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Biomass‐derived 5‐hydroxymethyl furfural (5‐HMF) is a promising starting substrate for producing two high value‐added products 2,5‐diformylfuran (DFF) and 2,5‐furandicarboxylic acid (FDCA). DFF, which is produced by selectively oxidizing the hydroxymethyl group of 5‐HMF to an aldehyde group, has many applications in pharmaceuticals, macrocyclic ligands and fluorescent materials. Oxidizing both aldehyde and hydroxymethyl groups of 5‐HMF leads to FDCA, which is an important monomer in the production of a bioplastic polyethylene furanoate polymer. Electrochemical conversion of 5‐HMF is a potential route for sustainable chemical production of DFF and FDCA. In fact, using 2,2,6,6‐tetramethyl‐ piperidine‐1‐oxyl (TEMPO) as a redox mediator leads to a highly efficient and selective electro‐oxidation of 5‐HMF into FDCA in a basic buffer solution. In this report, the direct and TEMPO‐mediated electro‐oxidation of 5‐HMF was investigated in various organic and hydro‐organic media at room temperature. Direct electro‐oxidation leads to a low selective conversion of 5‐HMF to DFF (10 % of yield) and the formation of unwanted products such as formic acid and protoanemonin (90 % and 37 % of yield respectively) in acetonitrile. Electrocatalytic 5‐HMF conversion in the presence of TEMPO as a redox mediator achieved a near‐quantitative yield of DFF in acetonitrile and γ‐valerolactone. Importantly, we demonstrate the role of water in the conversion of aldehydes to carboxylic acids. [ABSTRACT FROM AUTHOR]

Conventional plasma electrolytic oxidation treatments produce oxide coatings with micron-scale discharge pores, resulting in insulation and wear and corrosion resistance far below that expected of highly dense Al2O3 coatings. The introduction of cathodic polarization during the plasma electrolytic oxidation process, especially when the applied cathode-to-anode current ratio (Rpn) is greater than 1, triggers a unique plasma discharge phenomenon known as "soft sparking". The soft spark discharge mode significantly improves the densification of the anode ceramic layer and facilitates the formation of the high-temperature α-Al2O3 phase within the coating. Although the soft spark discharge phenomenon has been known for a long time, the growth behavior of the coating under its discharge mode still needs to be studied and improved. In this paper, the growth behavior of the coating before and after soft spark discharge is investigated with the help of the micro-morphology, phase composition and element distribution of a homemade fixture. The results show that the ceramic layer grows mainly along the oxide–electrolyte direction before the soft spark discharge transformation; after the soft spark discharge, the ceramic layer grows along the oxide–substrate direction. It was also unexpectedly found that, under soft spark discharge, the silicon element only exists on the outside of the coating, which is caused by the large size and slow migration of SiO32−, which can only enter the ceramic layer and participate in the reaction through the discharge channel generated by the strong discharge. In addition, it was also found that the relative phase content of α-Al2O3 in the coating increased from 0.487 to 0.634 after 10 min of rotary spark discharge, which is an increase of 30.2% compared with that before the soft spark discharge transition. On the other hand, the relative phase content of α-Al2O3 in the coating decreased from 0.487 to 0.313 after 20 min of transfer spark discharge, which was a 55.6% decrease compared to that before the soft spark discharge transformation. [ABSTRACT FROM AUTHOR]

PdCoNi trimetallic catalysts attracted extensive interest in direct formic acid fuel cells due to high poisoning resistance and high activity for formic acid electro‐oxidation (FAO). Herein, a series of Pd0.75CoxNiy/C alloys with a modulated ratio of Co and Ni are synthesized to investigate the effect of Co and Ni content on the electronic structure of Pd for FAO. The physical analysis demonstrated that the introduction of Co and Ni induces the lattice strain effect compared to monometallic Pd catalysts. As a consequence of fixing the total amount of Co and Ni, the strain effect is restricted, and the electronic perturbation of Pd is successfully regulated by varying the ratio of Co and Ni in Pd0.75CoxNiy/C trimetallic alloys. Pd loses more electrons, the bond strength of Pd−H is weakened, and FAO activity is enhanced first and then decreased as the Co content increases. Among the trimetallic catalysts, Pd0.75Co0.125Ni0.125/C trimetallic catalyst exhibits the highest current density of 3.253 mA cm−2 owing to the optimum electronic perturbation and Pd−H bond strength. This work provides a valuable guideline for future studies of Pd‐based trimetallic alloys. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction at the anode consumes about 60–70% of the total power for the solid oxide electrolysis cell (SOEC), and power consumption can be greatly reduced by introducing hydrocarbon fuels such as methane into the anode for the oxidation reaction. In this work, rare-earth doped CeO 2 is used as catalyst support and oxygen ion conductor with Ni serving as an active metal for methane oxidation at the SOEC anode. The catalyst is synthesized via stepwise hydrolysis and impregnation methods, and the influences of rare-earth oxides on the performance of CH 4 thermal oxidation, SOEC anode oxidation and hydrogen production are studied. The results show that 5%Ni–Ce 0.8 Gd 0.2 O 2-δ exhibits the optimal catalytic oxidation and electrolytic hydrogen production with the lowest cell voltage of 0.38 V at 0.4 A/cm2. The high performance is mainly attributed to the oxygen vacancy, oxygen ion conductivity, and active metal dispersion. It is supposed that oxygen evolution reaction and simultaneous methane oxidation with generated oxygen occur at the SOEC anode can reduce oxygen partial pressure, which results in the ultra-low voltage for hydrogen production. [Display omitted] • Optimized oxygen vacancy and oxygen ion conductivity of rare-earth doped CeO 2 enhance the electrochemical oxidation. • The SOEC anode of Gd-doped CeO 2 realizes an ultra-low voltage of 0.38 V at 0.4 A/cm2. • OER and subsequently CH 4 oxidation is proposed for anode reactions to reduce operation voltage. [ABSTRACT FROM AUTHOR]

As a result of radiation-initiated telomerization of tetrafluoroethylene (TFE) in a number of solvents, colloidal solutions of R1(C2F4)nR2 telomeres with different terminal functional groups R1 and R2 were obtained. The value of n and various end groups R1, R2 determine the properties of the obtained telomeres (solubility, adhesion, antifriction, hydrophobic, etc.). Some promising areas of use of TFE telomeres are considered: 1) production of functional hybrid polymer composite materials for aviation and rocket technology based on epoxy binders and functionalized nanotubes modified with TFE telomeres; 2) hydrophobization of highly porous materials based on quartz fibers (TQF and TZMK-10) and coatings based on fluorolacids; 3) modification of epoxy carbon fiber; 4) formation of protective composite coatings on metals and alloys using plasma electrolytic oxidation (PEO); 5) modification of the properties of natural cellulose-containing composite materials; 6) synthesis of new TFE telomeres with perfluorinated end functional links. [ABSTRACT FROM AUTHOR]

