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Comprehensive Summary: The concurrent implementation of cascade reactions that combine biocatalysis and chemocatalysis is a challenging undertaking. Electrocatalysis provides versatile catalytic abilities and allows for mild reaction conditions, offering the potential for designing concurrent chemoenzymatic cascade reactions. The research on bioelectrocatalysis has primarily concentrated on utilizing electrocatalysis to achieve cofactor regeneration of enzymes. In contrast with previous reports, herein, we developed a deracemization strategy involving the concurrent combination of biocatalytic reduction and anodic oxidation in an undivided cell to achieve chiral sulfoxides, demonstrating the good compatibility. We anticipate this study will offer an alternative pathway for the design of the cascade reaction combined with electrocatalysis and biocatalysis. [ABSTRACT FROM AUTHOR]

The high oxidation potential of Au(I)/Au(III) redox couple renders the development of gold‐catalyzed cross‐coupling reactions highly challenging. In the pursuit of Au(I)/Au(III) redox catalysis, various strategies, such as the use of stoichiometric oxidants, merged gold/photoredox systems, or ligand‐enabled approaches, have been adopted to achieve the oxidation of Au(I) to Au(III) complexes. Recently, electrochemical anodic oxidation‐based gold redox catalysis has emerged as a new technique to facilitate gold‐catalyzed cross‐coupling reactions. This concept article provides a succinct overview of electrochemical gold redox catalysis, highlighting the challenges and potential future developments. [ABSTRACT FROM AUTHOR]

Titanium alloys, with the high specific strength and low elastic modulus, are currently the research focus of many applications. Various surface treatments have been applied with the intention of improving their wear and corrosion resistance. Micro-arc oxidation (MAO) technology originated from anodic oxidation (AO) technology, which has the advantages of simple process, high efficiency and environmentally friendly electrolyte. However, due to the micro-arc discharge effect, MAO coatings inevitably show the characteristic of high porosity. In this study, post-treatment of MAO coatings using AO was proposed to obtain a composite coating with both high hardness and low roughness and porosity thereby compensating for the defects of MAO coatings. After preparation, each sample was analyzed and characterized. The results indicated that AO was main conducted in the discharge channel of MAO coating and an amorphous phase coating with the matrix oxide as main component was grown in situ. The composite coating showed a slight increase in thickness and significant reduction in roughness than MAO coating and with superior wear and corrosion resistance. In conclusion, this study provides new idea and data support for improving the performance of MAO coatings, which is expected to be widely used in the field of surface treatment. [ABSTRACT FROM AUTHOR]

Fluoxetine (FLX) is a selective serotonin reuptake inhibitor (SSRI) medication commonly used to treat mental health disorders, but it can be harmful to the environment if not properly disposed of due to incomplete metabolism. In this study, electrochemical anodic oxidation with mixed metal oxide anodes was studied as a method to remove FLX from water and wastewater. Iridium dioxide-coated titanium (Ti/IrO2) and ruthenium dioxide-coated Ti (Ti/RuO2) electrodes were found to be more effective than platinum-coated Ti (Ti/Pt) electrodes, with removal efficiencies of 91.5% and 93.9%, respectively. Optimal conditions for FLX removal were determined to be an applied current of 150 mA, initial pH of 5, and oxidation time of 120 min. The rate of FLX degradation (kFLX) for the Ti/Pt, Ti/IrO2, and Ti/RuO2 electrodes were determined to be 0.0081 min−1 (R2:0,8161), 0.0163 min−1 (R2:0,9823), and 0.0168 (R2:0,9901) min−1 for 25 mg/L initial FLX concentration, respectively. The kFLX values varied based on the initial FLX concentration and decreased as the initial FLX concentration increased. The specific energy consumption (SEC) after 120 min of operation was 51.0 kWh/m3 for the Ti/Pt electrode, 39.6 kWh/m3 for the Ti/IrO2 electrode, and 48.6 kWh/m3 for the Ti/RuO2 electrode under optimised conditions. Overall, electrochemical anodic oxidation is an effective method for removing FLX from water and wastewater, with Ti/IrO2 and Ti/RuO2 electrodes providing superior performance compared to Ti/Pt electrodes. [ABSTRACT FROM AUTHOR]

New anodes consisting of zirconium-doped PbO2 coating, growth on titanium dioxide interlayer, were deposited on titanium substrates using spin coating method and have been tested for the removal of ampicillin, a β-lactam antibiotic, from water. Morphological, structural, and electrochemical properties of the prepared coatings were characterized by scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), and electrochemical impendence spectroscopy (EIS). Results showed that the incorporation of zirconium dopant had a noticeable modification in the morphology of anodes. An increase in the surface roughness and the specific active area were observed with Ti/TiO2/PbO2- 10% Zr electrode compared to other anodes. The electrochemical measurements indicated that the anode doped with 10% Zr showed a more protective coating performance than the undoped and 20% Zr-doped PbO2 electrodes. The experiments on ampicillin degradation revealed that doped lead dioxide anodes have excellent electrocatalytic activity. The major byproduct generated during anodic oxidation treatment has been identified as ampicilloic acid by liquid chromatography-mass spectroscopy (LC–MS) analysis. Results demonstrated that Ti/TiO2/PbO2- 10% Zr anode presents the best removal rate of ampicillin with a minimum intermediate amount, which leads to conclude that 10% is the optimum percentage of zirconium dopant for antibiotic wastewater treatment. [ABSTRACT FROM AUTHOR]

