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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]

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]

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.

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]

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]

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]

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.

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]

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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]

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.

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]

This study investigated the oxidation of wastewater generated during the production of glass fiber manufacturing material, which contains high organic carbon (18.32 g/L) and has a pH of 8.8, by chemical coagulation, electrocoagulation and electroadvanced oxidation techniques. It was determined that the total organic content (TOC) of wastewater was reduced by 53% using the chemical coagulation method. After electrocoagulation with Al/Al electrode pair for 300 minutes at 500 mA, 73% TOC removal was achieved at pH 8.8. While 50% TOC removal was completed in 2 h at 400 mA in electrocoagulation with Fe/Fe electrode pair, 71% TOC removal was obtained in the combined electrocoagulation/electro-Fenton process by adding hydrogen peroxide to the medium under the same conditions. In addition, it was also observed that the success of the anodic oxidation methods alone was lower. The electro-Fenton application after electrocoagulation was effective and provided 78% TOC but required work at pH 3 and a longer treatment time. [ABSTRACT FROM AUTHOR]

In the present work, the feasibility of removing chemical oxygen demand (COD) from petroleum refiner wastewater (PRW) was examined through an anodic oxidation process using a SnO2-copper substrate anode in a prototype tubular batch electrochemical reactor. The SnO2 anode was prepared by cathodic deposition from a nitrate solution and characterized by techniques such as X-ray diffraction (XRD) and scanning electron microscopy (SEM). Effects of current density, [Sn2+]/[HNO3] molar ratio, and time on the properties of the prepared anode were investigated. The XRD results showed that main peaks corresponded to deposition of tetragonal SnO2. Besides, broad peeks were observed indicating that the deposits have a lower degree of crystallinity. The results confirmed that increasing current density higher than 10 mA/cm2 results in formation of a mixture of SnO2 and Sn deposits. Additionally, the results proved that [Sn2+]/[HNO3] molar ratio has the main effect on the electrodeposition process, where keeping this ratio lower than 0.33 is recommended to ensure pure SnO2 film deposition. The best conditions for electrodeposition of SnO2 as a compact film on a copper substrate were a current density of 10 mA/cm2, [Sn2+] of 25 mM, [HNO3] of 125 mM to make a molar ratio of 0.2, and 30 min to confirm the formation of deposits without cracks and having an atomic percent (Sn/O) of 20.6/65. The application of the prepared anode for removing of COD from PRW confirmed a good performance with a removal efficiency of 79 % at current density of 12 mA/cm2, pH of 7.8, and operating time of 150 min in which an energy consumption of 9.93 kWh/kg COD was required. The degradation of COD using the SnO2 electrode was found to obey a pseudo first-order kinetic. The application of anodic oxidation using the new configuration of the SnO2 anode can be considered an eco-friendly process for treating wastewater, featuring easy scale-up to an industrial scale at high removal efficiency and lower cost.

Heterogeneous multiphase reactors with nano photocatalysts are characterized by their high mass transfer rate due to the efficient hydrodynamic specifications. In the present work, a slurry bubble photoreactor with an external circulation of SnO2 nanoparticles was successfully used to remove the chemical oxygen demand (COD) from petroleum refinery wastewater. The influence of main effective variables such as SnO2 dosage, pH, and time on the removal efficiency (RE%) of COD was investigated and optimized using a response surface methodology (RSM). Results showed that pH has the most substantial impact on RE% with a contribution of 41.16%, followed by the time with a contribution of 28.68%, and finally by the dosage of SnO2 with a contribution of 18.21%. The optimum results of the treatment process were 0.1g/L SnO2, pH = 3, and time = 99 min which given COD removal of 73.16% combined with an electrical energy consumption of 25.5 kWh/m3. Moreover, the results of the kinetics showed that the degradation of COD using UV/SnO2 follows a pseudo first order with a correlation coefficient of 0.989. The reusability results showed that a slight decrease in the activity of SnO2 was observed at the end of 5 cycles where RE% decreased from 73.16% (in the first cycle) to 68.1% (at the five cycle) confirming the good reusability of SnO2 catalyst during the treatment of petroleum refinery wastewater. Finally, the adopting of a slurry bubble photoreactor with SnO2 photocatalyst proved to be an efficient system to degrade COD at low cost of energy.

