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An efficient protocol to synthesize aryl selenoethers through deborylative selenylation of widely available arylboronic acids has been established under electrochemical conditions in the absence of metal catalyst and external oxidant. The synthesis of bioactive molecules and gram-scale transformation have been performed to highlight synthetic utility of the protocol. CV (cyclic voltammetry) experiment indicates that anodic oxidation of diselenide occurs prior to that of arylboronic acid substrate under the standard conditions.indicates that anodic oxidation of diselenide occurs prior to that of arylboronic acid substrate under the standard conditions.

Hee-Seon Kim1 *, Min-Kyung Ji2 *, Woo-Hyung Jang1 *, Khurshed Alam,3 Hyun-Seung Kim,4 Hoon-Sung Cho,3 Hyun-Pil Lim1 1Department of Prosthodontics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea; 2Optoelectronics Convergence Research Center, Chonnam National University, Gwangju, 61186, Republic of Korea; 3Department of Materials Science and Engineering, Chonnam National University, Gwangju, 61186, Republic of Korea; 4Department of Division of New Projects, KJ Meditech Co, Ltd, Gwangju, 61009, Republic of Korea*These authors contributed equally to this workCorrespondence: Hyun-Pil LimDepartment of Prosthodontics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of KoreaTel +82-10-2645-7528Fax +82-62-530-5577Email mcnihil@jnu.ac.krHoon-Sung ChoDepartment of Materials Science and Engineering, Chonnam National University, Gwangju, 61186, Republic of KoreaTel +82-10-8545-2816Fax +82-62-530-1717Email cho.hoonsung@jnu.ac.krPurpose: This paper presents a technique for developing a novel surface for dental implants using a combination of nitriding and anodic oxidation, followed by the deposition of graphene oxide using atmospheric plasma. The effects of various surface treatments on bacterial adhesion and osteoblast activation were also evaluated.Methods: CP titanium (control) was processed into disk-shaped specimens. Nitriding was conducted using vacuum nitriding, followed by anodic oxidation, which was performed in an electrolyte using a DC power supply, to form the novel “mulberry surface.” Graphene oxide deposition was performed using atmospheric plasma with an inflow of carbon sources. After analyzing the sample surfaces, antibacterial activity was evaluated using Streptococcus mutans and Porphyromonas gingivalis bacteria. The viability, adhesion, proliferation, and differentiation of osteoblasts were also assessed. Analysis of variance (ANOVA) with Tukey’s post-hoc test was used to calculate statistical differences.Results: We observed that the mulberry surface was formed on samples treated with nitriding and anodic oxidation, and these samples exhibited more effective antibacterial activity than the control. We also found that the samples with additional graphene oxide deposition exhibited better biocompatibility, which was validated by osteoblast adhesion, proliferation, and differentiation.Conclusion: The development of the mulberry surface along with graphene oxide deposition inhibits bacterial adhesion to the implant and enhances the adhesion, proliferation, and differentiation of osteoblasts. These results indicate that the mulberry surface and graphene oxide deposition together can inhibit peri-implantitis and promote osseointegration.Keywords: nitriding, anodic oxidation, atmospheric plasma, biofilm formation, osteoblasts

In sharp contrast to hypervalent iodine(III) compounds, the isoelectronic bromine(III) counterparts have been little studied to date. This knowledge gap is mainly attributed to the difficult‐to‐control reactivity of λ 3‐bromanes as well as to their challenging preparation from the highly toxic and corrosive BrF3 precursor. In this context, we present a straightforward and scalable approach to chelation‐stabilized λ 3‐bromanes by anodic oxidation of parent aryl bromides possessing two coordinating hexafluoro‐2‐hydroxypropanyl substituents. A series of para‐substituted λ 3‐bromanes with remarkably high redox potentials spanning a range from 1.86 V to 2.60 V vs. Ag/AgNO3 was synthesized by the electrochemical method. We demonstrate that the intrinsic reactivity of the bench‐stable bromine(III) species can be unlocked by addition of a Lewis or a Brønsted acid. The synthetic utility of the λ 3‐bromane activation is exemplified by oxidative C−C, C−N, and C−O bond forming reactions., A straightforward electrochemical synthesis of chelation‐stabilized hypervalent bromine(III) compounds is presented. The electrolysis proceeds at room temperature in an undivided cell under galvanostatic conditions, giving λ 3‐bromanes in good yields on the gram scale from bromoarenes. The reactivity of λ 3‐bromanes can be enhanced by Lewis or Brønsted acid additives as demonstrated in λ 3‐bromane‐mediated oxidative biaryl formation.