This research investigates the utilization of a modified Ti/nano ZnO-Bi2O3 electrode for the electrochemical advanced oxidation-based removal of a pharmaceutical pollutant from an aqueous solution. To analyze the surface properties of Ti/nano ZnO, Ti/nano Bi2O3, and Ti/nano ZnO-Bi2O3 electrodes made using electrophoretic deposition, various analytical methods were used. These methods included X-ray diffraction analysis, energy-dispersive spectroscopy, and field emission scanning electron microscopy confirmed the presence of ZnO nanoparticles and Bi2O3 nanoparticles in a layer that is uniformly coated on the Ti/nano ZnO-Bi2O3 electrode. Beside linear sweep voltammetry and Tafel plots confirmed the increased stability and electrocatalytic activity of the modified electrode compared to the initial electrode. Chronopotentiometry and chronoamperometry verified the stability and better conductivity of the nanocomposite electrode, and according to electrochemical impedance spectroscopy, charge transfer in the modified electrode has improved by 87%. We evaluated the effectiveness of the Ciprofloxacin removal process by considering factors, such as pH in the range of 3–11, electrolyte concentration in the range of 1–7 g L−1, and current density in the range of 1.2–5.75 mA cm−2. We selected Ciprofloxacin as the specific pollutant for evaluating pollutant removal from aqueous solutions due to its widespread use and presence in the environment. We determined the optimal parameter values to be 6.25 mA cm−2, 5, and 3 g L−1. Under these optimal conditions, the efficiency of ciprofloxacin removal reached 96.33% within 300 min. [ABSTRACT FROM AUTHOR]

Anodic oxidation–promoted SNAr reactions of electron-rich aryl fluoride were developed. The anodic oxidation of 4-fluoroanisole in hexafluoroisopropyl alcohol (HFIP) with K2CO3 led to SNAr-type hexafluoroisopropoxylation, and the reaction was completed with a catalytic electrical input. The results of cyclic voltammetry suggest that the radical cation of 4-fluoroanisole, which would react with the alkoxide of HFIP, is generated. Electron transfer between the intermediate and the starting material constructs the catalytic cycle, and the elimination of fluoride from the Meisenheimer complex produces the desired compound. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ammonia removal from wastewater by electrooxidation (EO) is an interesting approach because of its efficiency and easy maintenance and operation. In this process, ammonia is oxidized to nitrate or nitrogen gas. Ammonia conversion to the latter is desirable to remove nitrogen from the liquid; however, the influence of several operating parameters on nitrate generation has not been systematically evaluated. Therefore, this work aimed to investigate the effect of current density (200–800 A m−2), chloride concentration (0–10 000 mg L) and initial pH (5–9) on the electrooxidation of an ammonia‐containing solution and the associated generation of nitrate. For this purpose, a laboratory‐scale electrochemical reactor containing two Ti/RuO2 electrodes was used. RESULTS: The results indicated high ammonia removal efficiency – 98% within 150 min at 800 A m−2 and 97% within 240 min at 500 A m−2 – generating around 70 and 102 mg NO3−‐N L−1 under these conditions, respectively. Increasing the chloride concentration from 5000 to 7500 mg L−1 reduces the electrolysis time needed to remove all ammonia from 180 to 150 min. However, with increasing initial chloride concentration, the amount of nitrate generated rose from 69.5 to 135.9 mg N L−1. On the other hand, in the test without chloride, nitrate generation was considerably lower (0–0.61 mg L−1). CONCLUSION: The higher the current density applied, the greater the ammonia removal by EO. Although current density influenced the ammonia oxidation rates, it did not directly affect nitrate formation. The lower the concentration of ammonia in the solution, the more significant was the fraction of nitrate generated. Most of the inlet ammonia was oxidized to nitrogen gas, nitrite was rapidly oxidized to nitrate and higher chloride concentrations enhanced ammonia oxidation. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

This Minireview examines a selection of case studies that showcase distinctive and enabling electrochemical approaches that have allowed for the generation and reaction of carbocation intermediates under mild conditions. Particular emphasis is placed on the progress that has been made in this area of organic synthesis and polymer chemistry over the past decade. [ABSTRACT FROM AUTHOR]

Featured Application: Our results demonstrate the easy and accurate control of the amount of active ingredient relative to its degradation product in waste water treatment materials containing ferrate(VI). Potassium ferrate(VI) (K2FeO4) as a particularly strong oxidant represents an effective and environmentally friendly waste water treatment material. When produced by anodic oxidation in highly alkaline aqueous solution, the K2FeO4 product is separated and sealed in inert plastic bags with the retention of some liquid phase with high pH. This method proved to be excellent for long-term storage at moderately low temperature (5 °C) for industrial applications. It is still imperative to check the ferrate(VI) content of the product whenever it is to be used. Fe-57 Mössbauer spectroscopy is an excellent tool for checking the ratio of ferrate(VI) to the degradation product iron(III) in a sample. For this purpose, normally the spectral areas of the corresponding subspectra are considered; however, this approximation neglects the possible differences in the corresponding Mössbauer–Lamb factors. In this work, we have successfully determined the Mössbauer–Lamb factors for the ferrate(VI) and for the most common iron(III) degradation products observed. We have found superparamagnetic behavior and low-temperature phase transformation for another iron(III) degradation product that made the determination of the Mössbauer–Lamb factors impossible in that case. The identities of a total of three different iron(III) degradation products have been confirmed. [ABSTRACT FROM AUTHOR]

