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This study investigates the effects of natural inhibitors (pomegranate, algae, and tomato extracts) on the corrosion resistance of titanium (grade 2). To deepen understanding the inhibition mechanism, Molecular Dynamic (MD) and Monte Carlo (MC) simulations were employed to analyze adsorption behaviors and identify optimal adsorption sites on titanium oxide (TiO2) surfaces for compounds within the inhibitors. Results indicate non-flat adsorption orientations, with pomegranate peel extract components showing superior inhibition capabilities, attributed to the formation of strong O-H chemical bonds with the TiO2 surface. In the experimental part of the study Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP) were conducted. Two electrolytes were tested: a solution 3.5% NaCl and a solution 0.5 M NaOH. All the tests were performed with 5% of inhibitor and with the reference solution. Also, inhibition efficiency was calculated on the base of PDP tests. The study found that pomegranate extract can act as a good corrosion inhibitor for titanium alloy in aqueous solutions 0.5 M NaOH. This was demonstrated by the increase in the corrosion potential and impedance modulus and decrease in the corrosion current density after the addition of pomegranate extract to the solution. However, in a 3.5% NaCl solution, the efficacy of pomegranate extract was less pronounced, probably due to the high aggressivity of the electrolyte. Tomato and algae extract have instead shown very low inhibition effects in all the tested conditions. [ABSTRACT FROM AUTHOR]

Chlorate (ClO3-) is a toxic oxyanion pollutant from industrial wastes, agricultural applications, drinking water disinfection, and wastewater treatment. Catalytic reduction of ClO3- using palladium (Pd) nanoparticle catalysts exhibited sluggish kinetics. This work demonstrates an 18-fold activity enhancement by integrating earth-abundant vanadium (V) into the common Pd/C catalyst. X-ray photoelectron spectroscopy and electrochemical studies indicated that VV and VIV precursors are reduced to VIII in the aqueous phase (rather than immobilized on the carbon support) by Pd-activated H2. The VIII/IV redox cycle is the predominant mechanism for the ClO3- reduction. Further reduction of chlorine intermediates to Cl- could proceed via VIII/IV and VIV/V redox cycles or direct reduction by Pd/C. To capture the potentially toxic V metal from the treated solution, we adjusted the pH from 3 to 8 after the reaction, which completely immobilized VIII onto Pd/C for catalyst recycling. The enhanced performance of reductive catalysis using a Group 5 metal adds to the diversity of transition metals (e.g., Cr, Mo, Re, Fe, and Ru in Groups 6-8) for water pollutant treatment via various unique mechanisms.

Photoelectrochemical (PEC) photodetectors convert light into electrical signals via PEC processes, providing high sensitivity, positioning them as promising candidates for next-gen optoelectronic devices. Over the past few years, there has been a significant interest in the field of photodetection regarding 2D materials, owing to their advantageous properties. In this study, the PEC photodetection of hydrothermally synthesized MoS2–Se nanocomposites have been systematically tested. Structural analysis confirms the coexistence of MoS2 and Se phases in the synthesized nanocomposites with crystallite sizes in the nanoscale dimension. Optical studies indicate that MoS2–Se nanocomposites exhibit broadened absorption spectrum extending to UV region, unlike pure MoS2 which absorbs solely in the visible region. This enhances their sensitivity for wide-band photodetectors with a small bandgap (1.01–1.34 eV). Optoelectronic study revealed superior performance of MoS2–Se thin film PEC device with efficient photoresponse with a responsivity of 38.3 μA/W and fast response time of 0.12 s. The novelty of this research resides in the integration of these unique features in MoS2–Se nanocomposites for PEC photodetectors, explored for the first time. The innovative aspect of this study involves employing spin coating to deposit 2D MoS2–Se thin films, which enhances control over film thickness and uniformity, thereby resulting in improved responsivity and photocurrent. [ABSTRACT FROM AUTHOR]

This study deals with the efficacy of extracts of Sargassum natans and Sargassum fluitans, an invasive brown algae present in Guadeloupe, as novel and environmentally friendly corrosion inhibitors for iron in 1 mol L−1 hydrochloric acid solutions. Six different Sargassum extracts (SE) were obtained using Soxhlet extraction with ethyl acetate, acetone, and ethanol, respectively, as solvents; cold successive maceration with chloroform and methanol, respectively; and microwave-assisted extraction with water. Subsequent electrochemical analysis showed that extracts from ethanol and ethyl acetate exhibited remarkable inhibition efficiencies of, respectively, 72.6% and 70.2%, but the better one was the extract of the cold maceration from chloroform with an inhibition efficiency of 92.0%. These findings allow us to focus on the chloroform extract (SEd) in order to see the change happening during the corrosion process via SEM and EDX analyses. Also, NMR analysis was conducted to identify the main chemicals responsible for the anticorrosion effect. The successful demonstration of the corrosion inhibitor effectiveness of extracts of Sargassum natans and fluitans suggests a potentially valuable use for this invasive biomass. These encouraging results warrant further investigation to identify and elucidate the active inhibitors in these extracts to deepen our understanding of their mechanisms for corrosion prevention and potentially expand their utility as an environmentally conscious approach to corrosion control. [ABSTRACT FROM AUTHOR]