The effect of chalcogenophosphoryl fragments on the anodic oxidation of 9-chalcogenophosphoryl-9,10-dihydroacridines was studied in detail. The data of X-ray structural analyses, quantum chemical calculations, and cyclic voltammetry measurements obtained for these compounds provide an explanation of the observed features. The direct electrochemical phosphorylation of acridine was first carried out successfully.

Titanium implants have been widely used as one of the most effective treatments of bone defects. However, the lack of osteogenesis and bacteria-resistant activities result in high infection and loosening rates of titanium implants. Anodic oxidation could easily construct titanium dioxide nanotubes (TNTs) array on the surface of titanium, and the rough surface of TNTs is beneficial to the growth of osteoblast-related cells on the surface. And TNTs could be excellent drug carriers because of their single-entry tubular hollow structure. In this review, we aim at detailing the application of TNTs as drug carriers in the field of bone implants. Starting from the topography of TNTs, we illustrated the biological activity of the TNTs surface, the drugs for loading in TNTs, and the controlled and responsive release strategies of drug-loaded TNTs, respectively. At the end of this review, the shortcomings of TNTs as the drug carrier in the field of bone implants are discussed, and the development direction of this research field is also prospected.

The work is devoted to the theoretical and experimental study of the electrochemical characteristics of the closo-decaborate anion. The regions of electrochemical transformations of the [B10H10]2– anion for non-aqueous solvents of different structures (acetonitrile, dichloromethane, and tetrahydrofuran) have been studied by the method of cyclic voltammetry. It has been shown that, under the conditions of anodic oxidation, a dimerization product, the [B20H18]2– anion, is formed. For the synthesis of octadecahydroeicosaborate anion, electrochemical synthesis has been used for the first time.

A convenient and efficient method for the generation of iminoxy radical through the anodic oxidation was developed for the synthesis of 3,5-disubstituted 1,2,4-oxadiazoles from N-benzyl amidoximes. The transformation undergoes 1.5-Hydrogen Atom Transfer (1,5-HAT) and intramolecular cyclization. The process features simple operation, mild conditions, broad substrate scope and high functional group compatibility, and provides a facile and practical way for the preparation of 1,2,4-oxadiazoles.

An anodic oxidation process with graphite anode coated with lead dioxide (G/β-PbO2) was optimized for the degradation of methylene blue (MB) and the treatment of real textile wastewater. The G/β-PbO2 anode was prepared by the electrochemical precipitation method. The scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analyses confirmed the successful coating of graphite substrate with the β-PbO2 film. The effect of four independent variables including pH, reaction time, current density, and electrolyte concentration of Na2SO4 on the performance of the electrochemical oxidation system was modeled by using a complete central composite design and was then optimized by genetic algorithm method. The accuracy of the proposed quadratic model by CCD was confirmed with p-value 0.9. The optimum conditions for solution pH, reaction time, current density, and Na2SO4 electrolyte concentration were obtained to be 5.75, 50 min, 10 mA/cm2, and 78.8 mg/L, respectively. In these conditions, the experimental removal efficiencies of MB using G/β-PbO2 and graphite anodes were 96.2% and 68.3%, respectively. The electrochemical removal of MB using both G/β-PbO2 and graphite anodes well followed the pseudo-first-order reaction (R2 > 0.9). Cyclohexane, cyclohexa-2,5-dien-1-ylium, and N-(sec-butyl) aniline were the most abundant intermediates identified by LC-MS analysis. However, the complete mineralization of MB was achieved in 60 min. The optimized anodic oxidation process successfully improved the biodegradability of real textile wastewater ( B O D / C O D > 0.4 ).