The high toxicity and bio-stability of organochlorine pesticides have made organophosphorus pesticides (OPPs) more preferred today. Diazinon is one of the most widely used insecticides in the group of OPPs, which has high stability in the environment and causes neurobehavioral side effects in case of long-term exposure to humans. The present study aims to fabricate the PbO2 electrocatalyst on a graphite sheet (G/PbO2) and use it as a non-active anode for diazinon degradation. The effect of independent variables such as solution pH, current applied to the electrodes, initial concentration of diazinon and reaction time on the removal efficiency of the pesticide was studied. SEM and XRD results showed that lead dioxide crystals in the β-PbO2 phase were formed as compact pyramidal clusters on the surface of the anode. At solution pH 8, diazinon removal efficiency was significantly improved. However, in mild operating conditions (solution pH = 5 and a current = 0.4 A), diazinon removal efficiency with initial concentrations of 20 and 100 mg/L after 90 min of reaction was 100% and 70%, respectively. After optimizing the independent variables effective in the diazinon removal, the mineralization pathway was proposed considering intermediates identified by LC-MS analysis. The results of the present study confirm that anodic oxidation with PbO2 electrocatalyst can be an effective method for the degradation and mineralization of diazinon pesticide.

In this work, the influence of supporting electrolytes (sodium sulfate and sodium chloride) on the electrochemical oxidation of the antihypertensive drug losartan (LOS) was studied under different operating conditions such as current density (4.1–12.5 mA cm−2), electrolyte concentration (0.05–0.5 M), initial pollutant concentration (250–1000 μg L−1) and solution pH. The role of cathodes on the removal of LOS has been investigated using five different cathodes with carbonaceous cathodes showing better LOS removal. The effect of matrix composition has been studied using simulated water spiked with various constituents and real water matrices such as bottled water (BW) and wastewater (WW). The removal of LOS was pronounced while using a chloride electrolyte as compared to the sulfate electrolyte. The apparent rate constant increased on adding persulfate (PS) up to concentrations of 150 mg L−1 and decreased in the presence of bicarbonates and organic matter. The transformation products (TPs) formed during the electrochemical oxidation depended on the supporting electrolyte and two common TPs were identified in both electrolytes with a total of 4 TPs identified in the chloride medium and 7 TPs in the sulfate medium. Degradation pathways for LOS in both electrolytes have also been proposed.

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.

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. HIGHLIGHTS EAOPs are an attractive alternative for PPCPs such as antibiotics and personal care products.; Anodic oxidation and electro-Fenton can fully mineralize PPCPs in water at short terms with some trade-offs.; Techno-economical aspects such as the lifetime of electrodes and operating costs are the main constrain for EAOPs application.; Cotreatments and synergistic processes could be considered for the successful application of EAOPs.;