Cobalt- and calcium-based metal–organic frameworks (Co-MOF and Ca-MOF) [Co (tpa) (Mi) and Ca (tpa)] (tpa = terephthalic acid and Mi = methyl imidazole) were synthesised through solvothermal method. Structural characterisation revealed that metal centres are equally occupied by Co2+ and Ca2+ ions. Supercapacitive behaviour of synthesised Co-MOF and Ca-MOF was evaluated using cyclic voltammetry (CV), galvanostatic charge/discharge, and electrochemical impedance spectroscopy (EIS) measurements in 6 M KOH as electrolyte. The Co- and Ca-MOFs exhibited outstanding specific capacitance of 1726 and 185 Fg−1 at a discharge current density of 1 Ag−1, good rate capability, and 97.4% capacitance retention after 3000 cycles. To the best of our knowledge, Co-MOFs and Ca-MOFs are used in supercapacitor, and their encouraging properties indicate that Co-/Ca-MOF can be a promising candidate as an advanced electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

An oversimplified corrosion inhibition experiment suitable for the laboratory practice for undergraduate students was developed. The different simplifications to the standard procedure of the corrosion inhibition experiment were tested. Using the examples of steel corrosion inhibition in sulfuric acid by sodium tungstate, and in hydrochloric acid by succinic acid, it was shown that the obtained results remain representative even if the experiment is performed very roughly and inaccurately. During the standard laboratory 3-hour session, both the gravimetric and electrochemical experiments in uninhibited medium with three different inhibitor concentrations could be performed by the students. The typical methodical instructions for the students and instructors were developed. The proposed laboratory experiment was tested during an academic year with the master-level students in Novosibirsk State University.

As a corrosion inhibitor for mild steel in a molar hydrochloric acid medium, we investigated the potential of Eucalyptus globulus essential oil (EuEO). Through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves, and theoretical methods, including DFT/B3LYP 6-31G (d, p) and Monte Carlo simulations, the interactions between the EuEO components and the steel surface were analyzed. D-Allose, Betulinaldehyde, and Uvaol were identified as the major active compounds in the GC-MS analysis. The experimental results showed that EuEO reached an inhibitory efficiency as high as 97% at a 1 g/L concentration. The findings suggest that EuEO operates as a mixed-type inhibitor, reducing both cathodic and anodic reactions, as well as building up a protective coating on the steel surface. Simulations also confirmed that EuEO molecules function as electron donors and acceptors, enhancing corrosion resistance. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WO3) is a well-known transition metal oxide that demonstrates stability and non-toxicity in its nanoparticle form. Because of its facile and cost-effective synthesis method, it is a promising candidate for several applications like electrochromic devices, photo catalysts and gas sensors. In the present work, WO3 nanoparticles were synthesized through a one-step hydrothermal process. Subsequently, the pure WO3 sample underwent doping with different materials, including Cr+ 3, Co+ 2, Ag+ 1, Hg+ 1 and Pb+ 4. The crystallographic properties and phase transitions of the crystalline substances were demonstrated by the structural characterisation of all the as-synthesised materials using the X-ray diffraction technique. The optical properties were explored by UV-visible spectroscopy, revealing the energy band gap from 2.53 eV to 3.75 eV. Field Emission Scanning electron microscopy (FESEM) images depicted the morphological features of the material. The pure WO3 exhibited a 2D nanosheet structure, while the doped materials displayed morphologies ranging from nanosheets or nanorods to polyhedral sheets. Microstructural analysis by TEM revealed particle size for all samples along with fringes and SAED pattern confirming the presence of respective planes. The electrochemical properties of the synthesized samples were investigated using Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV) techniques. This research delves into exploring the electrochemical sensing potential of tungsten oxide doped with chromium, cobalt, silver, mercury, and lead as thin layer working electrodes, driven by the pressing need for advancements in sensing technologies. Through a comprehensive investigation of their electrochemical and optical characteristics, this study aims to discern their suitability for sensing applications, providing insights crucial for future sensor design and synthesis. [ABSTRACT FROM AUTHOR]

The inhibitory properties of the Malus sylvestris flower and Syringa vulgaris flower boiling extracts against the stainless steel EN Fe37-3FN corrosion in 0.5 M sulphuric acid medium were studied using electrochemical methods, including open circuit potential measurement, potentiodynamic polarisation and EIS. The addition of 10 mg/l of the Malus sylvestris flower extract slows the corrosion by 15%, and that of of 10 g/l – by 65%, while the addition of 10 mg/l of the Syringa vulgaris flower extract slows the corrosion by 30%, and that of of 1 g/l and more – by 65%. The Langmuir absorption model describes the adsorption of the components of the extracts on a surface of the steel, and the adsorption is physical in its nature. The Malus sylvestris flower and Syringa vulgaris flower extracts reveal themselves as interesting and environmentally safe substances for the steel corrosion rate reduction in acidic environments. [ABSTRACT FROM AUTHOR]

Corrosion of mild steel is a disturbing phenomenon that deserves effective measures to avert accidents, equipment breakdown, and economic downturns. The corrosion inhibitory potentials of zinc oxide nanoparticles/tenofovir disoproxil fumarate nanocomposite (Z+D) was investigated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). PDP analysis revealed that the alteration in corrosion potential values in the presence of Z+D (compared to corrosion potential obtained in the absence of Z+D) was less than 85 mV which suggest that Z+D operated as a mixed-type inhibitor. Corrosion current density (Icorr) decreased tremendously from 1241 µAcm-2 (in the absence of Z+D) to 321 µA cm-2 in the presence of 1000 ppm of the inhibitor. The inhibition efficiency increased with an increase in concentration of inhibitor to reach 74% when 1000 ppm of the inhibitor was introduced. EIS studies revealed a tremendous increase in charge transfer resistance (Rct) from 3533 O cm2 (in the absence of the inhibitor) to 21464×cm2 when 1000 ppm of Z+D was introduced. The highest inhibition efficiency (i.e 84%) computed from EIS analysis was obtained when 1000 ppm of the inhibitor was introduced. Electrochemical findings suggest that Z+D exhibited good attributes as a corrosion inhibitor for mild steel in 1 M hydrochloric acid. [ABSTRACT FROM AUTHOR]