Hemodialysis treatment in specialized clinics within the same hospital significantly impacts environmental water health due to contaminated wastewater. The issues observed included changes in electrical conductivity, the presence of dangerous bacterial loads, toxicity from heavy metals, total cyanide content, and helminth parasite eggs. The level of damage is dependent on the patient's health under treatment. This research will use a modular system that employs electrocoagulation and electro‐oxidation processes at the laboratory and pilot levels to treat hemodialysis wastewater using synthetically prepared and real samples extracted from local clinics. The results showed that these hybrid systems improved various physicochemical parameters. Specifically, decreases in electrical conductivity of 49 %, total suspended solids of 27–100 %, chemical oxygen demand of 49 %, biochemical oxygen demand of 49 %, and cation and anion loading were observed at 96–100 % and pH 8.13 UpH in accordance with the established standards. With these results and the experimental conditions used, the proposed treatment system was modeled using the GPS‐X program, and it was concluded that the modular system used and the electrocoagulation/electro‐oxidation/activated carbon configuration is suitable for treating wastewater from hemodialysis and that scaling up this process to facilities that have dialysate machines more advanced than those considered in this work is possible. [ABSTRACT FROM AUTHOR]

In this study, we successfully employed the plasma electrolytic oxidation (PEO) technique to create a uniform white ceramic layer on the surface of the 6061 aluminum alloy using K2ZrF6 and Na2WO4 as colorants. A scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS) and X-ray diffraction (XRD) were used to characterize the coatings, and we used an electrochemical workstation to test their corrosion protection properties. The corrosion resistance of the coatings was analyzed using potentiodynamic polarization curves. The results showed that K2ZrF6 addition whitened the coating with ZrO2 as the main phase composition, inhibiting Al substrate depletion and enhancing coating corrosion resistance. A small amount of Na2WO4 decreased the coating's L* value, successfully constructing ceramic coatings with L* (coating brightness) values ranging from 70 to 86, offering broad application prospects for decorative coatings. [ABSTRACT FROM AUTHOR]

To enhance the tribological properties of TC4 alloy, the plasma electrolytic oxidation (PEO) method was utilized to prepare the coating incorporated various contents of Al 2 O 3 nanoparticles (0, 3, 6, 9, 12 and 15 g/L) on TC4 alloy. The phase composition, chemical compositions, elemental distribution and microstructure of the coatings were investigated by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and X-ray computer tomography (XCT). The results revealed that the introduction of Al 2 O 3 nanoparticles into the electrolyte promoted the formation of Al 2 TiO 5 phase in the PEO coatings, and most of the nanoparticles were embedded into the coatings which reduced porosity of the coatings, but increased surface roughness. Also, the increase in the addition of Al 2 O 3 nanoparticles enhanced the microhardness of the PEO coatings due to the formation of Al 2 TiO 5. The tribological behavior of the PEO coatings was improved significantly owing to the high microhardness and porous structure of the coatings. The primary wear mechanism of the coating with 12 g/L Al 2 O 3 nanoparticles was abrasive wear as this coating formed a lubrication zone during the wear process. Besides, the friction coefficient and wear loss mass of the PEO coating prepared with 12 g/L Al 2 O 3 nanoparticles additive exhibited the excellent wear resistance compared to its counterparts. [ABSTRACT FROM AUTHOR]

• Coatings with Ta 2 O 5 nanoparticles were successfully formed on Mg. • It was found that incorporation of Ta 2 O 5 nanoparticles increases roughness and porosity of the PEO layers contributing into sufficient soft tissue ingrowth in vivo. • The cell morphology indicates good histocompatibility of the obtained coatings and intensive tissue ingrowth. • It was found that incorporation of the Ta 2 O 5 nanoparticles elicits higher rates of apatite layer formation. The present study investigates the physical and chemical characteristics, behavior in vitro and in vivo , and biocompatibility of coatings containing Ta 2 O 5 , which are obtained by plasma electrolytic oxidation (PEO) on MA8 magnesium alloy. The obtained coatings demonstrate in vivo biocompatibility and in vitro bioactivity. Compared to the base PEO coating, the layers containing Ta 2 O 5 facilitate the development of apatite in simulated body fluid, suggesting that the inclusion of nanoparticles improves bioactivity of the coatings. It was found that incorporation of Ta 2 O 5 nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in vivo. Based on in vivo studies, these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen evolution. The results obtained in the present study concluded biocompatibility, tissue integration of the PEO coatings containing Ta 2 O 5 nanoparticles making them a promising protective layer for biodegradable magnesium implants. [Display omitted] [ABSTRACT FROM AUTHOR]

• A novel electron-transfer MOF material was synthesized and deposited onto the porous coating of AZ31Mg alloy. This material was modified by transition metallic oxides. • The electronic structures of SnOF, ZnOF, and VOF complexes varied, impacting the morphologies of the samples and influencing their electrochemical and photocatalytic activities. • SnOF aggregation on the PEO layer sealed structural defects, creating a barrier against corrosive ion infiltration and resulting in high electrochemical stability. • SnOF and VOF samples showed high efficiency in crystal violet degradation after exposure to visible light. VOF demonstrated remarkable efficiency and stability, surpassing the performance of previously reported catalysts. • The degradation mechanism and the interaction between crystal violet and the catalyst were thoroughly examined, along with the reactive species responsible for degradation. In the pursuit of multifunctional coatings, the controlled growth of materials on stationary platforms holds paramount importance for achieving superior corrosion protection and optimal photocatalytic performance. This study introduces a cutting-edge approach, intertwining bifunctional metal-organic frameworks (MOFs) seamlessly into defective MgO layers produced by the anodic oxidation of AZ31 alloy. Key metallic oxides of Zn, Sn, and V take center stage as metallic sources for MOF formation, complemented by the organic prowess of l -Tryptophan as an α-amino acid linker. Leveraging the electronic structure of metallic oxides reacting with tryptophan molecules, controlled morphologies with distinct characteristics are induced on the defective surface of the MgO layer, enabling the precise modulation of surface defects. The hybrid composite demonstrates an adaptive microstructure in diverse aqueous environments, offering dual functionality with electrochemical stability and visible light photocatalytic activity for crystal violet degradation. Among the samples, the SnOF complex exhibited remarkable electrochemical stability with a low corrosion current density of 7.50 × 10−10 A·cm−2, along with a 94.56 % degradation efficiency after 90 min under visible light exposure. The VOF complex, under similar visible light conditions, demonstrated exceptional performance with a higher degradation efficiency of 97.79 % and excellent electrochemical stability characterized by a corrosion current density of 3.26 × 10−9 A·cm−2. Additionally, Density Functional Theory (DFT) computations shed light on the basic bonding patterns between MOFs and inorganic components, providing electronic understanding of their electrochemical and photocatalytic activities. [Display omitted] [ABSTRACT FROM AUTHOR]