In the context of rapid social development, it is urgent to address the increasingly prominent issues of fossil energy depletion and environmental pollution. As a result, research has focused on the creation of new clean energy sources such as solar, wind, biological, geothermal, and hydrogen. Hydrogen energy is one of these new energy sources that has drawn a lot of attention because of its low weight, good thermal conductivity, high heating value, rich utilization forms, and diverse storage states. Nowadays, one of the most significant methods for producing clean energy is photoelectrochemical (PEC) water splitting for hydrogen. However, the intrinsic drawbacks of commonly used semiconductors, such as the low light absorption efficiency, high carrier recombination rate, and slow oxygen evolution kinetics, have become the main barriers preventing their advancement in PEC water splitting. This study used anodic oxidation to create N-doped 4H-SiC nanowire arrays (NWAs) from N-doped 4H-SiC single crystalline wafers. It can be verified that the highly oriented N-doped 4H-SiC NWAs are fully exposed by removing the cap layer. Additionally, the single bamboo-shaped nanowire that was produced has a diameter of ~30–50 nm. Focusing on the optimization of the oxygen evolution reaction (OER) conditions, the NWAs were used as an integrated photoanode in a typical three-electrode system to achieve effective PEC water splitting for hydrogen production under illumination and electric field. Notably, the N-doped 4H-SiC NWAs show better water splitting performance compared with the bulk; that is, the onset potential is decreased from 1.224 V to −0.021 V versus the Ag/AgCl electrode, and the current density is increased from 2.64 mA∙cm−2 to 3.61 mA∙cm−2 at 1.4 V. Particularly, the N-doped 4H-SiC NWAs exhibit an extremely sensitive response to light. The improved optical absorption capacity and efficient charge transfer of N-doped 4H-SiC NWAs are responsible for the improvement in PEC water splitting performance. On the one hand, when the N-doped 4H-SiC NWAs are exposed to light, a significant amount of light shines into the gap between the nanowires. N-doped 4H-SiC obtains additional light absorption pathways with the constant reflection of the light, significantly enhancing the light absorption efficiency. On the other hand, the NWAs can considerably reduce the hole travel distance and avoid the recombination of the photogenerated electron-hole pairs, making more charges participate in the redox reaction to enhance the PEC water splitting performance of N-doped 4H-SiC. By building semiconductor photoanode nanostructures, it is possible to efficiently absorb light and transfer charge, significantly enhancing the PEC water splitting efficiency.

The lightweight of automobiles，high-speed trains and other transportation vehicles，as well as the implementation of China’s marine strategy，has expanded more application fields for aluminum alloys and put forward higher requirements for the performance of anodic oxide film on aluminum alloy.In this paper，the basic processes，properties，and applications of three single acid anodic oxidation systems of sulfuric acid，chromic acid and oxalic acid，as well as two mixed acid anodic oxidation systems of sulfuric acid-boric acid and sulfuric acid-organic acid were introduced.Combined with the application field of aluminum alloy，the actual demand for the preparation of anodic conversion film with high corrosion resistance，high toughness，high expansion coefficient，impact resistance was put forward.The fundamental way to improve the performance of the oxide film was to develop a new anodic oxidation system and form a composite conversion film through anodic oxidation and chemical conversion.Several feasible aluminum alloy composite oxide film preparation systems were proposed by the author team，and a composite oxide film mainly composed of alumina was prepared through experiments.The porosity of the film reached 60%，and there were basically no cracks after bending at 90 °，much better than that of ordinary sulfuric acid anodic oxide films，which presented the guiding significance for further research and development.

TiO2 nanotube (TNT) morphology is crucial for applications in a variety of fields. In this paper, response surface methodology (RSM) has been utilized to optimize the anodizing parameters i.e., electrolyte concentration (C), anodization voltage (V), and time (t) for morphology (e.g., nanotube diameter and length) of TNTs. Ethylene glycol (EG) based electrolyte has been used for anodization employing ammonium fluoride (NH4F) as a source of fluoride ion (F–) with 2.5 vol% H2O. Reliable regression models have been developed between the input variables and the corresponding responses, namely tube diameter and length with multiple regression coefficients of 0.9649 and 0.9253, respectively, revealing a trustworthy association between the actual and those predicted values using the quadratic model. The predicted values of C (0.31 wt%), V (38.44 V), and t (69.37 min) were found to be the optimum anodization condition preceding a TiO2 nanotubes diameter of 99.31 nm and length of 4572.64 nm. It was observed that the nanotubes diameter and length are more affected by anodizing voltage and time, and less sensitive to NH4F concentration. Therefore, RMS could be an appropriate technique to optimize anodizing parameters for producing TiO2 nanotubes with good morphology.