The inhibitory ability of the boiling extracts from the groats of Fagopyrum esculentum on the corrosion of mild steel EN Fe37-3FN in 0.5 M hydrochloric acid and 0.5 M sulphuric acid media was investigated using gravimetric, electrochemical, and EIS methods. It was shown that the addition of 100 mg/l of the Fagopyrum esculentum groat extract reduces the corrosion rate by 50%, and that of of 1 g/l and more – by 75%. The adsorption of the extract components on a steel surface follows the Langmuir adsorption model, and the nature of adsorption is physical. The Fagopyrum esculentum groats extract shows itself as perspective and environmentally friendly substance for reducing the steel corrosion rate in acidic environments. [ABSTRACT FROM AUTHOR]

AbstractThe development of an effective and economical anode is crucial for Al-air batteries. This article, describes the Al doped CdO nanomaterials that was created using the hydrothermal and sol-gel techniques, for optimization. The measurement of crystal size was done using X-ray diffraction. A scanning electron microscopy was used to examine the morphology of surfaces. The structure of the molecule and the strength of the link between Al doped CdO was revealed by the Fourier Transform infrared technique. Studies on electrochemical properties are determined by the voltammetry and GCD with a NaOH electrolyte. The electrochemical findings demonstrates that the sol-gel method used to prepared Al doped CdO had both oxidation and reduction peaks which indicates that this is one of the suitable electrode production method for an electrode in Al-air battery. The specific capacitance of the material synthesized was found to be the highest (289 F/g at 2 mA/g). [ABSTRACT FROM AUTHOR]

The synthesis and characterization of Imidazolium cation-based ionic liquids having different anions were reported in the present article. The physicochemical and spectral analyses were used to characterized these ionic liquids. The theoretical studies using the B3LYP method provide optimized structure, HOMO–LUMO plots, thermodynamic parameters, and quantum descriptors. The anti-corrosive property of Imidazolium cation-based ionic liquids was observed in 0.5 M H2SO4 corrosive medium at 303, 313, 323, and 333 K temperatures by various strategies like gravimetric studies, electrochemical impedance spectroscopy, potentiodynamic polarization studies, and scanning electron microscopy (SEM). The interesting feature of this article is that both ionic liquids follow different adsorption isotherms. IL-1 ionic liquid shows physisorption adsorption behavior, and IL-2 exhibits mixed adsorption (chemisorptions and physiorption). The electrochemical strategies and Egap value obtained from DFT reveal the maximum inhibition efficiency of IL-2 for the corrosion process in an acidic medium on mild steel. Potentiodynamic polarization studies reveal the mixed type behavior for ionic liquid inhibitors. EIS results indicate that the inhibition efficiency improved by enhancing ionic liquids concentration. The protective layer formation or adsorption of ionic liquid on metallic surface was confirmed by SEM. In the present article, the proposed mechanism shows the blockage of anodic and cathodic sites by ionic liquids to inhibit the corrosion process on mild steel in an acidic medium. [ABSTRACT FROM AUTHOR]

One of the factors that affect the performance of the value‐regulated lead acid (VRLA) battery is gel electrolyte. To address this, a gel polymer electrolyte comprising halloysite nano‐clay in a poly(vinyl alcohol) matrix is formulated and the electrochemical performance is studied. Interaction between halloysite nano‐clay and poly(vinyl alcohol) is confirmed by Fourier transform infrared spectroscopy (FTIR). To optimize the concentration of gel electrolytes, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) are utilized. Galvanostatic charge‐discharge (GCD) tests are performed on a prototype battery comprising of an optimized gel electrolyte. The battery shows the highest discharge capacity of 6.858 μAh at 7.5 μA cm−2 current density and achieves admirable discharge capacity retention of 87.5% after 500 cycles. Hydrogen‐bonded halloysite nano‐clay and poly(vinyl alcohol) can be employed as gel electrolytes in VRLA batteries. [ABSTRACT FROM AUTHOR]

Researchers have just discovered an alternative to synthetic corrosion inhibitors, which are hazardous and terrible for the ecosystem, to prevent rusting in the environment. A metal corrodes when it is subjected to corrosive media (acid, base, or saline) and they deteriorate, leading to failure. The most straightforward and affordable corrosion protection and prevention technique in acidic environments has been proven to be corrosion inhibitors. On industrial surfaces, pieces of machinery, or vessels, these inhibitors slow the rate of corrosion, preventing the monetary losses brought on by metallic corrosion. Recently, attention has been directed to developing ecologically appropriate corrosion retardation methods because inorganic and organic inhibitors are harmful and expensive. Recent studies have focused on green mild steel (MS) corrosion inhibitors that mimic industrial processes in acidic conditions. This presentation briefly covers the many types of corrosion, the corrosion process and the most recent studies on using natural plant extracts as corrosion inhibitors. Since they are safe and cost-effective, green corrosion inhibitors are a new trend in preventing corrosion. These inhibitors are produced from various plant parts, and inhibition efficiency (IE) also depends on them. To ascertain the IE of the corrosion inhibitor, some experiments, including computational studies (quantum calculations and MD simulations), electrochemical measurements (electrochemical impedance (EIS) and potentio-dynamic polarization), surface morphology atomic force microscopy (AFM), scanning electron microscopy (SEM)/energy-dispersive X-ray analysis (EDX) and UV–visible spectroscopy are carried out. It has been demonstrated that the IE is maximum for green corrosion inhibitors compared to synthetic inhibitors. This paper provides an overview of the properties, mechanism of corrosion inhibitors, nature of green corrosion inhibitors and their IE obtained by performing tests. This review article discussion shows that reinforcement with plant extract performs well in aggressive environments, which is evident from electrochemical studies and surface analysis when compared to reinforcement with inhibitors.