• Low-energy PEO coatings were grown on Mg–Li alloy in presence of ionic liquid. • The corrosion resistance of low-energy PEO coating with ionic liquid was enhanced. • The role of ionic liquid was demonstrated by molecular dynamics simulation. • Influence of ionic liquid on the formation of LePEO coating was discussed. A low-energy plasma electrolytic oxidation (LePEO) technique is developed to simultaneously improve energy efficiency and anti-corrosion. Ionic liquids (1‑butyl‑3-methylimidazole tetrafluoroborate (BmimBF 4)) as sustainable corrosion inhibitors are chosen to investigate the corrosion inhibition behavior of ionic liquid (ILs) during the LePEO process for LA91 magnesium–lithium (Mg–Li) alloy. Results show that the ionic liquid BmimBF 4 participates in the LePEO coating formation process, causing an increment in coating thickness and surface roughness. The low conductivity of the ionic liquid is responsible for the voltage and breakdown voltage increases during the LePEO with IL process (LePEO-IL). After adding BmimBF 4 , corrosion current density decreases from 1.159 × 10−4 A·cm−2 to 8.143 × 10−6 A·cm−2. The impedance modulus increases to 1.048 × 104 Ω·cm−2 and neutral salt spray remains intact for 24 h. The superior corrosion resistance of the LePEO coating assisted by ionic liquid could be mainly attributed to its compact and thick barrier layer and physical absorption of ionic liquid. The ionic liquid-assisted LePEO technique provides a promising approach to reducing energy consumption and improving film performance. [ABSTRACT FROM AUTHOR]

In this study, the AA1100 aluminum alloy underwent the plasma electrolytic oxidation (PEO) process to enhance its adhesion to a thermoplastic composite of polyetherimide (PEI) reinforced with glass fiber, following ASTM D1002:10 standards. A 23 factorial design was employed, varying three parameters in the oxidation process: immersion time, applied electric potential, and electrolyte concentration (Na2B4O7). The joining of aluminum and thermoplastic composite samples was achieved through oxy-fuel welding (OFW), using oxygen and acetylene gases. For the characterization of the joined samples, a universal tensile testing machine was utilized with a displacement speed of 1.5 mm/min. The analysis of the oxide coating involved scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR). Through variance analysis, it was determined that the statistical model encompasses approximately 80% of the variability in the adhesion process between materials. An improvement of up to 104% in adhesion between the materials was observed with the process, indicating an effective bond due to the presence of the thermoplastic matrix in the treated aluminum sample. This improvement is attributed to the morphology of the oxide coating, resembling corals, with micro-pores and recesses that facilitated mechanical anchoring. [ABSTRACT FROM AUTHOR]

In this study, Pd/TiO2 decorated carbon nanofibers (Pd/TiO2@CNFs) and Pd@CNFs were prepared by the impregnation method for application in direct methanol fuel cells (DMFCs). Pd and TiO2 particles were supported on the surface of carbon fibers. Noticeably, When the mass fraction of PdCl2 added is 4%, the Pd@CNFs catalyst (Pd‐4@CNFs) showed higher electrocatalytic activity and stability, which were about 28.4 and 13.2 times higher than those of commercial Pd/C catalyst, respectively. On the basis of Pd‐4@CNFs catalyst, TiO2 with a mass fraction of 10% was added to produce Pd/TiO2@CNFs catalyst (Pd‐4/TiO2‐10@CNFs). The electrocatalytic activity of Pd‐4/TiO2‐10@CNFs increased to 3,850.4 A·g−1, which was 31.9 times higher than that of commercial Pd/C catalysts. These results demonstrated that the novel Pd/TiO2@CNFs catalyst is expected to be an efficient and durable catalyst for DMFC. [ABSTRACT FROM AUTHOR]

Magnesium alloys, because of their excellent strength-to-weight ratio, are increasingly used in many industries. When used in external elements, the key factor is to provide adequate anticorrosion protection. High-temperature, cured-powder coatings are widely used to protect most metals, but their use on magnesium alloys is difficult as a result of the instability of the magnesium substrate at elevated temperatures. Another problem is ensuring the proper adhesion of the organic coating to the magnesium substrate. This paper presents the procedure for the synthesis of a duplex coating on AZ91 magnesium alloy. The topcoat was a powder coating based on acrylic resin, the main ingredient of which was glycidyl methacrylate. Because of the presence of epoxy groups, the coating was cured using ultraviolet (UV) radiation (low-temperature technology). The conversion subcoating was produced by plasma electrolytic oxidation (PEO) in an alkaline silicate electrolyte. The synthesized coating system was tested, among others, for microscopic (SEM), adhesive (mesh of cuts), and anticorrosion (EIS). The duplex PEO/UV-curable powder coating showed very good adhesion to the metal and increased the anticorrosion properties of the magnesium substrate, compared to the powder coating produced directly on the magnesium alloy and on an alternative conversion coating (synthesized in the process of chemical zircon phosphating). [ABSTRACT FROM AUTHOR]

Ceramic coatings were formed on the surface of as-cast Al5.2Zn1.7Mg0.4Ni0.3Fe and heat-treated Al7.0Zn2.7Mg0.5Ni0.4Fe "nikalin" aluminum alloys by using the plasma electrolytic oxidation (PEO) technique in a silicate–alkaline electrolyte. Uniform coatings containing a minimum number of defects and consisting predominantly of a γ-Al2O3 phase were synthesized on the surface of both Al-Zn-Mg-Ni-Fe alloys. The coatings had a microhardness of 660–1200 HV, which is 3.5–11 times higher than that of the "bare" as-cast and heat-treated alloy. The coating on the Al5.2Zn1.65Mg0.4Ni0.3Fe alloy had the highest peak hardness, which is probably caused by the lower residual alloying elements Zn and Mg in the coating bulk. As a consequence, the PEO coating with the highest hardness synthesized on the as-cast alloy exhibited a lower wear rate as compared to the heat-treated alloy. The polarization curves in 3.5% NaCl show that the PEO coatings in all cases reduced the corrosion current density and shifted the corrosion potential toward positive values, thus indicating protective properties of the coatings. The corrosion rate of the as-cast and heat-treated Al-Zn-Mg-Ni-Fe alloys increased noticeably by about 3.7–5.7 times after PEO treatment. A relationship between the residual alloying elements Zn and Mg in the bulk of the PEO coatings and corrosion resistance was established. [ABSTRACT FROM AUTHOR]