Based on the existing literature, active chlorine‐mediated electrochemical oxidation has been extensively studied when Cl‒ is added or Cl‒ is already present in the water matrices, as well as when Cl‒ is released from the target organic pollutants during their degradation. However, no attempts have been published concerning the fate and role of bromide (Br‒) ions released during the anodic oxidation (AO) of organobromine compounds. Therefore, the AO of bromophenol blue dye (BPB) was investigated in a parallel plate flow reactor using a boron‐doped diamond (BDD) anode. The effect of the applied current on the color removal efficiency and mineralization of BPB solution was examined and compared with AO of phenol red (PR) which has a similar molecular structure to BPB (but without Br) in order to understand the role of Br heteroatoms on the mineralization of BPB. Faster and higher mineralization and discoloration were achieved when treated with BPB solution compared to PR under similar experimental conditions. This behavior was associated with the electrogeneration of BrO‒, from the heteroatom Br which is released as the bromide ion (Br‒), during the degradation of BPB. The active bromine species are formed via direct and indirect oxidation approaches which were proposed based on ion chromatography and linear scanning voltammetry analysis. [ABSTRACT FROM AUTHOR]

The anodic reactivity of UO2 and UO2 doped with Gd2O3 was investigated by electrochemical methods in slightly alkaline conditions in the presence of silicate and calcium. At the end of the experiments, the electrodes were analysed by X-ray photoelectron spectroscopy to determine the oxidation state of the uranium on the surface. The experiments showed that the increase in gadolinia doping level led to a reduction in the reactivity of UO2, this effect being more marked at the highest doping level studied (10 wt.% Gd2O3). This behaviour could be attributed to the formation of dopant-vacancy clusters (GdIII-Ov), which could limit the accommodation of excess O2− into the UO2 lattice. In addition, the presence of Ca2+ and SiO32− decreased the anodic dissolution of UO2. In summary, the Gd2O3 doping in presence of silicate and calcium was found to strongly decrease the oxidative dissolution of UO2, which is a beneficial situation regarding the long-term management of spent nuclear fuel in a repository. [ABSTRACT FROM AUTHOR]

Tunisia has been compelled to use treated wastewater in irrigation due continuous increase in demand. Since 1999, the Edissa perimeter in Gabes, Tunisia, has been watered with treated wastewater (TWW) from the Gabes sewage treatment plant. However, it is imperative to assess the quality of this water source. The current study aims to accomplish tertiary treatment of TWW of Gabes sewage treatment plant using alternate processes by combining anodic oxidation processes using solar energy with coagulation--flocculation. Treatment under optimal conditions has shown that the combination of two processes was effective in achieving a reduction in pollution with satisfactory results in terms of elimination of the chemical oxygen demand (100%), total organic carbon (100%), biochemical oxygen demand (86%), Cl-, NH4+, NO3-, and PO43- with abatement rates of (100%). The concentration of heavy metals including (Ni, AI, Cu, Pb, Zn, Fe, Cr, Cd) have been reduced from 45% for Fe to 95% for Ni, and complete elimination of germs. [ABSTRACT FROM AUTHOR]

Isoxazol(in)es are widely featured structural motifs in natural products, agrochemicals, and pharmaceuticals. The first intermolecular approach for a direct electrochemical synthesis from readily available aldoximes is reported. Isoxazoles and isoxazolines were obtained in yields up to 81 %. The synthesis is carried out in an undivided cell as the simplest electrochemical set‐up and requires only the use of electric current as traceless oxidizing agent. The application of inexpensive and widely available electrode materials in combination with recyclable supporting electrolytes and solvents paves the path for translation of the presented reaction onto preparative scale. This is underlined by successful scale‐up to multi‐gram runs. [ABSTRACT FROM AUTHOR]