Electrochemistry provides a valuable toolbox for organic synthesis and offers an appealing, environmentally benign alternative to the use of stoichiometric quantities of chemical oxidants or reductants. Its potential to control current efficiency along with providing alternative reaction conditions in a classical sense makes electrochemistry a suitable method for large-scale industrial transformations as well as for laboratory applications in the synthesis of complex molecular architectures. Even though research in this field has intensified over the recent decades, many synthetic chemists still hesitate to add electroorganic reactions to their standard repertoire, and hence, the full potential of preparative organic electrochemistry has not yet been unleashed. This short review highlights the versatility of anodic transformations by summarizing their application in natural product synthesis.1 Introduction2 Shono-Type Oxidation3 C–N/N–N Bond Formation4 Aryl–Alkene/Aryl–Aryl Coupling5 Cycloadditions Triggered by Oxidation of Electron-Rich Arenes6 Spirocycles7 Miscellaneous Transformations8 Future Prospects

A new electrochemical methodology has been developed for the preparation of a wide variety of functionalized orthoesters under mild and green conditions from easily accessible dithiane derivatives. The new methodology also offers an unprecedented way to access tri(fluorinated) orthoesters, a class of compound that has never been studied before. This provides the community with a rapid and general method to prepare libraries of functionalized orthoesters from simple and readily available starting materials.

The optimisation process of the orthogonal experiment was designed by Taguchi experiment. Nanopores structure was prepared on the surface of stainless steel by anodic oxidation in the nitric acid s...

By applying a three-step anodic oxidation method followed by etching and pore widening treatment, etched micro-/submicroscale pits of ∼2 μm and ∼230 nm as well as anodized nanopores of ∼70 nm are c...

The oxidative ring opening of lignin-derived alkylated cyclohexanols to bio-based alkylated dicarboxylic acids is successfully performed by an electrocatalytic conversion. To establish this transformation as a green method, we developed a simple protocol for the anodic oxidation at nickel oxide-hydroxide (NiOOH) foam anodes in caustic soda in both a batch and flow electrolysis approach.

A simple and sustainable one-step strategy for the preparation of electron-deficient aryl trifluoromethyl ethers (ArOCF3) from the corresponding phenols by electrochemical synthesis is presented. Anodic oxidation of trifluoromethane sulfinate (Langlois reagent) leads to direct O-trifluoromethylation of phenol-derivatives bearing fluorine, chlorine, bromine and nitrile substituents under mild conditions in yields up to 75% and in gram-scale. This electrochemical protocol provides an economic and green synthesis for an otherwise inaccessible class of molecules without the need for expensive or toxic reagents, oxidants or metal catalysts.

Caffeine is one of the most widely detected and reported emerging contaminant in wastewater, groundwater as well as fresh and marine water bodies owing to its massive consumption, which has led to the bioaccumulation of caffeine in different aquatic environment. Hazardous effects of caffeine have been reported on aquatic biota, coral reefs, soil and microorganisms along with the detrimental health impact on humans. Conventional wastewater treatment plants have shown fairly high removal of caffeine ranging from 64% to 100%. However, caffeine is only partially biodegraded in biological units and is often reported in primary and secondary sludge. The present review article elucidates different electrochemical advanced oxidation processes (EAOPs), namely anodic oxidation (AO) and electro-Fenton (EF) process as alternative techniques for caffeine removal from wastewater and highlights their major findings. Additionally, information regarding performance of integrated systems comprising EAOPs and conventional technologies as well as state-of-art hybrid technologies, such as bioelectro-Fenton (BEF), photoelectron Fenton (PEF) have also been discussed to incorporate a broader perspective of EAOPs as a promising wastewater treatment technique. The review also intends to assist the readers in understanding the key challenges encountered during the operation of EAOPs and the critical parameters affecting removal efficiency along with the potential areas for future investigations for overcoming the drawbacks of EAOPs to make it sustainable technology for field-scale applications.