The fluorescence quenching studies using conducting polymers (CPs) have greatly contributed in the trace detection of high energy materials (HEMs) with nitro functional groups. Polyaniline doped with the anion surfactant sodium dodecyl sulfate (SDS) acts as a fluorophore and is used in fluorescence quenching studies to detect HEMs at trace levels. A mechanistic approach to understanding electron transfer during the interaction of fluorophore with HEMs were studied by using spectroscopic and electrochemical techniques. The presence of conjugation in conducting polymer shows a molecular wire effect during fluorescence quenching by trace level of HEMs by quenching several emissions in polymer chains. The Stern‐Volmer(S‐V) and limit of detection(LOD) plots give quenching mechanism and the efficiency of quenching. These values indicate that TNT had good sensitivity compared to other HEMs such as RDX, PETN, CL‐20 and CRCC. The FTIR and Raman studies were used to understand the interaction between nitro groups of HEMs with the benzenoid, polaronic and semi‐quinoid units of doped polyaniline. The cyclic voltammetry studies revealed shift in potential and current during the interaction of the fluorophore with HEMs, and these results were combined with fluorescence studies for better understanding of the possible mechanism of quenching. [ABSTRACT FROM AUTHOR]

The inhibitory effects of extracts from Phaseolus vulgaris and Vicia faba beans, obtained from boiled beans, on the corrosion of EN Fe37-3FN mild steel in a 0.5 M hydrochloric acid medium were meticulously investigated utilizing electrochemical techniques and Electrochemical Impedance Spectroscopy (EIS). The corrosion rate was observed to decrease by 40% upon the introduction of 20 mg/L of the Phaseolus vulgaris extract, with a notable reduction of 70% when the concentration was increased to 2 g/L and beyond. The Vicia faba extract, however, displayed a slightly inferior inhibitory performance, with corrosion rates diminishing by 20% at 20 mg/L and 60% at concentrations of 2 g/L and above. The adsorption of extract constituents onto the steel surface was found to conform to the Langmuir adsorption isotherm model, thereby facilitating the calculation of the sorption equilibrium constant and revealing that the adsorption was primarily physical in nature. These extracts, which are typically discarded by-products of bean cooking, have emerged as cost-effective, readily accessible, and environmentally benign alternatives for mitigating steel corrosion in acidic environments. [ABSTRACT FROM AUTHOR]

Researchers have just discovered an alternative to synthetic corrosion inhibitors, which are hazardous and terrible for the ecosystem, to prevent rusting in the environment. A metal corrodes when it is subjected to corrosive media (acid, base, or saline) and they deteriorate, leading to failure. The most straightforward and affordable corrosion protection and prevention technique in acidic environments has been proven to be corrosion inhibitors. On industrial surfaces, pieces of machinery, or vessels, these inhibitors slow the rate of corrosion, preventing the monetary losses brought on by metallic corrosion. Recently, attention has been directed to developing ecologically appropriate corrosion retardation methods because inorganic and organic inhibitors are harmful and expensive. Recent studies have focused on green mild steel (MS) corrosion inhibitors that mimic industrial processes in acidic conditions. This presentation briefly covers the many types of corrosion, the corrosion process and the most recent studies on using natural plant extracts as corrosion inhibitors. Since they are safe and cost-effective, green corrosion inhibitors are a new trend in preventing corrosion. These inhibitors are produced from various plant parts, and inhibition efficiency (IE) also depends on them. To ascertain the IE of the corrosion inhibitor, some experiments, including computational studies (quantum calculations and MD simulations), electrochemical measurements (electrochemical impedance (EIS) and potentio-dynamic polarization), surface morphology atomic force microscopy (AFM), scanning electron microscopy (SEM)/energy-dispersive X-ray analysis (EDX) and UV–visible spectroscopy are carried out. It has been demonstrated that the IE is maximum for green corrosion inhibitors compared to synthetic inhibitors. This paper provides an overview of the properties, mechanism of corrosion inhibitors, nature of green corrosion inhibitors and their IE obtained by performing tests. This review article discussion shows that reinforcement with plant extract performs well in aggressive environments, which is evident from electrochemical studies and surface analysis when compared to reinforcement with inhibitors. [ABSTRACT FROM AUTHOR]

The aim of this work is to develop new organic bio-sourced inhibitors that are ecofriendly and biodegradable. These natural inhibitors are organic, non-toxic molecules derived from plant extracts, containing numerous secondary metabolites, and are capable of being highly effective in protecting metals against corrosion. This study concerns the extraction, characterization and electrochemical study of natural organic compounds extracted from a species of Sargassum abundant on the coasts of Martinique, Sargassum fluitans III. The objective is to inhibit the corrosion of carbon steel. Electrochemical impedance spectroscopy (EIS) and linear polarization (LP) techniques have led to new experimental results showing inhibitor efficacy. The results obtained show that this plant extract could serve as an effective inhibitor for the C38 steel in acidic media. Studies on the phytochemicals of the crude extract were also carried out. Electrochemical studies, on each chemical families present, were also established to find the main constituents responsible for corrosion inhibition properties of the algae extract. The adsorption of Sargassum fluitans III extract on the C38 steel surface, obeys the Langmuir adsorption isotherm. [ABSTRACT FROM AUTHOR]