Tungsten oxide has received considerable attention as photo-anode in photo-assisted water splitting due to its considerable advantages such as significant light absorption in the visible region, good catalytic properties, and stability in acidic and oxidative conditions. The present paper is a first step in a detailed study of the mechanism of porous WO3 growth via anodic oxidation. In-situ electrochemical impedance spectroscopy (EIS) and intensity modulated photocurrent spectroscopy (IMPS) during oxidation of W illuminated with UV and visible light are employed to study the ionic and electronic processes in slightly acidic sulfate-fluoride electrolytes and a range of potentials 4–10 V. The respective responses are discussed in terms of the influence of fluoride addition on ionic and electronic process rates. A kinetic model is proposed and parameterized via regression of experimental data to the EIS and IMPS transfer functions. [ABSTRACT FROM AUTHOR]

The binary Zn-1wt.% X (X = Mg or Sr) alloys prepared by the application of mechanical alloying (MA) combined with powder metallurgy were modified by micro-arc oxidation (MAO) treatment in the 2 g/dm3 KOH aqueous solution at 200 V for 1 min for the formation of the ZnO layer. The Zn-alloys, obtained through the powder metallurgy method, are characterized by a dispersive microstructure that significantly improves its microhardness up to 90.5 HV0.3 for the Zn-1wt.%Mg sample after 24 h of MA. In the case of Zn-1Mg alloy after 24 h of mechanical alloying, Zn-1Mg alloy after 48 h of mechanical alloying, and Zn-1Sr alloy after 48 h of mechanical alloying, except for the main αZn phase, the traces of a second phase are noticed: MgZn2 and SrZn13. After the proposed MAO treatment, a zinc oxide (ZnO) layer on the zinc alloys was formed, allowing a significant improvement in the corrosion resistance and surface wetting properties. The potential of the modified ZnO layer is moved to more noble values in the case of MAO-treated samples α-Zn, Zn-1Mg (after 24 h of MA), and Zn-1Sr (after 48 h of MA). The obtained results show a good prospective potential of Zn-1wt.% X (X = Mg or Sr) binary alloys in the application of biodegradable materials. [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 Based on the existing literature, active chlorine‐mediated electrochemical oxidation has been extensively studied when Cl‒ is added or Cl‒ is already present in the water matrices, as well as when Cl‒ is released from the target organic pollutants during their degradation. However, no attempts have been published concerning the fate and role of bromide (Br‒) ions released during the anodic oxidation (AO) of organobromine compounds. Therefore, the AO of bromophenol blue dye (BPB) was investigated in a parallel plate flow reactor using a boron‐doped diamond (BDD) anode. The effect of the applied current on the color removal efficiency and mineralization of BPB solution was examined and compared with AO of phenol red (PR) which has a similar molecular structure to BPB (but without Br) in order to understand the role of Br heteroatoms on the mineralization of BPB. Faster and higher mineralization and discoloration were achieved when treated with BPB solution compared to PR under similar experimental conditions. This behavior was associated with the electrogeneration of BrO‒, from the heteroatom Br which is released as the bromide ion (Br‒), during the degradation of BPB. The active bromine species are formed via direct and indirect oxidation approaches which were proposed based on ion chromatography and linear scanning voltammetry analysis.

Electrodeposition of metal oxides on graphite electrodes can improve their ability to remove organic substances. In this work, multicomponent oxides of Mn, Co, and Ni were electrochemically deposited on both the anode and cathode of graphite electrodes to enhance their performance in removing phenol. Formation of the deposit was achieved within 2 h in current densities of 20, 25, 30, and 35 mA/cm2 for better composite properties. The deposited layer was characterized by testing the surface structure, morphology, composition, and roughness. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and Atomic force microscopy (AFM) techniques facilitated these tests. The composite electrodes have synthesized with a metal salts concentration, i.e., Co(NO3)2, Ni(NO3)2, and MnCl2 of 0.1 M with a mixing ratio of 1:1:1. The results exhibited a remarkable formation of the deposit on both the anode and cathode of our electrochemical cell. An amorphous skin of Mn–Co–Ni oxide was constituted on the anode, while a crystalline film of Mn–Co–Ni oxide accumulated on the cathode. The effectiveness of composite electrodes was examined at current densities of 40, 60, and 80 mA/cm2, pH values of 3, 4 and 5, and NaCl concentration of 1, 1.5, and 2 g/l with an electrolysis time of 1 h. The results show that the removal efficiency of phenol increases with the increase in current densities and NaCl concentration, while it decreases with increasing of alkalinity. The highest removal occurs at the pH, current density and NaCl concentration of 3, 80 mA/cm2, and 2 g/l. The highest obtained removal efficiency is 99.68% which reflects a tremendously high performance of our multicomponent composite for phenol removal and reducing electrolysis time compared to previous studies.