This work concerns the development of a method of functionalization of the surface of the biomedical Ti–6Al–7Nb alloy by producing oxide nanotubes (ONTs) with drug-eluting properties. Shaping of the morphology, microstructure, and thickness of the oxide layer was carried out by anodization in an aqueous solution of 1 M ethylene glycol with the addition of 0.2 M NH4F in the voltage range 5–100 V for 15–60 min at room temperature. The characterization of the physicochemical properties of the obtained ONTs was performed using SEM, XPS, and EDAX methods. ONTs have been shown to be composed mainly of TiO2, Al2O3, and Nb2O5. Single-walled ONTs with the largest specific surface area of 600 cm2 cm−2 can be obtained by anodization at 50 V for 60 min. The mechanism of ONT formation on the Ti–6Al–7Nb alloy was studied in detail. Gentamicin sulfate loaded into ONTs was studied using FTIR, TG, DTA, and DTG methods. Drug release kinetics was determined by UV–Vis spectrophotometry. The obtained ONTs can be proposed for use in modern implantology as carriers for drugs delivered locally in inflammatory conditions.

A simple and mild protocol for copper-catalyzed bromination of quinoline at the C5 site of quinoline by anodic oxidation was developed, affording the desired remote C–H activation products with iso...

The cleavage of C–O–C linkage is a critical step in the degradation of diaryl ether contaminants and lignin, which holds great significance of environmental protection and lignocellulosic biomass u...

A metal-free convergent paired electrolysis strategy to synthesize benzylic amines through direct arylation of tertiary amines and benzonitrile derivatives at room temperature has been developed. This TEMPO-mediated electrocatalytic reaction makes full use of both anodic oxidation and cathodic reduction without metals or stoichiometric oxidants, thus showing great potential and advantages for practical synthesis. This convergent paired electrolysis method provides a straightforward and powerful means to activate C-H bonds and realize cross-coupling with cathodically generated species.

Modifying the geometric and surface parameters of oriented TiO2 nanotubes (NTs) is beneficial to the utilization of solar energy for chemical reactions, and this performance may be further improved. Thus, the effects of adding an ionic liquid (IL), 1-butylpiridinium chloride [BPy][Cl], and the effects of the water content and preparation conditions on the surface morphological, physicochemical, photocatalytic, and photoelectrochemical properties of TiO2 NTs were thoroughly examined and presented. The anodic oxidation of Ti foil in an organic electrolyte containing a small amount of [BPy][Cl] allowed for obtaining IL_NTs with a well-ordered structure, even at low voltages (10 V). Additionally, the application of [BPy][Cl] enabled one of the geometric parameters of the IL_NTs, namely, the diameter, to be tuned, whereas the length remained the same (i.e., control over the diameter was first noted). Improvements in the photocatalytic and photoelectrochemical activities of the IL_NTs in comparison with those o...

The comparison of the degradation efficiency of two electrodes (Ti/RuO2–IrO2 and SnO2) has been evaluated using Methylene Bleu (MB) dye. The effect of several parameters on the degradation process ...

The nanoscaled profiling of a silicon 5 (111) n-type substrate surface is studied by the local anodic oxidation (LAO). Varying the voltage pulse amplitude from 5 to 12.5 V and the humidity from 30 ± 1 to 70 ± 1% during the LAO is a promising way to form oxide structures with heights from 0.5 ± 0.3 to 2.1 ± 0.1 nm and profiled structures with depths from 0.4 ± 0.3 to 1.5 ± 0.2 nm on the substrate. The results can be applied to the development of technological processes of the element base of silicon-based nanoelectronics using the probe nanotechnologies.

An ultrasonic-assisted electrochemical mechanical polishing (UAECMP) technique that combines ultrasonic vibration and electrochemical mechanical polishing (ECMP) is proposed. The effect of ultrasonic vibration on the anodic oxidation rate of a 4H-SiC (0001) surface was studied, and it was confirmed that ultrasonic vibration significantly enhanced the anodic oxidation of SiC. Compared with conventional anodic oxidation, the oxidation rate increased by about 34% with ultrasonic assistance (UA) in the initial oxidation stage, and by about 11% during subsequent anodic oxidation. In addition, the oxidation can be promoted continuously with increasing oxidation time owing to the porous structure of the oxide layer. UAECMP is very promising as an efficient finishing technique for SiC surfaces. Keywords: Silicon carbide, Ultrasonic-assisted electrochemical mechanical polishing, Ultrasonic-assisted anodic oxidation, Ultrasonic vibration