Yu Pan,1,* Lili Cao,2,* Libing Chen,1,* Linjuan Gao,2 Xia Wei,1 Honglei Lin,1 Lei Jiang,1 Yinghui Wang,1,2 Hui Cheng1,2 1Department of Prosthodontics, Institute of Stomatology & Research Center of Dental Esthetics and Biomechanics, School and Hospital of Stomatology, Fujian Medical University, Fuzhou, Fujian, People’s Republic of China; 2Department of Prosthodontics, Fujian Key Laboratory of Oral Diseases & Fujian Provincial Engineering Research Center of Oral Biomaterial & Stomatological Key Laboratory of Fujian College and University, School and Hospital of Stomatology, Fujian Medical University, Fuzhou, Fujian, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yinghui Wang; Hui Cheng, School and Hospital of Stomatology, Fujian Medical University, Fuzhou, Fujian, People’s Republic of China, Email wyh9519@fjmu.edu.cn; ch.fj@fjmu.edu.cnPurpose: The study was intended to compare the surface properties and the bacterial and biofilm adhesion resistance of two potential antibacterial nanometer titanium dioxide (nano-TiO2) coatings on dental titanium (Ti) abutments prepared by atomic layer deposition (ALD) and the anodic oxidation (AO) techniques.Methods: Nano-TiO₂ coatings were developed using ALD and AO techniques and applied to Ti surfaces. The surface properties and the bacterial and biofilm adhesion resistance of these coatings were evaluated against commonly used Ti and Zirconia (ZrO₂) surfaces. The chemical compositions, crystalline forms, surface topography, roughness and hydrophilicity were characterized. The antibacterial performance was assessed by the scanning electron microscope (SEM), the Colony-forming unit (CFU) assay and the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay using in vitro models of Staphylococcus aureus (S. aureus), Streptococcus mutans (S. mutans), and Porphyromonas gingivalis (P. gingivalis) in both single- and mixed-species bacterial compositions.Results: ALD-prepared nano-TiO₂ coatings resulted in a dense, smooth, and less hydrophilic surface with an anatase phase, significantly reducing the adhesion of the three bacteria by over 50%, comparable to ZrO₂. In contrast, AO-prepared coatings led to a less hydrophilic surface, characterized by various nano-sized pores within the oxide film. This alteration, however, had no impact on the adhesion of the three bacteria. The adhesion patterns for mixed-species bacteria were generally consistent with single-species results.Conclusion: ALD-prepared nano-TiO₂ coatings on Ti abutments demonstrated promising antibacterial properties comparable to ZrO₂ surfaces, suggesting potential in preventing peri-implantitis. However, the bacterial and biofilm adhesion resistance of AO-produced nano-TiO₂ coatings was limited. Keywords: atomic layer deposition, anodic oxidation, titanium dioxide, dental abutment, surface properties, antibacterial effect

A novel facile approach to N-arylpyridoindazolium salts is proposed, based on direct oxidation of the ortho-pyridine substituted diarylamines, either using bis(trifluoroacetoxy)iodobenzene as an oxidant, or electrochemically, via potentiostatic oxidation. Electrochemical synthesis occurs under mild conditions; no chemical reagents are required except electric current. Both approaches can be considered as a late-stage functionalization; easily available ortho-pyridyl-substituted diarylamines are used as the precursors.

The advancement in electrochemical techniques has unlocked a new path for achieving unprecedented oxidations and reductions of aryl radical precursors in a controlled and selective manner. This approach facilitates the construction of aromatic carbon−carbon and carbon−heteroatom bonds. In light of the green merits and the growing importance of this technique in aryl radical chemistry, this review aims to provide an overview of the recent advance in the electrochemical generation of aryl radicals organized by the aryl radical precursor type, with a focus on the substrate scope, limitation, and underlying mechanism, thereby inspiring future work on electrochemical aryl radical generation. [ABSTRACT FROM AUTHOR]

Titanium has been widely used in orthopedics and dental implants due to its excellent biocompatibility and mechanical properties. However, the surface of titanium is biologically inert and lacks biological activity, resulting in poor integration between titanium-based implants and surrounding natural bone tissue, which is a common challenge in its clinical application. Surface modification is currently an effective means to improve the biocompatibility and bioactivity of titanium implants. The natural tissues of the human body are assembled from nanomodules, so from a biomimetic perspective, nanostructures should have better biological activity. TiO2 nanotubes have unique physical and chemical properties due to their elastic modulus, large specific surface area, and regular hollow structure similar to those of bone tissue. This study used anodic oxidation technology to prepare TiO2 nanotubes on the surface of titanium. The surface properties of the nanotubes were evaluated using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), atomic force microscopy profilometry, contact angle measurements, etc. The corrosion resistance was tested using an electrochemical workstation. The results indicate that anodic oxidation can be used to successfully prepare titanium dioxide nanotube arrays on the surface of titanium. The nanotubes not only exhibit a good structure but also improve the surface hydrophilicity and corrosion resistance of titanium, thereby demonstrating potential for clinical application. [ABSTRACT FROM AUTHOR]

Molecular dynamic simulation along with experiments was used to study polycarbonate (PC) molecular conformation on composite interfacial properties. The interlaminar shear strength (ILSS) variations of composites with carbon fiber roughness were quite different between sized and unsized carbon fibers, which seem to conflict with the theory that rougher surface is harder to wet. By the results of molecular dynamic simulation, it was found that the conformation of PC molecules through solvent intervention could be higher, which is conducive to the formation of π–π stacking conformation between PC and carbon fibers and benefits the interface interaction, resultantly affecting the ILSS more when the carbon fiber surface area was low. When the specific surface area was high enough, the ILSS gets to a saturation value, because the fracture area changes from the interface to the matrix. It is concluded that the effects of sizing on ILSS varied with carbon fiber surface roughness, and the molecular conformation of the matrix affected by sizing or processing must be considered. Therefore, it is important to enhance the physical interactions with carbon fiber for thermoplastic resin matrixes. [ABSTRACT FROM AUTHOR]

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

Thin passive films on tungsten play an important role during the surface levelling of the metal for various applications and during the initial stages of electrochemical synthesis of thick, nanoporous layers that perform well as photo-absorbers and photo-catalysts for light-assisted water splitting. In the present work, the passivation of tungsten featuring metal dissolution and thin oxide film formation is studied by a combination of in situ electrochemical (voltammetry and impedance spectroscopy) and spectro-electrochemical methods coupled with ex situ surface oxide characterization by XPS. Voltametric and impedance data are successfully reproduced by a kinetic model featuring oxide growth and dissolution coupled with the recombination of point defects, as well as a multistep tungsten dissolution reaction at the oxide/electrolyte interface. The model is in good agreement with the spectro-electrochemical data on soluble oxidation products and the surface chemical composition of the passive oxide. [ABSTRACT FROM AUTHOR]