Plasma electrolytic oxidation (PEO) is normally carried out under conditions with electrolyte cooling. However, the effect of the temperature of the electrolytes on the PEO behavior and properties of the resulting coatings is seldom investigated. In this study, PEO of pure Al was carried out in a dilute aluminate electrolyte with the electrolyte temperature being controlled under low (~10–30 °C), medium (~40–50 °C) and high (~70–80 °C) temperature ranges, respectively. The morphology, microstructure, composition and phase component of the coatings fabricated under the different temperature ranges were analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The corrosion resistances of the coatings were evaluated by electrochemical methods. The hardness of the coatings and substrate following the PEO treatment in the different electrolyte temperature ranges were also tested. It was found that a higher electrolyte temperature resulted in a higher growth rate and rougher coatings. Moreover, the α-Al2O3 content was reduced as the electrolyte temperature increased. The highest corrosion resistance was registered for the coating obtained under the lowest temperature range, whereas the corrosion resistance of the coating obtained under the highest temperature range was the worst. The higher growth rate under high electrolyte temperatures was associated with the increased kinetics of the PEO reactions. However, the temperature of the electrolyte should be controlled under a suitable range to ensure reasonable coating properties. [ABSTRACT FROM AUTHOR]

Despite the increasing interest in enhancing the electrochemical stability of Al alloys through protective coatings, the role of electron donor agents during coating formation remains poorly understood in terms of morphological control and anticorrosion properties in aqueous environments. In this context, 1H-Benzotriazole (BTA) was utilized as a proof of concept to regulate the in situ reactive integration of V2O5 into the alumina layer via the plasma electrolytic oxidation of a 6061 Al alloy. BTA played a crucial role in chemically incorporating V2O5 into the alumina coating by supplying electrons to VO3− ions, facilitating their reduction. The quantity of BTA added to the electrolyte was found to influence defect morphology and concurrently enhance the chemical incorporation of V2O5. Notably, corrosion measurements revealed that the less porous hybrid film formed with higher corrosion resistance was associated with the utilization of increased concentrations of BTA. These findings highlight the potential of BTA in modifying the structure and improving the ability of alumina coatings to resist corrosion, enabling advanced applications in protecting Al alloys from corrosion. [ABSTRACT FROM AUTHOR]

The present study investigates the influence of organic acids, added to the electrolytic solution, on the structure, morphology, and corrosion behaviour of plasma electrolytic oxidation (PEO) coatings produced on titanium grade 2. Particular attention is paid to the role of functional groups in the modification of the oxide's properties. For this reason, all three selected acids, namely glutaric, glutamic, and tartaric acid, display two carboxylic groups, thus they interact with the substrate material mainly through –COO− adsorption. However, glutamic acid also has an amine group, while tartaric acid has two hydroxyl groups. The presence of such additional functional groups is found to impact the formation of the PEO coatings. According to scanning electron microscopy (SEM) analyses, the number of defects and their dimension increase with an increasing number of active groups present in the organic molecules. Then, when glutaric acid with only two carboxyl groups, is employed as an additive, smaller pores are produced. The dimension of defects increases when glutamic and tartaric acid are used. X-ray diffraction (XRD) testing demonstrates that rutile and anatase are present in all the coatings and that when using tartaric acid, a relatively high level of amorphism is reached. The electrochemical and corrosion behaviours are evaluated by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) performed in a heated sulphuric acid solution. It is found that all types of coatings provide protection against corrosion, with oxides produced using glutamic acid showing the lowest corrosion current density (0.58 mA·m−2) and low corrosion rate (1.02 μm·y−1). [ABSTRACT FROM AUTHOR]

In this article, the process of creating calcium phosphate coatings through plasma electrolytic oxidation was investigated. Calcium phosphate coatings were deposited onto titanium substrates fabricated via the selective laser melting (SLM) method. The correlation between the characteristics of the coating and the applied voltage (200, 250, and 300 V) of PEO was studied. The surface morphology analysis indicates that an increase in applied voltage results in a larger pore size. It was discovered that, when a voltage of 300 V was applied, a layer of hydroxyapatite formed. However, at 300 V, the coating cracked, producing a significantly rough surface. Our analysis of the elemental composition of sample cross sections indicates the presence of TiO2 layers that are enriched with calcium (Ca) and phosphorus (P). The coefficient of friction and wear rate are primarily influenced by the morphology, pore size, and density of the titanium dioxide layer. Furthermore, a rise in the quantity of the beta phase of the titanium on the surface can be noticed as the applied voltage increases. As a result, it also affects the mechanical and tribological characteristics of the coating. The sample treated to a voltage of 250 V demonstrates a higher resistance to wear and a lower elastic modulus in comparison to the other two coatings. [ABSTRACT FROM AUTHOR]

Ceramic protective coatings, primarily composed of spinel (MgAl2O4), magnesia (MgO), and trimagnesium phosphate (Mg3(PO4)2), were produced on magnesium AZ63 alloy through Plasma Electrolytic Oxidation (PEO) in mixed sodium phosphate/aluminate electrolytes with varying aluminate concentrations and constant processing time. The morpho-structural and compositional characteristics of the coatings were studied using X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Their functional mechanical and anti-corrosive properties were assessed through tribological testing, electrochemical impedance spectroscopy, and potentiodynamic bias tests. The findings indicated that the samples processed through PEO exhibited significantly enhanced properties compared to the AZ63 magnesium alloy. The best tribological properties were observed for the lowest aluminate concentration. Optimum corrosion resistance properties were obtained for coatings produced in a mixed electrolyte of 10 g/L sodium phosphate and 20 g/L sodium aluminate. [ABSTRACT FROM AUTHOR]

Electrolyzing water is an effective and feasible technology to achieve a large-scale hydrogen production in industry. However, it is still challenging to develop an efficient approach to fabricate a superior and stable hydrogen evolution reaction (HER) electrodes with low cost and outstanding catalytic efficiency. This work presents an innovative surface modification technique of plasma electrolytic oxidation (PEO) to fabricate superior MoN based coating electrodes. By simply introducing Na 2 MoO 4 and NiAc 2 into the electrolyte, a novel MoTiN and NiMoTiN coatings were successfully achieved on the surface of a titanium substrate by PEO and annealing treatments, which exhibits excellent mechanical adhesion and platinum-like catalytic properties. Importantly, it has been demonstrated that the newly formed MoTiN solid solution combined by active Mo 2 N and conductive TiN can contribute the superior catalytic activity and the subsequent Ni doping can effectively stabilize the structure and activity of MoTiN. Under the alkaline environment of 1 M KOH, the MoTiN and NiMoTiN coated electrodes require only 126 and 121 mV overpotential, respectively, to achieve a current density of 10 mA cm−2. Additionally, under the same test conditions, NiMoTiN can operate stably for over 24 h, demonstrating excellent HER catalytic activity and stability. This work provides new insights into the preparation of HER electrodes with superior mechanical properties and excellent catalytic performance towards industrial hydrogen production. [Display omitted] • Plasma electrolytic oxidation method is proposed to prepare coating electrodes. • Ni doping could enhance the catalytic activity and stability of MoTiN. • MoTiN and NiMoTiN coatings exhibit outstanding adhesion and catalytic activity. [ABSTRACT FROM AUTHOR]