A dehydroxylative Csp3-N coupling reaction assisted by triphenylphosphine has been developed through electrochemical oxidation. The reaction proceeds via anodic oxidation of triphenylphosphine to generate its corresponding radical cation, followed by reacting with hydroxyl groups to form alkoxy triphenylphosphonium ions, which are trapped by azoles or amides to construct C-N bonds. This method provides an efficient electrochemical strategy of activating hydroxyl groups to form C-N bonds under mild conditions.

In recent years, electrochemical methods utilizing reactive electrochemical membranes (REM) have been recognized as the most promising technologies for the removal of organic pollutants from water. In this paper, we propose a 1D convection-diffusion-reaction model concerning the transport and oxidation of oxalic acid (OA) and oxygen evolution in the flow-through electrochemical oxidation system with REM. It allows the determination of unknown parameters of the system by treatment of experimental data and predicts the behavior of the electrolysis setup. There is a good agreement in calculated and experimental data at different transmembrane pressures and initial concentrations of OA. The model provides an understanding of the processes occurring in the system and gives the concentration, current density, potential, and overpotential distributions in REM. The dispersion coefficient was determined as a fitting parameter and it is in good agreement with literary data for similar REMs. It is shown that the oxygen evolution reaction plays an important role in the process even under the kinetic limit, and its contribution decreases with increasing total organic carbon flux through the REM.

To realize the connection of copper and Polyphenylene sulfide (PPS) by metal–polymer direct molding, this paper combined anodic oxidation and chemical corrosion to treat the surface of copper, and carried out the injection molding experiment. An orthogonal experimental arrangement was used to identify the optimal electrolyte and etching solution for preparing a microstructure on a copper surface. The bonding and fracture mechanisms of the copper–polymer assembly were investigated through injection molding experiment and SEM technology. The results revealed that the phosphoric acid concentration had the most significant effect on the microstructure quality and etching solution containing 20% phosphoric acid produced a uniform microstructure with 25.77% porosity and 5.52 MPa bonding strength. Meanwhile, SEM images of the interface from bonding to fracture in the copper–polymer assembly indicated a well-filled polymer in the microstructure with a mainly cohesive fracture mode.

Photocatalysis has long been touted as one of the most promising technologies for environmental remediation. The ability of photocatalysts to degrade a host of different pollutants, especially recalcitrant molecules, is certainly appealing. Titanium dioxide (TiO2) has been used extensively for this purpose. Anodic oxidation allows for the synthesis of a highly ordered nanotubular structure with a high degree of tunability. In this study, a series of TiO2 arrays were synthesised using different electrolytes and different potentials. Mixed anatase-rutile photocatalysts with excellent wettability were achieved with all the experimental iterations. Under UVA light, all the materials showed significant photoactivity towards different organic pollutants. The nanotubes synthesised in the ethylene glycol-based electrolyte exhibited the best performance, with near complete degradation of all the pollutants. The antibacterial activity of this same material was similarly high, with extremely low bacterial survival rates. Increasing the voltage resulted in wider and longer nanotubes, characteristics which increase the level of photocatalytic activity. The ease of synthesis coupled with the excellent activity makes this a viable material that can be used in flat-plate reactors and that is suitable for photocatalytic water treatment., peer-reviewed

Natural products have played a significant role not only in discovery of drugs but also in development of organic chemistry by providing the synthetic challenges. Inspired by biosynthesis where enzymes catalyze a multi-step reaction, we have investigated the natural product synthesis utilizing electrochemical reactions as the key step. Electrochemical organic synthesis, so-called electro-organic synthesis, enables to control the reactivity of substrates simply by tuning electrolysis conditions. In this Personal Account, we overview the recent progress of our research projects about natural product synthesis, in which anodic oxidation of phenol compounds affords the important frameworks such as diaryl ether, spirodienone, and spiroisoxazoline.