Abstract Isoxazol(in)es are widely featured structural motifs in natural products, agrochemicals, and pharmaceuticals. The first intermolecular approach for a direct electrochemical synthesis from readily available aldoximes is reported. Isoxazoles and isoxazolines were obtained in yields up to 81 %. The synthesis is carried out in an undivided cell as the simplest electrochemical set‐up and requires only the use of electric current as traceless oxidizing agent. The application of inexpensive and widely available electrode materials in combination with recyclable supporting electrolytes and solvents paves the path for translation of the presented reaction onto preparative scale. This is underlined by successful scale‐up to multi‐gram runs.

Using hexagonal boron nitride (h-BN) to prepare resistive switching devices is a promising strategy. Various doping methods have aroused great interest in the semiconductor field in recent years, but many researchers have overlooked the various repetitive anomalies that occur during the testing process. In this study, the basic electrical properties and additive protrusion behavior of Ga-ion-doped h-BN memristors at micro–nanoscale during the voltage scanning process are investigated via AFM and energy dispersive spectroscopy. The additive protrusion behavior is subjected to exploratory research, and it is concluded that it is caused by anodic oxidation. An approach is proposed that involves filling the AFM chamber with nitrogen gas to improve the stability of memristor testing, and this method provides a solution for enhanced testing stability of memristors. HIGHLIGHTS: • Gives insights into the electrical properties of Ga-ion-doped h-BN memristors at micro–nanoscale via AFM. • Investigates and solves the issue of protrusion behavior in electrical measurements of Ga-ion-doped h-BN. [ABSTRACT FROM AUTHOR]

Titanium alloy Ti6Al4V is a commonly used bone implant material, primarily prepared as a porous material to better match the elastic modulus of human bone. However, titanium alloy is biologically inert and does not have antibacterial properties. At the same time, the porous structure with a large specific surface area also increases the risk of infection, leading to surgical failure. In this paper, we prepared three porous samples with different porosities of 60%, 75%, and 85%, respectively (for short, 3D-60, 3D-75, and 3D-85) using 3D printing technology and clarified the mechanical properties. Through tensile experiments, when the porosity was 60%, the compressive modulus was within the elastic modulus of human bone. Anodic oxidation technology carried out the surface modification of a 3D-printed porous titanium alloy with 60% porosity. Through change, the different voltages and times on the TiO2 oxide layer on the 3D-printed porous titanium alloy are different, and it reveals the growth mechanism of the TiO2 oxide layer on a 3D-printed unique titanium alloy. The surface hydrophilic and antibacterial properties of 3D-printed porous titanium alloy were significantly improved after modification by anodic oxidation. [ABSTRACT FROM AUTHOR]

This work presents the electrochemical degradation of the herbicide Diuron by anodic oxidation on a Ti/Ru0.3Ti0.7O2 metal mixed oxide anode using sulfate as the electrolyte. The study includes the influence of Diuron concentration and current density on anodic oxidation. The results evidence a first-order degradation, with the highest capacity achieved at 40 mA cm−2 and at an initial Diuron concentration of 38 mg L−1. Nevertheless, in terms of efficiency and energy demand, the operation at 10 mA cm−2 is favored due to the more efficient and less energy-consuming condition. To discern the optimum design and operation conditions, this work presents the results of a preliminary technical–economic analysis, demonstrating that, to minimize the total costs of the system, it is recommended to seek the most efficient conditions, i.e., the conditions demanding the lowest applied charges with the highest Diuron degradation. At the same time, attention must be given to the required cell voltage to not increase excessively the operating costs. [ABSTRACT FROM AUTHOR]