In this paper, we compared the corrosion inhibiting effect of two essential oils on mild steel in 1 M HCl. The essential oils are extracted from natural plants harvested in Morocco and prepared through distillation. To carry out this work, we used gravimetric and electrochemical methods, including current-potential plots and impedance spectroscopy. The results obtained show that both essential oils are a good corrosion inhibitor and that the inhibition efficiency of wormwood essential oil reaches a value of more than 80 % at 298 K. To learn the fundamentals of how inhibitors interact with metal surfaces, wormwood essential oil adsorption on a mild steel surface was also investigated. The Langmuir isotherm model is revealed to be how the essential oils adsorb on the metal surface. The effect of temperature on the performance of mild steel in 1 M HCl with wormwood essential oil was examined in the temperature range of 313 to 353 K. Additionally, calculations and discussions are made to provide some thermodynamic data for the adsorption processes. This work enters the framework for the use of non-toxic products in green chemistry. [ABSTRACT FROM AUTHOR]

Catalytic activities of oxidation on hydrazine and azo-dye are a problem, and greenly synthesized nanoparticles (NPs) have emerged as an inventive and potential remedy. The unique nano-specific characteristics of palladium nanoparticles (Pd-NPs) provide significant therapeutic prospects. The current work shows the one-pot bioactive manufacture of palladium nanofillers using a straightforward method based on leaf extractions from Cinnamomum camphora. Nanomaterials made of palladium are excellent catalysts. Its combination has drawn a lot of interest, and the knowledge about these traits is growing. Microbial methods may make palladium nanoparticles, which may be more ecologically friendly. According to high propagation electron microscopy, energy dispersive spectrometry, and X-ray diffraction (XRD) examination, this one is shaped like a circle and has a cubic head symmetry. According to optical microscope measurements, palladium nanomaterials have modest particle sizes, with a mean range of 22.50 nm. Palladium nanoparticles may be made via this approach, which is affordable, safe, and very successful. In the electrical oxygenation of hydrazine and the enzymatic lowering breakdown of p-amino azobenzene, a carboxylate prototype product, palladium nanoparticles exhibit intense anti-oxidant activity. This gradual increase in oxidant activity points to a slower reaction time. The flow of the oxide layer at the platinum and graphite sheets dramatically rises at 0.084 V whenever the voltage sweeps higher at 0.5 V. The signal at 381 nm fading after 30 s further suggests that palladium nanoparticles colloidal were used to achieve a higher breakdown of p-amino azobenzene (pAAB). Furthermore, amitriptyline and p-phenylenediamine absorbance rose at 230 nm, and a new album developed at 315 nm, respectively, which can be attributed to these substances. The stability and reusability of biosynthesized NPs were confirmed through Suzuki–Miyaura coupling reaction. [ABSTRACT FROM AUTHOR]

The influence of sulfate-reducing bacteria Desulfovibrio desulfuricans on stainless steel SS 202 corrosion in neutral media was studied in detail using weight loss and electrochemical routes. The bacterial activity resulted in material loss with an average rate of 0.015 mm/year. The scanning electron microscopy (SEM) analysis showed a significant increase in the sessile bacterial population with the immersion period. Use of 500 ppm palash (Butea monosperma) leaf extract (PLE) reduced the average corrosion rate to 0.002 mm/year. SEM analysis showed a very thin external film formation in the presence of the inhibitor. The X-ray photoelectron spectroscopy studies confirmed the presence of corrosion products such as Fe2O3 and FeS. The gas chromatography–mass spectrometry studies showed the dominant percentage of various terpenoids along with vitamin E as the main components of the PLE. Electrochemical analysis showed the existence of a diffusion barrier. The resistance offered by the diffusion barrier is high in the inhibited sample when compared to uninhibited samples.

[Display omitted] Reversible transformations of a hybrid molecule based on [60]fullerene and a spiropyran moiety under conditions of combined photo- and electrochemical exposure were found. It has been established that the electrochemical oxidation of the UV-photoinduced colored form of the hybrid spiropyran in solution significantly accelerates the discoloration process and does not affect the fullerene part of the hybrid molecule. The research results are promising for designing a photo-electrochromic device that modulates electromagnetic radiation in the visible range of the spectrum. [ABSTRACT FROM AUTHOR]

In the present work, we have synthesised silver nanoparticles (Ag NPs) using the leaf extract of Ficus religiosa. The Ag NPs were incorporated with biochar (derived from algal biomass powder) and used as an electrode material for supercapacitors. The presence of different phytochemicals in the leaf extract of Ficus religiosa was confirmed using different phytochemical tests. The prepared nanocomposite (Biochar/Ag) was analysed using different analytical methods. Galvanostatic charge–discharge, electrochemical impedance analysis, and cyclic voltammetry have all been used in the electrochemical investigation. The maximum specific capacitance of Biochar/Ag was calculated to be 675 F/g. The cyclic stability of Biochar/Ag was observed to be 96.1% after 5000 GCD cycles under three electrode systems. The maximum power density of Biochar/Ag has been found to be 3168 W/kg. The developed Biochar/Ag can be utilised as an effective and low-cost electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