The present paper aims to valorize the use of cheap agricultural waste materials for polluted water decontamination. An evaluation of the efficiency of coupling anodic oxidation (AO) using SS/PbO 2 electrodes with biosorption by Luffa cylindrica (L.C) for the removal of Amaranth Red (E123) from aqueous solution was investigated. The effects of pH, contact time, and initial concentration were studied. The regeneration of L.C was estimated based on biosorption /desorption tests. The performance of the coupling process was evaluated based on the color, chemical organic carbon (COD), Total organic carbon (TOC) removals, the energy consumed, and the time required for the degradation of Amaranth. A comparison between the efficiency of the AO and the coupling process for the increase of the lifetimes of the anodes used was done. 54.1, 97.8, and 99.9% of 50 mg.L -1 of Amaranth were removed respectively after 85, 65, and 50 min by biosorption, AO, and coupling AO with biosorption. An increase in the percentages of COD, TOC, germination indexes (GI), and Amaranth removals were observed when adopting the coupling process. Furthermore, a decrease in the release of Pb 2+ ions was observed confirming the good stability of the elaborated anodes during the coupling process. Atomic absorption analysis showed that the Pb 2+ ions reached about 0.020 mg.L -1 , after the total removal of Amaranth dye (60 min) and 0.051 after (80 min) respectively, for coupling AO with biosorption and the AO process. These values are inferior to those allowed by the Standards. Phytotoxicity tests confirmed the possibility of the reuse of the treated solutions.

In this study anodic oxidation of Cr2(SO4)3 was carried out in an air-sparged divided parallel plate cell. Variables studied were current density, Cr2(SO4)3 concentration, and superficial air veloc...

Aziridines are useful synthetic building blocks, widely employed for the preparation of various nitrogen-containing derivatives. As the current methods require the use of prefunctionalized amines, the development of a synthetic strategy towards aziridines, that can establishe the union of alkenes and amines, would be of great synthetic value. Herein, we report an electrochemical approach, which realizes this concept via an oxidative coupling between alkenes and primary alkyl amines. The reaction is carried out in an electrochemical flow reactor, leading to short reaction times (5 min), high yields and broad scope. At the cathode, hydrogen is generated, which can be used in a second reactor to reduce the aziridine, yielding the corresponding hydroaminated product. Mechanistic investigations and DFT calculations revealed that the alkene is first anodically oxidized and subsequently reacted with the amine coupling partner.

The relative oxidation power of dimensionally stable anodes, namely Ti/Ir-Pb, Ti/Ir-Sn, Ti/Ru-Pb, Ti/Pt-Pd and Ti/RuO₂, has been determined from the anodic oxidation (AO) treatment of 2 dm³ of methyl orange azo dye solutions in 0.050 mol dm¯³ Na₂SO₄ of pH 7.0 at constant current density. The anodes were synthesized by the dip-coating method using the corresponding metallic chlorides in isopropanol/water and their morphology, surface roughness, crystallographic structure and composition were analyzed. A mixture of IrO₂, Pb₂O₃ and Pb₃O₄ were the components in the outperforming Ti/Ir-Pb anode. The effect of current density, Na₂SO₄ concentration, and cathode nature on the decolorization of azo dye solutions by AO with Ti/RuO₂ was examined. Under favorable conditions, 96%-98% color removal was achieved using Ti/Ir-Pb, Ti/Ir-Sn and Ti/Ru-Pb, with lower decolorization for Ti/Pt-Pd and Ti/RuO₂ anodes. In all cases, a pseudo-first-order decolorization process was found. The oxidation ability of anodes rose in the order Ti/RuO₂< Ti/Pt-Pd < Ti/Ru-Pb < Ti/Ir-Sn < Ti/Ir-Pb, achieving 76.0% mineralization for the latter electrode. The mixture of active and non-active materials then gave rise to anodes with higher oxidation power than those made solely of active materials, due to the enhancement of the oxidation action of hydroxyl radicals formed in the non-active oxide. The superiority of Ir over Ru in the mixed metal oxides was related to the greater adsorption of organics on its surface, thereby favoring their oxidation. Ammonium and sulfate ions were released as pre-eminent ions. Stable byproducts and final short-linear aliphatic carboxylic acids were identified by gas chromatography-mass spectrometry and ion-exclusion high-performance liquid chromatography. Based on these compounds, a reaction sequence for methyl orange mineralization is proposed.