A series of three-dimensional porous lead dioxide anode materials were prepared by anodizing method using oxygen bubbles as templates. The effects of additives sodium acetate, cetyltrimethyl ammonium bromide(CTAB), sodium dodecyl benzene sulfonate(SDBS) and polyethylene glycol(PEG) on three-dimensional porous PbO2 anode materials were studied. The morphology and phase composition of the electrode surface were characterized by SEM and XRD. The electrocatalytic activity of the electrode material in Na2SO4 solution was determined by anodic polarization curve(LSV), cyclic voltammetry curve(CV) and AC impedance spectrum(EIS).The results show that after the addition of additives, the directional arrangement on the surface of the plating bath can promote the uniform dispersion of Pb2+, when PbO2 is deposited, the surface is coated, the particle aggregation is reduced, and the coating is flatter and denser; at the same time, due to the adsorption of organic additives, the preferred orientation of grains is changed, but the crystal form is not changed, the prepared electrode materials are still β-PbO2 with complete morphology and three-dimensional porous structure. With the addition of organic additives, the pore density of the electrode material is increased, the specific surface area of the electrode material is promoted, the charge transfer resistance in the electrocatalysis process is reduced, and the electrocatalytic activity of the electrode material is improved. Among all organic additives, the porous PbO2 electrodes added with SDBS has the largest j0 (5.514×10-5 A·cm-2) and the smallest Rct (0.3395 Ω·cm2), showing good electrocatalytic performance. According to the CV data, the qi* of the PbO2 electrode with SDBS is 0.652 C·cm-2, which is 4 times higher than that of the porous PbO2 electrode without additive, The addition of organic additives effectively increases the electrochemically active surface area of the electrode material.

For improving the colour diversity and corrosion resistance of current zinc-copper-titanium alloys for the construction industry，the corrosion resistance of the surface film of Zn-Cu-Ti alloy after anodic oxidation treatment was analyzed and investigated by means of polarization curve，AC impedance，simulated seawater immersion experiment and salt spray test.Results showed that the quality of the anodic oxide film increased and then decreased with the increase of the current density and the concentration of NaOH in the electrolyte.When the current density was 10 A/dm2 and the NaOH concentration was 20 g/L，the as-obtained film had the most positive self-corrosion potential and the smallest self-corrosion current density.Additionally，the anodized film layer could significantly enhance its corrosion resistance in the simulated seawater corrosion test environment.

In order to enhance the hydrophilicity and corrosion resistance of aluminum alloy surface， a hydrophilic surface was obtained on 2024 and 6061 aluminum alloy substrates by anodic oxidation，reaming and coating of sodium fluosilicate，and the surface morphology，elemental composition， wettability and electrochemical properties of the as-prepared hydrophilic surface were analyzed. Results showed that after anodizing with 15%(mass fraction) sulfuric acid solution， the oxide films of 2024 aluminum alloy and 6061 aluminum alloy presented the rough nano-particles and dispersed micropores respectively. And the oxide film of 2024 aluminum alloy could better combine with sodium fluorosilicate to form a surface film with good hydrophilic effect. These two kinds of aluminum alloys were coated in sodium fluorosilicate solution， and hydrophilic films with contact angles less than 30° were obtained. The average contact angle of 2024 aluminum alloy surface was 18.5° and both aluminum alloys obtained good hydrophilicity. The electrochemical test results showed that the corrosion resistance of 2024 and 6061 aluminum alloys both decreased after coating， and the corrosion resistance of 6061 aluminum alloy changed more obviously. In all， the hydrophilicity and corrosion resistance of 2024 aluminum alloy were better than those of 6061 aluminum alloy after coating.