We report an electrochemically promoted decarboxylation of readily available carboxylic acid and subsequent Mumm rearrangement to synthesize the corresponding imides. The reaction features external oxidant‐free, transition metal‐free mild conditions, and good functional group tolerance, affording various imides in moderate to good yields. Mechanistic studies reveal that the selective oxidation of aliphatic carboxylic acids appears to be the key step in this transformation. [ABSTRACT FROM AUTHOR]

In this study, the purification of caffeine by electrochemical oxidation, one of the advanced oxidation processes, was systematically investigated. A boron-doped diamond electrode was used as the anode, which has a high potential for the production of large amounts of hydroxyl radicals. The effects of applied current density, initial pH, supporting electrolyte concentration, cathode type, anode-cathode distance, and initial caffeine concentration were evaluated. The results showed that the electrochemical degradation rates of caffeine follow pseudo-first-order kinetics, with rate constants ranging from 0.0154 to 0.0496 min-1 depending on the operating parameters. The applied current density and the electrolysis time proved to be the most important parameters influencing both caffeine degradation and energy consumption. However, varying the initial caffeine concentration and the concentration of the supporting electrolyte also influenced the caffeine degradation rates. Changing the anode-cathode distance and the type of cathode has no effect on the rate of caffeine degradation, but it does have an effect on energy consumption. A current density of 20 mA cm-2, a supporting electrolyte concentration of 50 mM K2SO4, an anode-cathode distance of 2 mm, a cathode type of stainless steel, and an initial solution pH of 3 were found to be optimal values for the degradation of a solution containing 25 mg L-1 caffeine in 45 minutes using a boron-doped diamond anode. Finally, it was found that the pH value of the solution tended to increase during electrolysis. [ABSTRACT FROM AUTHOR]

The degradation of industrial dyes poses a significant environmental challenge due to their persistence and toxicity. Developing efficient and stable electrode materials for the electrochemical degradation of methylene blue (MB) is crucial for addressing environmental concerns associated with dye pollution. This paper describes the synthesis and electrochemical performance of Cu(Cr0.1,Al0.9)2O4 as a potential electrode material for the degradation of MB. The material was elaborated via nitrate synthesis and heat-treated at 900 °C. Then, characterized using various physico-chemical techniques. For all the electrochemicals tests, an anode based on Cu(Cr0.1,Al0.9)2O4 was prepared by adding activated carbon (AC), NMP and PVDF as binder agents. Preliminary electrochemical tests indicated that the degradation of MB occurred via an indirect oxidation mechanism, which needs the integration of a supporting electrolyte. In this case, the electrolyte consists of mixture of Na2SO4 and NaCl at equal proportions (in volume). The pH study showed that the degradation efficiency was found vary between 92.4% and 97.2% at pH range 2–11. The electrode also exhibited excellent performance irrespective the dye concentrations, with efficiencies ranging from 91 to 99% for solutions at 6.4 to 40 ppm of MB. The prepared electrode revealed a maximum degradation efficiency of 99% (within 50 min) at 50 mA applied current, for a 20 ppm MB solution. A higher current is required to decontaminate a concentrated solution. On the other hand, increasing the current reduces the electrolysis time. For a 40 ppm solution, the degradation efficiency reached 97.4% at an applied current of 70 mA within only 40 min. [ABSTRACT FROM AUTHOR]

The current comprehensive review covers four main parts, of which some are presented in the form of a personal account. 1. Anodic oxidation of a) N‐alkyl and N,N‐diallyl carbonyl moieties, b) Azacycloalkyl amides and the effect of ring‐size on the outcome, c) Lactams, d) Sulfonamides, and e) The effect of a substituent R attached to carbonyl (N−CO−R) or sulfonamides (N−SO2R) on their oxidation potentials. 2. Anodic oxidation of aromatic amides, in particular of type Ph2CHCONHAr, lacking hydrogen(s) at the α‐position to nitrogen. They undergo three types of bond‐cleavage, yielding a variety of fragmentation products. 3. a) Anodic oxidation of symmetrical bisamides of type ZCONH(CH2)nNHCOZ (Z=Me, Ph, Ar; n=2–4) under constant current electrolysis, in methanol. For n=3, 4 they afford mostly mono‐ and dimethoxylation products. For n=2 they undergo ′CH2−CH2′ bond cleavage to yield fragmentation products. b) Anodic oxidation of symmetrical bisamides of type ArCONH(CH2)2NHCOAr under controlled potential electrolysis, in acetonitrile, leads to gem‐unsymmetrical bisamides of type ArCONHCH2NHCOMe as the major product, in fair yields. 4. Utilization of the anodic process in organic synthesis to form C−C bonds by both intra‐ and inetrmolecular processes; as well as C−O and C−N bonds for generating heterocycles. [ABSTRACT FROM AUTHOR]

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

The principle of Fenton reagent is to produce ·OH by mixing H2O2 and Fe2+ to realize the oxidation of organic pollutants, although Fenton reagent has the advantages of non-toxicity and short reaction time, but there are its related defects. The Fenton-like technology has been widely studied because of its various forms and better results than the traditional Fenton technology in terms of pollutant degradation efficiency. This paper reviews the electro-Fenton technology among the Fenton-like technologies and provides an overview of the homogeneous electro-Fenton. It also focuses on summarizing the effects of factors such as H2O2, reactant concentration, reactor volume and electrode quality, reaction time and voltage (potential) on the efficiency of electro-Fenton process. It is shown that appropriate enhancement of H2O2 concentration, voltage (potential) and reaction volume can help to improve the process efficiency; the process efficiency also can be improved by increasing the reaction time and electrode quality. Feeding modes of H2O2 have different effects on process efficiency. Finally, a considerable number of experimental studies have shown that the combination of electro-Fenton with ultrasound, anodic oxidation and electrocoagulation technologies is superior to the single electro-Fenton process in terms of pollutant degradation. [ABSTRACT FROM AUTHOR]

