote the development of the new energy materials industry. The electrochemical method is green and efficient. Iron phosphate (FePO4) crystal, with its 1D ion channel, holds significant potential as a primary lithium extraction electrode material. Li+ encounters a substantial concentration disadvantage in brines, and the co-intercalation of Na+ diminishes Li+ selectivity. To address this issue, this work enhances the energy barrier for Na+ insertion through prelithiation strategies applied to the 1D channels of FePO4 crystal, thereby improving Li+ selectivity, and further investigating the prelithiation effect with particle size and morphology control. The results indicate that the Li(4C-40%)FePO4// Activated carbon(AC) system enhances selectivity of lithium. The Li(4C-40%)FePO4 with size diameter of 2500nm demonstrates an energy consumption of 0.79Whmol-1 and a purity of 97.94% for lithium extraction at a unit lithium extraction of 5.93mmolg-1 in simulated brine. Li(4C-40%)FePO4-nanoplates demonstrate the most optimal lithium extraction performance among the three morphologies due to their lamellar structure's short ion diffusion path in the [010] channel, favoring Li+ diffusion. The diffusion energy barriers of Li+ and Na+ are calculated using Density Functional Theory (DFT) before and after prelithiation, showing good agreement with experimental results.