Paired redox‐neutral electrolysis offers an attractive green platform for organic synthesis by avoiding sacrificial oxidants and reductants. Carboxylates are non‐toxic, stable, inexpensive, and widely available, making them ideal nucleophiles for C−C cross‐coupling reactions. Here, we report the electro/Ni dual‐catalyzed redox‐neutral decarboxylative C(sp3)−C(sp2) cross‐coupling reactions of pristine carboxylates with aryl bromides. At a cathode, a NiII(Ar)(Br) intermediate is formed through the activation of Ar−Br bond by a NiI‐bipyridine catalyst and subsequent reduction. At an anode, the carboxylates, including amino acid, benzyl carboxylic acid, and 2‐phenoxy propionic acid, undergo oxidative decarboxylation to form carbon‐based free radicals. The combination of NiII(Ar)(Br) intermediate and carbon radical results in the formation of C(sp3)−C(sp2) cross‐coupling products. The adaptation of this electrosynthesis method to flow synthesis and valuable molecule synthesis was demonstrated. The reaction mechanism was systematically studied through electrochemical voltammetry and density functional theory (DFT) computational studies. The relationships between the electrochemical properties of carboxylates and the reaction selectivity were revealed. The electro/Ni dual‐catalyzed cross‐coupling reactions described herein expand the chemical space of paired electrochemical C(sp3)−C(sp2) cross‐coupling and represent a promising method for the construction of the C(sp3)−C(sp2) bonds because of the ubiquitous carboxylate nucleophiles and the innate scalability and flexibility of electrochemical flow‐synthesis technology. [ABSTRACT FROM AUTHOR]

Nickel‐based catalysts are recognized as a promising alternative to platinum‐based catalysts for the alkaline hydrogen oxidation reaction (HOR) yet suffer from poor stability and relatively low activity. Herein, a nitrogen ligand‐assisted approach is reported to encapsulate nickel‐copper nanoparticles within few carbon layers, and by modulating the core and shell components/structure, the charge distribution in the nanostructures can be finely regulated. The optimized Ni93Cu7@NC catalyst exhibits outstanding HOR activity with an intrinsic activity of 61.0 µA cm−2 and excellent stability, which is among the most advanced Ni‐based HOR catalysts. Notably, an alkaline exchange membrane fuel cell utilizing this catalyst achieves a peak power density of 381 mW cm−2 and maintains stability at 100 mA cm−2 for over 24 h. Experimental and theoretical investigations unveil that the electron re‐distribution at the interface of NiCu core and nitrogen‐doped carbon reduces the electron occupancy in Ni 4s‐H 1s bonding orbitals and Ni 3dz2/yz‐O 2p antibonding orbitals, leading to a weakened hydrogen binding energy and enhance hydroxide binding energy. Consequently, the limiting energy for the HOR is reduced following a bifunctional mechanism on the Ni93Cu7@NC. This work provides a core‐shell co‐modulation strategy to accurately regulate the electronic structure of transition metals to design robust catalysts. [ABSTRACT FROM AUTHOR]

A comprehensive study was conducted on the synthesis of FeMnTi monolithic catalysts using plasma electrolytic oxidation (PEO) process combined with hydrothermal method followed by depositing active nanostructures. As synthesized catalysts were characterized using a series of techniques for morphology, structure and surface chemical state investigations. Meanwhile, the CO light‐off curves demonstrate that they possess excellent low‐temperature catalytic performance compared with TiO2 based single transition oxides. Specifically, FeMnTi(0.10, 4) can achieve 100 % conversion at 201 °C, which is due to the homogeneous elements distribution, large surface area and high surface activity. The supersaturation of the deposited solution and deposition time determine the growth of MnOx and the FeMnTi(0.10, 4) has the most suitable Fe/Mn atom ratio of 2.5. Furthermore, the electron transfer between Fe (Fe2+ and Fe3+) and Mn (Mn2+, Mn3+ and Mn4+) ensures the excellent redox properties. The synthetic strategy proposed in this work has general applicability for synthesizing multiple transition oxides monolithic catalysts not only for CO oxidation. [ABSTRACT FROM AUTHOR]

Herein, a new method has been developed for the synthesis of various α‐hydroxyacetophenones via an electro‐oxidation process. It involves electrocatalytic hydroxylation via debromination of C(sp3)−Br bond. Here, simultaneous breaking of carbon‐bromine (C−Br) bond and formation of a new carbon‐oxygen (C−O) bond has been achieved through electrolysis of H2O using binary mixture of water and DMSO. The protocol features easy performance, oxidant and base‐free mild conditions and short reaction time. [ABSTRACT FROM AUTHOR]

To improve the complexity and low catalytic performance and reduce the high cost of the traditional electrode preparation process for the sodium borohydride electro-oxidation reaction (BOR), in this work, a self-supported and efficient electrode material grown on nickel foam (CoNi/Co3O4/NF) was successfully designed using a simple hydrothermal synthesis method accompanied by the electrodeposition process. Benefiting from the three-dimensional nanoarray structure of CoNi/Co3O4/NF and the uniform distribution of Co and Ni modulating active sites by electrodeposition, the catalytic activity towards NaBH4 exhibits high efficiency. CoNi/Co3O4 exhibits excellent catalytic performance (up to 2157 mA cm−2 in 2 mol L−1 NaOH and 0.3 mol L−1 NaBH4), a high electrochemically active surface area (62.5 cm−2), and a low activation energy (15.56 kJ mol−1). The CoNi/Co3O4/NF electrode was further investigated on a direct sodium borohydride–hydrogen peroxide fuel cell (DBHPFC), which exhibited a maximum power density of 108.5 mW cm−2 and excellent stability. The excellent performance is mainly due to its unique nanoarray structure and electrodeposition distribution of Co and Ni active sites, which increases the electrochemical surface area and enhances the contact between the electrode and the electrolyte. [ABSTRACT FROM AUTHOR]

Long-term electrolyses of glucose in a potassium carbonate (K2CO3) aqueous electrolyte have been performed on graphite felt electrodes with TEMPO as a homogeneous catalyst. The influences of the operating conditions (initial concentrations of glucose, TEMPO, and K2CO3 along with applied anode potential) on the conversion, selectivity toward gluconate/glucarate, and faradaic efficiency were assessed first. Then, optimizations of the conversion, selectivity, and faradaic efficiency were performed using design of experiments based on the L9 (34) Taguchi table, which resulted in 84% selectivity toward gluconate with 71% faradaic efficiency for up to 79% glucose conversion. Side products such as glucaric acid were also obtained when the applied potential exceeded 1.5 V vs. reversible hydrogen electrode. [ABSTRACT FROM AUTHOR]