In this study, a superhydrophobic surface was successfully prepared on Al alloy 5052 using a simple anodic oxidation method followed by fluorination treatment. This study demonstrates the construction of rough structure of Al oxide by an anodic oxidation reaction, which improves the superhydrophobicity of the alloy. The top, tilt, and cross‐views of the samples were characterized by field‐emission scanning electron microscopy and focused ion beam. The chemical composition of the samples was analyzed by energy‐dispersive X‐ray spectroscopy and Fourier‐transform infrared spectroscopy. The structure of the surface was effectively modified as the anodization time increased. The optimum anodic oxidation reaction was carried out for 4 min in a 0.2‐M H3PO4 aqueous electrolyte at 50°C under a constant voltage of 120 V to create a pore‐and‐dendrite hybrid nanostructure. The water contact angle values were maximized in the hybrid nanostructure because their solid fraction area was smaller than that in the porous structure. Corrosion measurements proved that the superhydrophobic surface can significantly inhibit the corrosion of the substrate alloy with an inhibition efficiency of 99.99%. In addition, the prepared superhydrophobic sample exhibited good self‐cleaning properties. [ABSTRACT FROM AUTHOR]

The inert surface of high-modulus carbon fiber leads to the weak interface between it and the resin matrix， which limits the performance of high-modulus carbon fiber composite in many application scenarios. Anodic oxidation is the only surface treatment technology that can be combined with carbon fiber production lines until now，but the commonly used alkaline electrolytes represented by ammonium bicarbonate exhibit limited effect on the oxidation of high-modulus carbon fiber. The acidic electrolyte system has stronger oxidation ability， lacks systematic researches on anodizing mechanism . In this paper， dilute sulfuric acid was used for the anodic oxidation for carbon fiber with a modulus of 371 GPa. The effects of key factors such as current density， electrolyte concentration on the polar structure of the surface of high-modulus carbon fiber were systematically studied， and then the effects of surface treatment on the interfacial shear strength of carbon fiber/epoxy resin composites were investigated. The correlation between surface treatment factors and interfacial properties of composites was established. The results show that after the treatment， the surface morphology and graphitized structure of the carbon fiber are maintained， and oxidation reactions occur in the amorphous carbon and aromatic ring structure regions of the carbon fiber. After the reaction， the graphitization degree of the fiber decreases apparently， the surface energy increases， and the content of surface oxygen-containing functional groups increases. When sulfuric acid concentration is 1.0%（mass fraction） and current density is 0.26 mA/cm2， the surface energy of carbon fiber is the highest （57.7 mN/m）， which is 62.08% higher than that of untreated carbon fiber. The interfacial shear strength between carbon fiber and epoxy resin reaches 80.9 MPa， which is 2.7 times higher than that of untreated one corresponding to 21.8 MPa.Furthermore， the single fiber tensile strength of the treated carbon fiber exhibits undamaged.

Ti–Mo–Zr alloys have attracted increasing interest for biomedical applications, due to their outstanding properties such as low elastic modulus. To improve the bioactivity of alloys, this study utilized the anodic oxidation method to fabricate porous micro/nano structures on the surface of a series of Ti–Mo–Zr alloys, including the Ti–12Mo-AO, Ti–10Zr-AO, and Ti–12Mo–10Zr-AO groups. The morphology, composition, phase, microhardness, roughness, wettability, adhesion strength, corrosion resistance, bioactivity, and biocompatibility of each group were systematically investigated. The formation mechanism of surfaces was discussed from the perspective of thermodynamics. Our results demonstrated that, Ti–12Mo-AO showed the structure of single-layer regularly arranged nanotubes, while Ti–10Zr-AO and Ti–12Mo–10Zr-AO exhibited a double-layer porous structure with a nano-filamentous upper layer and a densely arranged nanotube lower layer. With low crystallinity, these surfaces showed an amorphous structure and were composed of the oxides of corresponding matrix element. After anodizing, the microhardness and wettability of surfaces increased, while their corrosion resistance decreased. Compared with Ti–12Mo-AO, Ti–10Zr-AO and Ti–12Mo–10Zr-AO possessed a higher degree of roughness, better wettability, stronger interface bonding, and higher apatite forming ability. Furthermore, the biocompatibility of Ti–12Mo–10Zr-AO was superior to that of the other groups. Taken together, our results revealed that, under the same anodic oxidation condition, Ti–Mo–Zr alloys formed different porous micro/nano structures on the surface. Particularly, due to its favorable properties, Ti–12Mo–10Zr-AO is very attractive for future biomedical application.

Abstract: This review provides a current opinion on the most recent works that have been published toward the application of electrochemical advance oxidation processes (EAOPs) for the degradation of pharmaceutical and personal care products (PPCPs) in water streams. Advances in the application of anodic oxidation (AO)- and electro-Fenton (EF)-based processes are reported, including operational conditions, electrode performance, and removal. Although AO- and EF-based processes can easily reach 100% removal of PPCPs, mineralization is desirable to avoid the generation of potential toxic byproducts. The following section exploring some techno-economic aspects of the application of EAOPs is based on electrode selection, operational costs as well as their use as cotreatments, and their synergistic effects. Finally, this short review ends with perspectives about the emerging topics that are faced by these technologies applied for the degradation of PPCPs in research and practice.