A magnetic mixed iron oxide, magnetite (Fe3O4), was synthesized in the laboratory and characterized before its use as sorbent for arsenic removal. The characterization techniques used were X-ray diffraction (XRD), specific surface area, zeta potential and particle size measurements. The sorbent was applied for arsenic removal, without any pre or post treatment, from groundwater. The efficiency of sorption can only be improved by understanding the sorbent–sorbate interaction. For onsite monitoring of the sorbent-sorbate interaction, an electrochemical investigation using cyclic voltammetry (CV) measurement was developed. The study confirmed that the sorption of As(III) on Fe3O4 is dynamic (reversible) whereas that of As(V) is static (irreversible) in nature. Detailed investigation after the sorption was carried out utilizing X-ray photoelectron spectroscopy (XPS) measurement. The complexation of As(III)-Fe3O4 and As(V)-Fe3O4 without any redox transformation was evident from the XPS data. By careful examination of the results, a mechanism of arsenic removal by Fe3O4 was proposed. [ABSTRACT FROM AUTHOR]

In this article, we examine the effects of Sm substitution by Zn on the structures and electrochemical characteristics of SmxZn1−xFe2O4 alloys prepared by sol–gel technique. The structural properties of the electrodes are studied by X‐ray diffraction and scanning electron microscope (SEM). The structural properties of these alloy are well influenced by the substitution rate. The SEM images of the powder of all samples (x = 0, 0.2, 0.4, and 0.6) shows the presence of agglomerates in the powder particles. Moreover, EDX investigation demonstrates that the chemical and theoretical compositions of all the prepared alloys are almost the same. The electrochemical performance of the oxide electrodes was analyzed at temperature 298 K using chronopotentiometry, chronoamperometry, and cyclic voltammetry techniques. During the first cycles, the electrochemical discharge capacity increases for all alloys. Obviously, this evolution is rapid for the unsubstituted alloy, but it becomes slower by increasing the substitution rate. The highest discharge capacity value was obtained for the ZnFe2O4 electrode of the order of 180 mAh/g while the highest retained capacity was observed for the Sm0.6Zn0.4Fe2O4 electrode. The kinetic results showed that the exchange current density I0 and the hydrogen diffusion coefficient DH of the anodes increased with increasing substitution rate and the best values were obtained for the Sm0.6Zn0.4Fe2O4 anode. [ABSTRACT FROM AUTHOR]

Corrosion of Aluminum metal at pH 10 has been controlled by dicarboxylic acids such as oxalic acid (OA) and adipic acid (AA).The Inhibition efficiency (IE) has been determined by the classical weight loss method. The maximum inhibition efficiency (IE) offered by the oxalic acid (OA) and adipic acid (AA) 250 ppm and Zn2+ 50 ppm system are 88 and 96%. To determine the values of Linear Polarization Resistance (LPR) and corrosion Current (Icorr), potentiodynamic polarization study has been used.

This present work aims to investigate the influence of organic dyes (methyl orange (MO), hexamethyl pararosaniline chloride (HPC)) doped with potassium hydrogen phthalate ammonium sulfate (KHPA) crystals. The solution-grown dye doped KHPA were examined using powder-XRD, FT-IR, UV–visible spectroscopy, dielectric, microhardness, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and antibacterial activity studies. PXRD spectrum revealed that the solution-grown crystal belongs to orthorhombic system with excellent cell parameters. The grain size of the dye doped KHPA crystal was found to be D = 26.609 nm. The FTIR spectral analysis was identified the presence of various functional groups and the UV spectrum showed absorbance around 280 nm for the solution-grown dye doped crystals of KHPA. The Tauc's plots of pure KHPA exhibited band gap energy of 4.5 eV, whereas the band gap energies of MO and PHC doped KHPA crystals showed 4.25 eV and 4.13 eV, respectively. Thermal stability of the as-grown dye doped KHPA crystals was analyzed by TGA and DTA techniques. The dielectric study revealed that the dielectric constant and dielectric loss decreased while increasing the frequency, whereas the microhardness study showed that the dye-doped crystals belong to the soft material category. CV of dye-doped crystals exhibited a strong reduction potential wave at − 0.75 V for HPC doped KHPA and − 0.6 V for MO doped KHPA. EIS study exhibited the decrease in impedance with change in frequency indicating a negative temperature coefficient of resistance and low ion mobility of the dye doped KHPA crystals. The antibacterial study revealed that the Gram-negative bacteria have more resistivity than Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

Bismuth sulfide (Bi2S3)-sensitized titanium dioxide (TiO2) nanorods have been successfully synthesized by a simple and cost-effective chemical deposition method onto the conducting glass substrates. Bi2S3 nanoparticles are sensitized over the hydrothermally grown TiO2 nanorods by using successive ionic layer adsorption and reaction (SILAR) method. The structural, morphological, optical, and electrochemical studies were carried out using X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible–near infrared (UV–Vis–NIR) spectroscopy, electrochemical impedance spectroscopy (EIS), etc. XRD pattern reveals the formation of pure rutile tetragonal TiO2 with orthorhombic Bi2S3 crystal structure. SEM images show the formation of Bi2S3-sensitized TiO2 nanorods. The diameter of the nanorods is ~ 250 nm, and the size of Bi2S3 nanoparticles is ~ 100 nm. The films show hydrophilic nature which is beneficial for the photoelectrochemical performance of the photoanodes. The optimized photoanode shows an improved short-circuit photocurrent density of 421 µA/cm2 with a power conversion efficiency of 0.06% in polysulfide electrolyte. [ABSTRACT FROM AUTHOR]

This study delves into the mechanistic roles of oxidants, complexing agents, and inhibitors in slurries through of Distribution of Relaxation Times (DRT) analysis. The influence of varying concentrations of these chemicals on electrochemical processes is discussed. This article divides the spectrum obtained through DRT analysis into four different frequency regions and differentiate naming through electrode reaction process: the double-layer charging step, the charge transfer step, the mass transfer step, and the surface transformation step by adsorption or chemical alterations at the electrode surface. The results reveal that the peak observed in the low-frequency range at 10−2–10° Hz is associated with mass transfer step, while the relaxation peak at 10°–102 Hz corresponds to the charge transfer process, while the relaxation peak occurring at 102–104 Hz is linked to the surface transformation step, and the first peak emerging in the 104–106 Hz range is attributed to double-layer charging step. [Display omitted] [ABSTRACT FROM AUTHOR]