In this study, to reactivate the oxide film and to secure biocompatibility, plasma electrolytic oxidation (PEO) treatment and hydroxyapatite (HA) deposition via mechanical coating (MC) processes were investigated. This experimental approach involved subjecting the Ti–6Al–4V alloy specimens to PEO treatment, followed by MC with HA powder for different hours as HA has the potential to increase bioactivity and surface characteristics due to its chemical composition and structural properties similar to natural bone. Therefore, the study aimed to examine the effects of MC with HA powder for 0, 1, 3, 5, 7, and 9 h on PEO-coated Ti–6Al–4V alloy discs for analyzing the surface characterization, phase analysis, surface roughness, wettability, adhesion strength, hardness, corrosion behavior, and cell proliferation properties for dental implant use. The findings demonstrate that prolonged HA milling enhances the substrate's mechanical strength, corrosion resistance, and adhesion properties. The presence of prominent anatase and HA peaks, particularly in the 5 MC-PEO, 7MC-PEO, and 9 MC-PEO samples, validates the synergistic impact of the PEO oxide layer and HA milling, resulting in outstanding corrosion resistance and biocompatibility. Cell culture analysis reveals a positive correlation between increased milling time and enhanced cell proliferation, particularly towards small-sized HA particles. [Display omitted] [ABSTRACT FROM AUTHOR]

To better understand the process and mechanism of lignin structural changes and relative product formation during PbO2 anode electrolysis, a Ti/Sb−SnO2/PbO2 composite electrode has been prepared and utilized for the alkaline electrolytic oxidation of both alkali lignin (AL) and bagasse organosolv lignin (OL). By combining electrochemical measurements, in‐situ FTIR, 2D‐HSQC NMR, and product distribution analysis, we not only investigate the impact of influence factors on the process of lignin depolymerization, but also reveal the depolymerization mechanism from the whole process of lignin structural changes in details. Under certain electrolysis conditions, the highest vanillin yield, 10.1 mg g−1, has been obtained through the electrolysis of alkali lignin, whereas the highest syringaldehyde yield of 4.0 mg g−1 has been achieved during the electrolysis of organic solvent lignin. In particular, AL mainly performs depolymerization through the selective cleavage C−C bonds to produce a series of G unit monomer products of vanillin, acetovanillone, and vanillic acid. By contrast, the depolymerization of OL shows significant selectivity in H units. Particularly, the production of the major H unit monomer product of 4‐vinylphenol has been confirmed by IR spectroelectrochemical studies from the oxidation and decarboxylation of p‐coumaric acid unit. [ABSTRACT FROM AUTHOR]

Efficient electrocatalytic oxidation of furfural to maleic acid (MA) is highly attractive, but challenging. Designing robust and cost-effective catalysts is the key for application. Herein, a bimetallic oxide catalyst (MnCeOx) was constructed by pyrolyzing the corresponding metal--organic framework (MOF) precursor. It was found that the obtained MnCeOx exhibited superior catalytic performance for electro-oxidation of furfural to produce MA, and the MA yield could reach 67.4% at an applied potential of 1.7 V vs. Ag/AgCl. Systematic investigations revealed that the excellent performance of MnCeOx originated from its suitable ability of forming surface oxygen vacancies, which could enhance the furfural adsorption on the active interfacial region of MnCeOx, thereby leading to the high catalytic activity of MnCeOx. [ABSTRACT FROM AUTHOR]

Efficient electrocatalytic oxidation of furfural to maleic acid (MA) is highly attractive, but challenging. Designing robust and cost-effective catalysts is the key for application. Herein, a bimetallic oxide catalyst (MnCeOx) was constructed by pyrolyzing the corresponding metal--organic framework (MOF) precursor. It was found that the obtained MnCeOx exhibited superior catalytic performance for electro-oxidation of furfural to produce MA, and the MA yield could reach 67.4% at an applied potential of 1.7 V vs. Ag/AgCl. Systematic investigations revealed that the excellent performance of MnCeOx originated from its suitable ability of forming surface oxygen vacancies, which could enhance the furfural adsorption on the active interfacial region of MnCeOx, thereby leading to the high catalytic activity of MnCeOx. [ABSTRACT FROM AUTHOR]

Zinc (Zn) distinguishes itself as an excellent candidate for temporary orthopaedic implants due to its advantageous corrosion rate compared to other biodegradable metallic materials like Mg and Fe. The present research involved the fabrication of a porous, corrosion-resistant, and biocompatible plasma electrolytic oxidation (PEO) coating on a Zn–1Mg alloy. Bioactivity was imparted to the PEO coating by incorporating hydroxyapatite (HA) and silver-incorporated hydroxyapatite (SHA) nanoparticles into it by synergising the PEO process with electrophoretic deposition (EPD) in a single step. FESEM and EDS are utilised to confirm the porous PEO oxide layer formation and its sealing by HA and SHA particles in PEO-EPD coating. The coatings' phase composition, surface roughness, scratch resistance, and wettability were evaluated to assess their suitability for temporary implant applications. The coatings' wettability and roughness significantly improved compared to the untreated substrate, rendering it suitable for orthopaedic implant applications. The scratch resistance of the PEO coating was satisfactory and showed additional improvement in the thicker film with lower porosity, achieved through the combined PEO-EPD process. The electrochemical corrosion test in biological media revealed that the PEO coating enhanced the degradation resistance of Zn–1Mg, which was further enhanced by incorporating HA and SHA particles into the PEO coating. The in-vitro bioactivity test in simulated body fluid (SBF) and cytotoxicity test using L929 (Mouse fibroblast) cells proved that adding HA made the fabricated PEO coating biologically more favourable. Furthermore, the SHA-incorporated PEO coating is antibacterial against E. coli bacterial strains, enabling protection against post-implantation infections. • ZnO-HA ceramic composite coating developed on Zn–1Mg by PEO. • ZnO-HA coating showed 3 orders lower i corr compared to bare alloy. • Ceramic-composite coating proved to be bioactive and biocompatible. • Silver-incorporated coating exhibited the bactericidal property. [ABSTRACT FROM AUTHOR]

The surface topological features of bioimplants are among the key indicators for bone tissue replacement because they directly affect cell morphology, adhesion, proliferation, and differentiation. In this study, we investigated the physical, electrochemical, and biological responses of sandblasted titanium (SB-Ti) surfaces with pore geometries fabricated using a plasma electrolytic oxidation (PEO) process. The PEO treatment was conducted at an applied voltage of 280 V in a solution bath consisting of 0.15 mol L−1 calcium acetate monohydrate and 0.02 mol L−1 calcium glycerophosphate for 3 min. The surface chemistry, wettability, mechanical properties and corrosion behavior of PEO-treated sandblasted Ti implants using hydroxyapatite particles (PEO-SB-Ti) were improved with the distribution of calcium phosphorous porous oxide layers, and showed a homogeneous and hierarchically porous surface with clusters of nanopores in a bath containing calcium acetate monohydrate and calcium glycerophosphate. To demonstrate the efficacy of PEO-SB-Ti, we investigated whether the implant affects biological responses. The proposed PEO-SB-Ti were evaluated with the aim of obtaining a multifunctional bone replacement model that could efficiently induce osteogenic differentiation as well as antibacterial activities. These physical and biological responses suggest that the PEO-SB-Ti may have a great potential for use an artificial bone replacement compared to that of the controls. [ABSTRACT FROM AUTHOR]