The research into affordable and highly efficient overall water splitting electrocatalytic electrodes represents a crucial strategy for decentralised power generation. This study employed a two-step electrochemical method consisting of dealloying and anodic oxidation to construct microwave sintered AlCoCrFeNi high entropy alloy self-supporting efficient overall water splitting electrode. The AlCoCrFeNi high entropy alloy is mainly composed of BCC and FCC phases. After electrochemical treatment, a porous structure is formed on the surface of the AlCoCrFeNi high entropy alloy with in situ growth of ice-crystalline and lamellar structures predominantly composed of M-OOH. These structures enhance the surface wettability of the electrode and accelerate the bubble desorption during the water splitting process. After electrochemical dealloying and anodic oxidation, the overpotential of AlCoCrFeNi electrode for OER (HER) at 100 mA cm−2 significantly decreases from 366 (238) mV to 279 (173) mV, and the Tafel slope is considerably reduced to 39.73 (97) mV dec−1. Ultimately only a potential of 1.74 V is required to achieve overall water splitting at 100 mA cm−2. Excellent electrocatalytic performance of the electrode is attributed to abundant porous structure and the abundance of active sites provided by the M-OOH. Both of chronopotentiometry and continuous CV results show that the electrode has excellent electrocatalytic stability of OER, HER, and overall water splitting. This suggests that structural adjustments and surface modifications of bulk electrodes through multistep electrochemical treatment offer a new avenue for the development of overall water splitting electrodes. [Display omitted] • A self-supporting overall water splitting electrode was prepared by microwave sintering. • The HEA electrode was treated by a two-step electrochemical method. • The more abundant porous structures was obtained by electrochemical dealloying. • The ice-crystalline and lamellar structures were formed by anodic oxidation. • A potential of 1.74 V was required to achieve overall water splitting at 100 mA cm−2. [ABSTRACT FROM AUTHOR]

The mixed wastewater generated by anodic oxidation coating facilities contains high levels of various contaminants, including iron, aluminum, conductivity, chemical oxygen demand (COD), and sulfate. In this study, the effectiveness of the membrane distillation (MD) process using polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) membranes was investigated to treat mixed wastewater from an anodized coating factory. The results indicate that both hydrophobic membranes effectively removed targeted contaminants. However, the PTFE membrane achieved higher removal efficiencies, with over 99% removal of sulfate, conductivity, iron, and aluminum, 85.7% of COD, and 86% of total organic carbon (TOC). In contrast, the PVDF membrane exhibited a significant decline in removal efficiency as the temperature increased and performed well only at lower feed temperatures. The PTFE membranes outperformed the PVDF membranes in treating chemically intensive anodic oxidation wastewaters. This superiority can be attributed to the PTFE membrane's morphology and structure, which are less influenced by feed water temperature and chemicals. Additionally, its slippery surface imparts anti-adhesion properties, effectively preventing membrane fouling, and maintaining the treated water quality and flux for longer operation time. [ABSTRACT FROM AUTHOR]

Dairy wastewater (DW) contains a high concentration of organic and inorganic pollutants. In recent years, extensive research has been conducted to develop more efficient techniques for the treatment of DW. Electrochemical advanced oxidation processes (EAOPs) have gained significant attention among the various treatment approaches. EAOPs rely on electrochemical generation of hydroxyl radicals (•OH) which are considered highly potent oxidizing compounds for the degradation of pollutants in DW. In this paper, we provide an overview of the treatment of DW using various EAOPs, including anodic oxidation (AO), electro-Fenton (EF), photo electro-Fenton (PEF), and solar photo electro-Fenton (SPEF) processes, both individually and in combination with other techniques. Additionally, we discuss the reactor design and operating parameters employed in EAOPs. The variation in degradation efficiency is due to different oxidizing agents produced in specific approaches and their pollutant degradation abilities. In AO process, •OH radicals generated on electrode surfaces are influenced by electrode material and current density, while EF procedures use Fe2+ to create oxidizing agents both on electrodes and in the DW solution, with degradation mechanisms being affected by Fe2+, pH, and current density; additionally, PEF and SPEF approaches enhance oxidizing component production and pollutant degradation using ultraviolet (UV) light. Integration of EAOPs with other biological processes can enhance the pollutant removal efficiency of the treatment system. There is a scope of further research to exhibit the effectiveness of EAOPs for DW treatment in large scale implementation. [ABSTRACT FROM AUTHOR]

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

Diamond films with different grain sizes are deposited on TiO2 nanotube (TNT) arrays prepared by anodic oxidation using a microwave plasma chemical vapor deposition reactor. The scanning electron microscope, X‐Ray diffractometer, and Raman results indicate that the diamond film is successfully deposited and that the substrate undergoes a phase transition due to the diamond deposition temperature, resulting in the rutile phase becoming dominant with lower energy bandgap and work function. Notably, after 5 h of deposition, a relatively continuous microcrystalline film is formed on the TNTs, and the diamond grains change from spherical to pyramidal and show excellent electron field emission behavior, with a low turn‐on field of 0.5 V μm−1 and a current density of 85.9 μA cm−2. In addition, the deposition environment of the nanocrystalline diamond has a large impact on the substrate morphology, resulting in a blocked electron transport path, which reduces the overall field emission performance. The enhanced performance is attributed to the synergistic effect between the highly efficient 1D electron path of the TNTs, the negative electron affinity of the diamond surface, and the lower work function of rutile TiO2. [ABSTRACT FROM AUTHOR]

Mg-rare earth (RE) alloy, i.e., Mg-1Zn-1Gd (ZG11), was treated by a conventional pulse anodization process. The effect of electrical parameters (processing time, duty cycle and applied current) on the microstructure and corrosion resistance of anodized film was investigated by orthogonal method. SEM and XRD were used to characterize the microstructures and compositions of anodized films. Polarization curve, electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM) were performed to evaluate the corrosion resistances of anodized samples. The results show that with the employment of appropriate electrical parameters, corrosion resistance of ZG11 alloy can be significantly enhanced (icorr decreases by nearly three orders of magnitude) after anodized for less than 2 min. Besides, the optimal sample selected from orthogonal experiments in terms of the thickness and porosity of anodized film appropriately matches with the sample with the best corrosion resistance determined by electrochemical corrosion measurements, indicating the strong relationship between the thickness and porosity of anodized film and its corrosion resistance. Additionally, results of cell proliferation tests demonstrate that the varied surface morphologies and microstructure characteristics of the anodized samples in the present study do not necessarily influence the related cytocompatibilities. The study helps to further understand the effect orders of different current parameters on the structure and properties of anodized film and therefore provides a high-efficiency and low-energy consumption way to manufacture Mg alloys with excellent corrosion resistances. [ABSTRACT FROM AUTHOR]