This study investigated the fabrication of porous fluorescent SiC using a constant voltage-controlled anodic oxidation process. The application of a high, constant voltage resulted in a spatial distinction between the porous structures formed inside the fluorescent SiC substrates, due to the different etching rates at the terrace and the large step bunches. Large, dendritic porous structures were formed as the etching process continued and the porous layer thickened. Under the conditions of low hydrofluoric acid (HF) concentration, the uniformity of the dendritic porous structures through the entire porous layer was considerably improved compared with the conditions of high HF concentration. The resulting large uniform structure offered a sizable surface area, and promoted the penetration of atomic layer-deposited (ALD) Al2O3 films (ALD&ndash, Al2O3). The emission intensity in the porous fluorescent SiC was confirmed via photoluminescence (PL) measurements to be significantly improved by a factor of 128 after ALD passivation. With surface passivation, there was a clear blueshift in the emission wavelength, owing to the effective suppression of the non-radiative recombination rate in the porous structures. Furthermore, the spatial uniformity of emitted light was examined via PL mapping using three different excitation lasers, which resulted in the observation of uniform and distinctive emissions in the fluorescent SiC bulk and porous areas.

We report a set of electrochemically regulated protocols for the divergent synthesis of ketones and β-keto esters from the same β-hydroxycarboxylic acid starting materials. Enabled by electrochemical control, the anodic oxidation of carboxylic acids proceeded in either a one-electron or a two-electron pathway, leading to a 1,4-aryl transfer or a semipinacol-type 1,2-group transfer product with excellent chemoselectivity. The 1,4-aryl transfer represents an unprecedented example of carbon-to-oxygen group transfer proceeding via a radical mechanism. In contrast to previously reported radical group transfer reactions, this 1,4-group transfer process features the migration of electron-rich aryl substituents. Furthermore, with these chemoselective electrochemical oxidation protocols, a range of ketones and β-keto esters including those possessing a challenging-to-access medium-sized ring could be synthesized in excellent yields., We report a set of electrochemically regulated protocols for the divergent synthesis of ketones and β-keto esters from the same β-hydroxycarboxylic acid starting materials.

The anodic oxidation (AO) of 30 pharmaceuticals including antibiotics, hormones, antihistaminics, anti-inflammatories, antidepressants, antihypertensives, and antiulcer agents, in solutions containing different supporting electrolytes media (0.05 M Na2SO4, 0.05 M NaCl, and 0.05 M Na2SO4 + 0.05 M NaCl) at natural pH was studied. A boron-doped diamond (BDD) electrode and a stainless-steel electrode were used as anode and cathode, respectively, and three current densities of 6, 20, and 40 mA cm−2 were applied. The results showed high mineralization rates, above 85%, in all the tested electrolytic media. 25 intermediaries produced during the electrooxidation were identified, depending on the supporting electrolyte together with the formation of carboxylic acids, NO3−, SO42− and NH4+ ions. The formation of intermediates in chloride medium produced an increase in absorbance. Finally, a real secondary effluent spiked with the 30 pharmaceuticals was treated by AO applying 6 mA cm−2 at natural pH and without addition of supporting electrolyte, reaching c.a. 90% mineralization after 300 min, with an energy consumption of 18.95 kW h m−3 equivalent to 2.90 USD m−3. A degradation scheme for the mixture of emerging contaminants in both electrolytic media is proposed. Thus, the application of anodic oxidation generates a high concentration of hydroxyl radicals that favors the mineralization of the pharmaceuticals present in the spiked secondary effluent sample., The authors are very grateful for the partial financial support of FONDECYT Grant 1170352 and DICYT USACh. W. Calzadilla thanks PFCHA/ANID for the National PhD scholarship 21160273. Authors also acknowledge the partial financial support of the Spanish Ministry of Science and Innovation through the Project ROUSSEAU CTM2017-89767-C3-1-R and Project CEX2018-000794-S.