The present article involves synthesis of graphene oxide functionalized silatrane for the electrochemical detection of acetaminophen. [Display omitted] • Graphene oxide functionalized silatrane (GO-Silatrane) based sensor has been synthesized. • Electrochemical study of the prepared probe shows sensitive and selective attraction towards acetaminophen. • GO-Silatrane/GCE shows excellent reproducibility and repeatability. • The practical applicability of the receptor has been checked by detecting it in pharmaceutical tablets. Acetaminophen, commonly known as paracetamol, is a widely used analgesic and antipyretic drug that is frequently found in over-the-counter and prescription medications. Due to its extensive use, precise monitoring of acetaminophen levels is crucial for ensuring patient safety, especially to prevent accidental overdoses which can lead to severe liver damage. In this study, a novel electrochemical sensor based on graphene oxide (GO) functionalized with silatrane was developed for the detection of acetaminophen. The hybrid material was synthesized and electrodeposited on a glassy carbon electrode, providing a highly selective, sensitive, and reproducible platform for acetaminophen detection. The sensor exhibited a linear detection range from 2.5 to 100 μM with a limit of detection of 84.8 nM. The effectiveness of this GO-based sensing platform was demonstrated through the successful quantification of acetaminophen in pharmaceutical tablets such as Dolo 650, Paracip, and Crocin. The results highlight the potential application of this sensor in quality control and safety monitoring of pharmaceutical formulations, ensuring accurate determination of acetaminophen content. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are promising electrode materials however, they continue to seek improvements in both energy density and electrical conductivity. Within a wide array of available metal nodes and linkers, the task of refining and attaining a profound comprehension of charge storage mechanisms is still to accomplish. Herein nickel sulfide and nickel MOF were synthesized via hydrothermal method, their properties were investigated, and a binary composite was developed due to the high resistance of pristine MOFs. This composite demonstrated exceptional specific capacity of 787.8 C/g at cost of 2.0 A/g. To leverage real-world applications, a supercapattery was fabricated using the NiS/Ni-MOF as the positive electrode material and activated carbon as the negative electrode material. The device possesses maximum specific energy of 64.67 Wh/kg and maximum specific power of 3200 W/kg together with capacity retention of 91 % after 5k charge-discharge cycles. To validate results, semi-empirical approach using Dunn's model and power law is subjected to investigate the capacitive and diffusive contributions and b-values. This study shows that the binary composites of metallic sulfides with MOFs can possess potentials for their applications in real devices. • To synthesize NiS and Ni-MOF through facile hydrothermal route. • Conducted a thorough study of the surface, structural, and electrochemical properties of both samples. • Overcoming the individual shortcoming of both material by making a binary composite of NiS/Ni-MOF. • Fabricating a hybrid device by employing NiS/Ni-MOF and activated carbon. • Achieved a maximum specific energy of 64.67 Wh/kg and a maximum power delivery of 3200 W/kg in the fabricated device. [ABSTRACT FROM AUTHOR]

The hull plates of the ship made of mild steel (MS) are always in contact with seawater are always in contact with aggressive ions such as chloride ions present in seawater.The corrosion resistance of the hull plates of the ship made of mild steel has been investigated by polarization study. Sandalwood oil extract containing 5 g each of Cardamom (disambiguation), Clove (disambiguation), Nutmeg, India Sambrani (loban), Chrysopogon zizanioides, commonly known as vetiver and Camphor was used as corrosion inhibitor along with Trisodium citrate (TSC), sodium dihydrogen phosphate (SDP) and Zn2+. The corrosion resistance was measured in the absence and presence of various inhibitor systems: Trisodium citrate (TSC) 100 ppm+ Zn2+ 50ppm system, sodium dihydrogen phosphate (SDP) 100 ppm+ Zn2+ 50ppm system, Oil coated (3days) MS, Oil coated (3days) MS +TSC 100 ppm+ Zn2+ 50 ppm system and Oil coated (3days) MS +SDP100 ppm+ Zn2+ 50 ppm system were used. It is observed that when mild steel is immersed in SW+TSC 100 ppm+ Zn2+ 50ppm system , the corrosion resistance of MS increases. When mild steel is immersed in SW+ SDP 100 ppm+ Zn2+ 50ppm system , the corrosion resistance of MS increases. When mild steel is immersed in Oil coated (3days) MS in Sea water system , the corrosion resistance of MS increases. When mild steel is immersed in Oil coated (3days) MS in SW+TSC 100 ppm+ Zn2+ 50ppm system , the corrosion resistance of MS increases. When mild steel is immersed in Oil coated (3 days) MS in SW+ SDP 100 ppm+ Zn2+ 50ppm system , the corrosion resistance of MS increases. This is revealed by the fact that there is increase in LPR value and decrease in corrosion current value. The corrosion potential is shifted to anodic side. This indicates that in this inhibitor system, the anodic reaction of metal dissolution is controlled predominantly. This implies that these inhibitor systems may be coated on mild steel surface used as hull plates to prevent corrosion of mild steel in sea water.