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

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Human activities in daily life and industrial production generate a significant volume of substandard water with high salt content, organic compounds, and other pollutants, often exhibiting a neutral pH. Electrochemical oxidation is a widely applied technique for the purification of water sources. By integrating electrochemical oxidation reactions with electrolytic hydrogen evolution reactions, the potential arises to enhance energy utilization efficiency and reduce cost implications. This study describes the advantages and challenges of neutral aqueous chlorine solutions as electrolytes for hydrogen production from electrolyzed water. The cathodic and possibly anodic reactions in the electrolysis of neutral chlorinated electrolytes are also investigated. Finally, we present the progress of research on cathode and anode catalysts used in electrolyzing neutral chlorine-containing electrolytes. The aim is to inspire the research of industrialized low-cost and high-yield integrated hydrogen production systems. [Display omitted] • Concluded the challenges of electrolysis of neutral chlorine-containing solutions. • Low-energy anode reaction coupled with hydrogen evolution reaction can reduce lower. • Concludes the design principles of cathode and anode catalysts for water splitting. [ABSTRACT FROM AUTHOR]

The electrochemical behavior of the biologically active redox chemicals is essential in point of view antibacterial activity. In some cases, the electronic exchanges are coupled to chemical reactions that produce new oxidative or reductive species, which might form electrodeposits. This contribution presents a comparative study of the antibacterial activities and the anodic oxidation of S-triazino-benzimidazole derivatives substituted at the triazine ring with phenyl, 4-fluorophenyl and pentafluorophenyl groups. By combining bactericidal screening against E. coli, P. aeruginosa, S. aureus, and S. typhimurium, to a cyclic voltammetry investigation, it was revealed that the fluorine phenyl substituents in the S-triazine benzimidazole derivatives enhance the electrons ejection to the platinum disk and the subsequent chemical reactions. Additionally, by cycling of potential the non-fluorinated chemical produces a rather passive film on the electrode surface, whereas the fluorinated ones generate electroactive and electrocatalytic coatings. Comparing the results obtained with S-triazino-benzimidazole derivatives to those with 2-aminobenzimidazole, plausible mechanisms of their bactericidal action are suggested. [ABSTRACT FROM AUTHOR]

Photocatalysis has attracted attention as a method for purifying pollutants, but how to simply and efficiently prepare catalyst films with high surface areas is still a challenge. Herein, a chrysanthemum‐like CuO–TiO2–Ag photocatalyst is prepared by anodic oxidation and magnetron sputtering. Scanning electron microscopy and energy dispersive spectrometry analyses show that Ag nanoparticles are uniformly modified on the surface of chrysanthemum‐like CuO–TiO2. Moreover, the influences of the thickness of the TiO2 film and the content of Ag nanoparticles on the degradation of rhodamine B (RhB) are studied by controlling the sputtering time. Among the prepared nanocomposites, the chrysanthemum‐like CuO–TiO2‐2.5‐Ag‐2 proves to have the maximal degradation level with regard to RhB by removing 91.16% RhB after 120 min under UV light. This is because the large surface area offers more active sites. In addition, the trapping experiments show that when CuO–TiO2 is decorated by Ag nanoparticles, this contributes to the movement of a number of photogenerated electrons from the conduction band of TiO2 to Ag, thereby improving the efficiency of charge transfer. The findings reveal that the photodegradation efficiency of the prepared nanocomposites in this study is greatly related to the thickness of the TiO2 film and the content of Ag nanoparticles. [ABSTRACT FROM AUTHOR]

The electrochemical behavior of a flat gold electrode in an acetonitrile solution of 3-(1,4-dimethyl-2,3,5,6-tetraoxabicyclo[2.2.1]hept-7-yl)propanoic acid was studied by cyclic voltammetry. The formation of colloidal gold particles was detected during the anodic oxidation. The kinetics of their formation was studied by the gravimetric method. Peroxide bonds in the cyclic peroxide molecule were found to be reduced on the cathode surface with the subsequent formation of the diketone fragment. [ABSTRACT FROM AUTHOR]

For the application of titanium and titanium alloys in orthopedic implant materials, the antibacterial properties and cell biocompatibility determine whether the implant surgery is successful. In this study, a functional anodic oxidation (AO) coating was successfully prepared to modify the surface of Ti-Ag alloy. The surface characteristics of the anodized Ti-Ag alloy were analyzed using techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and contact angle measurements. The corrosion characteristics of Ti-Ag samples were tested by an electrochemical workstation. In addition, the antibacterial properties and cell activity were studied by the plate count method and MC3T3-E1 cell staining. The results indicate that the AO process can generate a multi-functional TiO2/Ag2O coating with a large number of block and flower-like structures on the surface of a Ti-Ag alloy. When the AO voltage of the sample is 120 V, the maximum roughness is 0.73 μm and the minimum wetting degree is 23°, which improves the biocompatibility. The corrosion test results show that AO treatment can improve the corrosion resistance of a Ti-Ag alloy. The oxidation voltage is 20 V and the coating has the best corrosion resistance. The corrosion open circuit potential (Eocp) is 107.621 mV and the corrosion current density (icorr) is 2.241 × 10−8 A·cm−2. This coating can promote ion release and show more than 99% of a strong antibacterial ability against S. aureus. The results of the compatibility evaluation by cultured cells showed that the multifunctional coating formed by the anodic oxidation process did not cause cytotoxicity and promoted the adhesion of MC3T3-E1 cells. [ABSTRACT FROM AUTHOR]