Oriented TiO2 nanotubes, which are fabricated by anodic oxidation method, are prospective in photoelectrochemical analysis and sensors. In this work, Pt and IrO2 co-modified TiO2 nanotubes array was prepared via a two-step deposition process involving the photoreductive deposition of Pt and chemical deposition of IrO2 on the oriented TiO2 nanotubes. Due to the improved separation of photo-generated electrons and holes, Pt-IrO2 co-modified TiO2 nanotubes presented significantly higher PEC activity than pure TiO2 nanotubes or mono-modified TiO2 nanotubes. The PEC sensitivity of Pt-IrO2 co-modified TiO2 nanotubes for glutathione was also monitored and good sensitivity was observed.

Currently, the use of nanostructured films of anodic aluminum oxide (AAO) arouses great interest for a variety of nanotechnological applications. Previous studies have shown that the most important parameters in the anodic synthesis of nanoporous AAO films are the pretreatment of the substrate, the anodization voltage, and the nature, concentration and temperature of the electrolyte. To advance the development of nanomaterials, which are increasingly specific according to their functionality, in a simple and inexpensive way, it is essential to study the combined effect of the synthesis variables on the morphological properties of the coatings. The objective of this work was to study and predict the combined effect of the concentration and temperature of oxalic acid and the anodization voltage in the ordering, the pore diameter, the interpore distance, the pore density and the thickness of nanostructured films of AAO synthesized at 20, 30, 40 and 60 V and 20, 30 and 40 °C in 0.3 and 0.9 M oxalic acid, from the Al 1050 alloy. For this, surface images were obtained by optical microscopy and scanning electron microscopy, the latter being processed through the Fast Fourier Transform, and non-linear regressions were performed with the data obtained. The results proved which anodic synthesis conditions have the greatest influence on the ordering and each of the morphological parameters of the AAO films. The optimum voltage and temperature of the self-ordering regime for both oxalic acid concentrations tested were 40 V and 20 °C. The combined effect of the synthesis variables allowed obtaining coatings with a pore diameter of 27–150 nm, an interpore distance of 51–160 nm, a pore density of 35 × 108 –390 × 108 and a thickness of 10–130 μm. Fil: Bruera, Florencia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Kramer, Gustavo Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Vera, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina Fil: Ares, Alicia Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Materiales de Misiones. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Instituto de Materiales de Misiones; Argentina

The paper presents the researching results of the memristor effect on titanium oxide nanostructures obtained by local anodic oxidation. Studies have been carried out on the effect of air humidity in the process chamber during local anodic oxidation on the memristor structures main parameters. Based on oxygen vacancies distribution numerical simulation in the oxide volume formed by this method, the obtained dependences were explained. A ReRAM layout consisting of 10 memristors was developed and manufactured, and the temperature influence on its characteristics was investigated. The results can be used in the technological processes development for the formation of memristor structures based on titanium oxide nanostructures.

This paper focuses on the removal of lindane from soil washing effluents (SWEs) using combined electrochemical -biological processes. In particular, it has been evaluated the influence of the anodic material used in the electrolysis of the SWE on the biodegradability and toxicity of the effluents. Four anode materials were tested: Boron Doped Diamond (BDD), Carbon Felt (CF), and Mixed Metal Oxides Anodes with iridium and ruthenium (MMO-Ir and MMO-Ru). These materials were tested at different current densities and electric current charges applied. Lindane, TOC, sulphate, and chlorine species concentrations were monitored during electrochemical experiments, showing important differences in their evolution during the treatment. In spite of reaching a good removal of lindane with all the materials tested, results showed that Boron Doped Diamond working at 15 mA cm−2 achieved the best biodegradability results in the electrolyzed effluents, because the ratio BOD5/COD increased from 0.2 to 0.5, followed by Carbon Felt anode. Regarding toxicity, Carbon Felt decreased toxicity by 80%. Opposite to what it was expected, MMO anodes did not achieve biodegradability improvement and they only showed reduction in toxicity at high electrical charges.