The inhabitation behavior of adenine for 304 and 316 stainless steels (SS) in 1 N hydrochloric acid solution at ambient temperature was studied using weight loss, electrochemical methods and surface characterization. Result showed the corrosion rate of stainless steel significantly is reduced by addition of 70 mg/L adenine with maximum inhibitation efficiency of 83 and 65 percent for 304 and 316 SS, respectively. The potentiodynamic investigation demonstrated the studied inhibitor acting as a mix type inhibitor with the predominant of anodic inhibitation. EIS studies indicated a main increase in polarization resistance after adenine addition. The surface morphology and EDS analysis of specimens after exposure to acidic solution with and without inhibitor exhibited the material surface are protected by formation of protective film layer. Adsorption of adenine inhibitor on 304 and 316 SS was found in accordance with Langmuir adsorption isotherm, and isotherm parameters including Kads and ΔGads0 were determined in ambient temperature. [ABSTRACT FROM AUTHOR]

This work aims to valorize the waste of Citrus reticulata fruit (aqueous extract of peels and leaves of Mandarin fruit) by investigating them as novel environmentally friendly inhibitors for scales formed by deposits from Bounouara hard ground water. To carry out this study, the physico-chemical quality of Bounouara water was investigated, and the scaling power of Bounouara raw water and the anti-scaling effect of Citrus reticulata waste were analyzed by chronoamperometry measurements. The formed tartar layers on the stainless steel (SS) electrode surface were characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and X-rays diffraction analyses. The Chronoamperometric study proved that the raw water of Bounouara is classified as a very scaling water, whereas the (SS) electrode surface was totally covered by CaCO3, CaSO4, and CaPO3 (OH) crystals. The anti-scaling properties study of Citrus reticulata waste showed that the effect of bio-inhibitors starts at very low concentrations, and a complete scaling inhibition was obtained with a concentration of 50 ppm of peels aqueous extract (CRP) and with 75 ppm of leaves aqueous extract (CRL) at 20 °C. However, 25 ppm of peels or leaves aqueous extract were sufficient to inhibit the scaling deposits and prevent the calcite and gypsum growth for Bounouara water. [ABSTRACT FROM AUTHOR]

This work reports urea as a promising complexing agent in sodium carbonate-based alumina slurry for chemical–mechanical planarization (CMP) of tantalum and copper. Ta and Cu were polished using Na2CO3 (1 wt. %) with alumina (2 wt. %) in the presence and absence of urea. The effect of slurry pH, urea concentration, applied downward pressure and platen rotational speed were deliberated and the outcomes conveyed. Prior to the addition of urea, the Ta removal rate (RR) was observed to increase with pH from acidic to alkaline, having a maximum RR at pH 11. However, Cu RR decreases with increasing pH with minimum RR at pH 11. With the addition of urea in the slurry, a Cu to Ta removal rate selectivity of nearly 1:1 was encountered at pH 11. The addition of urea simultaneous boosts the Ta RR and suppresses Cu RR at pH 11, as it adsorbs on the metal surface. Potentiodynamic polarization was conducted to determine the corrosion current (Icorr) and the corrosion potential (Ecorr). Electrochemical impedance spectroscopy of both metals was carried out in the proposed formulation and the obtained outcomes are elaborated.

Thiophenol (HLH), 4-methylthiophenol (HLMe) and 4-chlorothiophenol (HLCl) react with dirhenium(III,II) complex [Re2(µ-O2CCH3)Cl4(µ-dppm)2] (1) (dppm = Ph2PCH2PPh2) in refluxing dry toluene to afford the diamagnetic Re26+ complexes of the type [Re2(μ-LR)2Cl4(μ-dppm)2] (2(LR)) [LR = C6H5S–, p-MeC6H4S– and p-ClC6H4S–]. These are the first examples of thiophenolato bridged dirhenium complexes with a Re26+ core containing dppm ligand. The spectral properties of the complexes are reported. In the electrochemical experiment, the type 2(LR) complexes show one quasi-reversible one-electron oxidation and one-electron reduction waves. The identity of 2(LMe) has been established by single-crystal X-ray structure determination (Re–Re distance = 2.6178(5) Å) and is shown to have an edge-shared bi-octahedral structure. DFT analysis shows that the highest occupied molecular orbitals are mainly composed of metal δ-based orbitals whereas the lowest unoccupied molecular orbitals are metal π*-based orbitals and the electronic ground state for the 2(LR) complexes is σ2π2δ*2δ2. Time-dependent DFT (TD-DFT) analysis shows that the sharp peak at 455 nm in the experimental UV-vis spectrum is mainly due to the [Cl(π)]→[Re2(π*)] transition. [ABSTRACT FROM AUTHOR]

Nowadays, application of Ni–Ti alloys is receiving a great interest because of their premium hardness, wear, and corrosion resistance properties. Anti-corrosive Ni–Ti alloy coatings were fabricated by electrodeposition technique. The bath constituents and electrodeposition conditions have been optimized by the Hull cell technique. The surface features of the Ni–Ti alloy coating were analyzed with Scanning electron microscopy (SEM) along with Energy dispersive x-ray spectroscopy (EDX) depicting the presence of Ti, C, Ni, and O elements in the deposit. The phase structure of the alloy coating at different current densities was studied with X-ray diffraction spectroscopy (XRD). The micro-hardness of the coating film was measured by Vicker's micro-hardness tester and the maximum value was found to be 136 HV0.5 at optimal current density (4 A/dm2). The potentiostatic polarization and electrochemical impedance spectroscopy measurements were used to determine the corrosion properties of the Ni–Ti coating films. New low-cost sulphate bath has been proposed for uniform Ni–Ti alloy coating and the results indicate greater corrosion resistance properties, and these coatings can be used for biomedical, electronics and aerospace industries. [ABSTRACT FROM AUTHOR]