Abstract The current comprehensive review covers four main parts, of which some are presented in the form of a personal account. 1. Anodic oxidation of a) N‐alkyl and N,N‐diallyl carbonyl moieties, b) Azacycloalkyl amides and the effect of ring‐size on the outcome, c) Lactams, d) Sulfonamides, and e) The effect of a substituent R attached to carbonyl (N−CO−R) or sulfonamides (N−SO2R) on their oxidation potentials. 2. Anodic oxidation of aromatic amides, in particular of type Ph2CHCONHAr, lacking hydrogen(s) at the α‐position to nitrogen. They undergo three types of bond‐cleavage, yielding a variety of fragmentation products. 3. a) Anodic oxidation of symmetrical bisamides of type ZCONH(CH2)nNHCOZ (Z=Me, Ph, Ar; n=2–4) under constant current electrolysis, in methanol. For n=3, 4 they afford mostly mono‐ and dimethoxylation products. For n=2 they undergo ′CH2−CH2′ bond cleavage to yield fragmentation products. b) Anodic oxidation of symmetrical bisamides of type ArCONH(CH2)2NHCOAr under controlled potential electrolysis, in acetonitrile, leads to gem‐unsymmetrical bisamides of type ArCONHCH2NHCOMe as the major product, in fair yields. 4. Utilization of the anodic process in organic synthesis to form C−C bonds by both intra‐ and inetrmolecular processes; as well as C−O and C−N bonds for generating heterocycles.

Potassium ferrate(VI) (K2FeO4) as a particularly strong oxidant represents an effective and environmentally friendly waste water treatment material. When produced by anodic oxidation in highly alkaline aqueous solution, the K2FeO4 product is separated and sealed in inert plastic bags with the retention of some liquid phase with high pH. This method proved to be excellent for long-term storage at moderately low temperature (5 °C) for industrial applications. It is still imperative to check the ferrate(VI) content of the product whenever it is to be used. Fe-57 Mössbauer spectroscopy is an excellent tool for checking the ratio of ferrate(VI) to the degradation product iron(III) in a sample. For this purpose, normally the spectral areas of the corresponding subspectra are considered; however, this approximation neglects the possible differences in the corresponding Mössbauer–Lamb factors. In this work, we have successfully determined the Mössbauer–Lamb factors for the ferrate(VI) and for the most common iron(III) degradation products observed. We have found superparamagnetic behavior and low-temperature phase transformation for another iron(III) degradation product that made the determination of the Mössbauer–Lamb factors impossible in that case. The identities of a total of three different iron(III) degradation products have been confirmed.

The recent advances in the area of electrophotocatalysis (EPC) show that it is a highly suitable technique to yield greener and more sustainable organic synthesis. The overall productivity of EPC however is constrained by a multitude of practical limitations, which impose difficulties in effectively harmonizing the photochemical and electrochemical steps, let alone in accelerating both steps simultaneously. In this contribution, we have tackled these limitations by developing a parallel plate flow cell that permits the execution of EPC in continuous flow. By using a transparent electrode, such as fluorine-doped tin oxide (FTO) or indium tin oxide (ITO) coated glass, the interelectrode distance could be reduced while improving photon absorption. By enhancing both the photochemical and electrochemical steps simultaneously, a notable increase in productivity and space–time-yield (a ten-fold and 300-fold improvement, respectively) of the N-arylation of different azoles was observed. In addition, this was achieved in a single-pass process under electrolyte-free conditions. Highlights: • We have created a flow cell that incorporates a transparent electrode, allowing simultaneous photochemical and electrochemical activation. • By using a parallel energy input, a productivity increase for the N-arylation of different azoles under electrolyte-free conditions was observed. • A single pass sufficed to reach high conversions, rendering this a true continuous flow process. [ABSTRACT FROM AUTHOR]

The electrocatalytic activity of electrode materials synthesized by anodic selective dissolution of Ag–Pd alloys based on silver (4 and 8 at % Pd) was studied. Kinetic regularities of formic acid electrooxidation on palladium and anodically modified Ag–Pd alloys in an acidic sulfate solution have been established. The process includes the diffusion of HCOOH, its dissociative chemisorption, and irreversible ionization of atomic hydrogen. The conditions for formic acid anodic oxidation on Pd and Ag–Pd alloys were determined depending on the composition of the electrode system and the mode of preliminary electrochemical modification (selective dissolution) of the alloy using transient electrochemical measurements. The role of the surface development of an alloy in the kinetics of anodic degradation of formic acid was revealed. It was shown that the selective dissolution of Ag–Pd alloys contributes to a noticeable increase in the rate of the kinetic stage of atomic hydrogen ionization. A necessary condition for the activation of the anodically modified alloy in relation to the electrooxidation of HCOOH is the excess of both critical parameters (charge and potential) corresponding to the onset of morphological development and phase transformations in the surface layer of the Ag–Pd systems. [ABSTRACT FROM AUTHOR]

[Display omitted] New ortho -substituted diarylamines prone to different types of the intramolecular H-bonding (IMHB) were obtained. In-depth NMR, IR and voltammetry study allowed selecting the amine that demonstrates stable reversible switching of the IMHB bond under the external stimuli, which can be used for the logic gate construction. [ABSTRACT FROM AUTHOR]

Magnesium alloys, notably AZ31B, hold promise for lightweight structural applications in the aerospace, automotive, and biomedical sectors due to their excellent strength-to-weight ratios. The broad adoption of these alloys, however, is hindered by their inherent susceptibility to corrosion, reducing durability and functional integrity in corrosive environments. This study explores anodic oxidation as a viable surface treatment to improve the corrosion resistance of the AZ31B magnesium alloy. Focusing on the impact of oxidation voltage on the oxide film's structural and electrochemical properties, we aim to optimize these characteristics to enhance the alloy's utility and lifespan significantly. Through detailed analysis of surface and cross-sectional morphologies, film thickness, phase composition, and corrosion resistance, we identify an optimal oxidation voltage of 17.5 V that notably improves the oxide film's density and corrosion resistance. Through this research, we contribute to the ongoing efforts to overcome the corrosion vulnerability of magnesium alloys, thereby unlocking their full potential in contributing to more sustainable and efficient technological advancements. [ABSTRACT FROM AUTHOR]