Nitrogen-doped mesoporous carbon (N-MC) was prepared by pyrolysis of melamine-modified resorcinol-formaldehyde (RF) resin in different melamine molar ratios under N2 atmosphere at 900 °C. The resulting N-MC materials were used as a support of Pd nanoparticles (Pd/N-MC) and evaluated as catalyst for a formic acid electro-oxidation reaction (FAOR) by cyclic voltammetry. The physical-chemical characteristics of the N-MCs were evaluated by FTIR, XRD, SAXS, Raman, and BET techniques. The N-MC obtained from resins with higher melamine concentration resulted in carbon structure with higher graphitic crystallinity and morphology with deformed pores caused by inefficient self-assembly; furthermore, the N content, determined by elemental analysis, ranged from 1.2 to 3.3%. For Pd/N-MC catalysts, the TEM analysis showed better dispersion and narrow size distribution of Pd nanoparticles for the catalysts supported on N-MC, being the smallest for Pd/MC10. The electrochemical evaluation confirmed that the catalysts supported in N-MC with open-cylindrical pores and high N content exhibited higher electrochemical surface area (ECSA). In addition, the catalytic activity towards FAOR indicated higher current densities at lower potential values than Pd/MC. This study demonstrates that in-situ Nitrogen doping is a convenient methodology to obtain N carbon materials with well-tailored pores that promote better dispersion of metal nanoparticles, and support-catalyst interaction resulting in enhanced electrochemical properties. [ABSTRACT FROM AUTHOR]

The fast, accurate, and affordable determination of the anti-epileptic drug levetiracetam (LEV) is the need of time for human health. In this study, a novel electrochemical sensor platform was proposed for the cost-effective and sensitive determination of the levetiracetam based on molybdenum sulfide nano-flower-adorned pencil graphite electrode (MoS2/PGE). The nano-flowers of MoS2 were prepared by a cost-effective one-step facile hydrothermal method and the morphology of synthesized MoS2 micro-flowers was characterized via FESEM, XRD, and EDS techniques. The various electro-kinetics parameters like diffusion coefficient (Do =1.41 × 10−5 cm2 s−1), heterogeneous rate constant (Kh= 9.04 × 10−4 cm s−1), electron transfer coefficient (α = 0.66), the effective surface area of the fabricated electrode (A = 0.0767 cm2), and surface coverage (Γo = 2.98 × 10−11 mol cm−2) were evaluated for the oxidation of LEV at MoS2/PGE employing voltammetric techniques. The oxidative peak current in the optimized square wave stripping voltammetry varies linearly with LEV concentration within the range of 72.0 to 130.0 µM with detection limit (LOD) value of 14.20 µM. The proposed MoS2/PGE platform provides a sensitive, low cost and eco-friendly tool for the rapid detection of LEV in clinical samples. [ABSTRACT FROM AUTHOR]

This study presents an eco‐conscious approach to enhance the efficiency of the Suzuki–Miyaura cross‐coupling reaction. We first synthesized graphene oxide nanosheets using the Hummers method and then coated them to incorporate metallic copper on their surface. Following this, we conducted various analyses, including Fourier transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis, cyclic voltammetry (CV), and energy‐dispersive X‐ray spectroscopy (EDS) identification, to characterize these modified nanosheets. Subsequently, we utilized Cu‐modified graphene oxide nanosheets as cathode catalysts in an electro‐oxidation synthesis setup. To verify the effectiveness of this novel approach, we utilized bromobenzene and phenylboronic acid as model substrates to synthesize biphenyl compounds. The reaction yielded impressive product yields ranging from 87% to 93%. Operating under environmentally friendly conditions, this electro‐oxidation synthesis not only enhances selectivity but also significantly reduces the environmental impact of the reaction. Our findings highlight the potential of this green chemistry strategy, offering a promising avenue for sustainable and efficient organic synthesis, as evidenced by the successful coupling of bromobenzene and phenylboronic acid with consistently high yields. [ABSTRACT FROM AUTHOR]

A facile and reduced cost fabrication protocol was followed to have a series of nickel oxide nanospecies onto graphite support with introducing varied copper oxide wt.% values (NiCuO/T). The co‐precipitation of metallic hydroxide particles onto carbonaceous surfaces and their subsequent burning at 400°C were sufficient to prepare mixed transition metal oxides. Suitable analysis tools were exploited to fully characterize the obtained nanopowders using scanning electron microscopy, transmission electron microscopy, X‐ray diffraction spectroscopy, X‐ray photoelectron spectroscopy, and energy dispersive X‐ray analysis. Outstanding performances of the formed nanocatalysts for catalyzing ethanol electro‐oxidation reaction were measured especially in presence of 15 wt.% copper oxide content. The onset potential (Eonset) value of alcohol oxidation process was negatively shifted at dispersed NiO nanoparticles onto graphite after doping with copper oxide nanospecies. This promoted activity of prepared nanomaterials could be explained by their increased active sites when binary metallic oxides were incorporated. Electrochemical impedance spectroscopy studies demonstrated much lowered resistances in alkaline solution containing ethanol molecules to ascertain the enhanced behavior of NiCuO/T nanocatalysts. Moreover, their good stability attitude encouraged the application of doped nanomaterials with copper oxide for fuel cells application. [ABSTRACT FROM AUTHOR]

Studies on dissimilar materials joining have greatly increased, transitioning from temporary to permanent joining methods. The latter approach is more applicable due to the hybrid structure offering the best properties of the constituent materials, along with the development of new materials and manufacturing procedures. In this study, the AA2024-T3 alloy was treated with plasma electrolytic oxidation (PEO) and a thermoplastic composite/AA2024-T3 hybrid joint was manufactured using oxy-fuel welding (OFW). Morphological aspects, chemical compositions electrochemical and mechanical properties of hybrid composite joints were determined. The results indicated that the joint exhibits a uniform structure. The adhesion between the dissimilar materials reached a strength of 4.2 to 5.2 MPa, with cohesive bonding and without severe degradation of the thermoplastic matrix in some cases. It was observed that PEO treatment decreased the interface shear strength due to the high silicon content presence in the coating. The coatings effectively increased nobility and corrosion resistance, with corrosion rates ranging from 0.0087 to 0.018 mm/year. [ABSTRACT FROM AUTHOR]

• Ca/P antibacterial coatings with vancomycin were formed on Mg alloy. • Coatings improve corrosion properties of Mg alloy. • Coatings have superior antibacterial effect against both S. aureus. • Formed coatings do not have any cytotoxic effect according to MTT assay. • In vivo studies demonstrated that coatings do not have systemic toxicity. In this study, a calcium-phosphate coating was formed on a Mg–Mn–Ce alloy by the plasma electrolytic oxidation (PEO). The antibiotic vancomycin, widely used in the treatment of infections caused by Staphylococcus aureus (S. aureus), was impregnated into the coating. Samples with vancomycin showed high bactericidal activity against S. aureus. The mechanical and electrochemical properties of the formed coatings were studied, as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were performed. According to SEM, EDS, XRD and XPS data, coatings had a developed morphology and contained hydroxyapatite, which indicates high biocompatibility. The analysis of roughness of coatings without and with vancomycin did not reveal any differences, confirming the high roughness of the samples. During electrochemical tests, an increase in corrosion resistance by more than two times after the application of PEO coatings was revealed. According to the results of an in vivo study, after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin, no signs of inflammation were observed, while an inflammatory reaction developed in the area of implantation of bare alloy, followed by encapsulation. Antibiotic release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day 28. Throughout the experiment, no significant deviations in the condition and behavior of the animals were observed; clinical tests did not reveal a systemic toxic reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

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In this research, successive electro-oxidation (EO) process was utilized to eliminate some of the primary organic contaminants in effluent wastewater, specifically phenol and chemical oxygen demand (COD). The performance of the electro-oxidation process was studied by using two graphite electrodes as anodes and three stainless steel electrodes as cathodes, which is a new strategy in this field. Taguchi method has been used to design experiments to approach the best experimental conditions for phenol and COD removal as significant responses. The best operating conditions that resulted in the maximum reduction of phenol and COD were current density (CD=25 mA/cm²), pH=4, support electrolyte (NaCl=2g/l), the distance between electrodes (Dist.=5mm), and time of 60 minutes. At these operating conditions, phenol and COD removal were 99.27% and 99.96%, respectively. This work provides important insights into a novel water and wastewater treatment method with a detailed analysis of the results. [ABSTRACT FROM AUTHOR]

In this work, UiO-66-NH2/GO nanocomposite was prepared using a simple solvothermal technique, and its structure and morphology were characterized using field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). An enhanced electrochemical sensor for the detection of epirubicin (EP) was proposed, which utilized a UiO-66-NH2/GO nanocomposite-modified screen-printed graphite electrode (UiO-66-NH2/GO/SPGE). The prepared UiO-66-NH2/GO nanocomposite improved the electrochemical performance of the SPGE towards the redox reaction of EP. Under optimized experimental conditions, this sensor demonstrates a remarkable limit of detection (LOD) of 0.003 µM and a linear dynamic range from 0.008 to 200.0 µM, providing a highly capable platform for sensing EP. Furthermore, the simultaneous electro-catalytic oxidation of EP and topotecan (TP) was investigated at the UiO-66-NH2/GO/SPGE surface utilizing differential pulse voltammetry (DPV). DPV measurements revealed the presence of two distinct oxidation peaks of EP and TP, with a peak potential separation of 200 mV. Finally, the UiO-66-NH2/GO/SPGE sensor was successfully utilized for the quantitative analysis of EP and TP in pharmaceutical injection, yielding highly satisfactory results. [ABSTRACT FROM AUTHOR]

The ethanol oxidation reaction (EOR) is crucial in direct alcohol fuel cells and chemical production. However, the electro-oxidation of ethanol molecules to produce acetaldehyde and carbon monoxide can poison the active sites of nanocatalysts, resulting in reduced performance and posing challenges in achieving high activity and selectivity for ethanol oxidation. In this study, we employed a dynamic seed-mediated method to precisely modify highly dispersed Ru sites onto well-defined Pd nanocrystals. The oxyphilic Ru sites serve as "OH valves", regulating water dissociation, while the surrounding Pd atomic arrangements control electronic states for the oxidation dehydrogenation of carbonaceous intermediates. Specifically, Ru0.040@Pd nanocubes (Ru:Pd = 0.04 at.%), featuring (100) facets in Ru-Pd4 configurations, demonstrate an outstanding mass activity of 6.53 A ⋅ mg Pd − 1 in EOR under alkaline conditions, which is 6.05 times higher than that of the commercial Pd/C catalyst (1.08 A ⋅ mg Pd − 1 ). Through in-situ experiments and theoretical investigations, we elucidate that the hydrophilic Ru atoms significantly promote the dynamic evolution of H2O dissociation into OHads species, while the electron redistribution from Ru to adjacent Pd concurrently adjusts the selective oxidation of C2 intermediates. This host–guest interaction accelerates the subsequent oxidation of carbonaceous intermediates (CH3COads) to acetate, while preventing the formation of toxic ⋆CHx and ⋆CO species, which constitutes the rate-determining step. [ABSTRACT FROM AUTHOR]

With the rapid development of the global aerospace industry, higher requirements have been placed on the comprehensive performance of structural materials for aviation. Among them, titanium alloys are widely used in the design of rocket engine casings, rocket nozzle conduits and artificial satellite casings because of their high strength, good corrosion resistance and high heat resistance. However, the surface of titanium alloy has poor wear resistance, which makes it difficult to adapt to its practical use in the aviation environment, especially in high-temperature and wide-temperature conditions. Researchers have found that the preparation of molybdenum disulfide solid lubrication coatings on the surface of titanium alloys can significantly improve this problem. This review summarizes the research progress of MoS2-based material coatings, which contains the design of MoS2-based coating components, and the preparation methods of MoS2-based coatings. Therefore, the unitary, binary, diversified and multilayer designs of molybdenum disulfide-based materials in coatings are discussed. In addition, the current preparation methods of MoS2-based materials are reviewed, focusing on the improvement of wear resistance of titanium surfaces by MoS2–Ti coatings as well as plasma electrolytic oxidation (PEO) technology. Finally, the advantages and disadvantages of the current research on molybdenum disulfide-based materials are summarized, aiming to provide some references for the practical application of titanium alloys in the aerospace field. [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cells (DEFCs) play an indispensable role in the cyclic utilization of carbon resources due to its high volumetric energy density, high efficiency, and environmental benign character. However, owing to the chemically stable carbon‐carbon (C─C) bond of ethanol, its incomplete electrooxidation at the anode severely inhibits the energy and power density output of DEFCs. The efficiency of C─C bond cleaving on the state‐of‐the‐art Pt or Pd catalysts is reported as low as 7.5%. Recently, tremendous efforts are devoted to this field, and some effective strategies are put forward to facilitate the cleavage of the C─C bond. It is the right time to summarize the major breakthroughs in ethanol electrooxidation reaction. In this review, some optimization strategies including constructing core–shell nanostructure with alloying effect, doping other metal atoms in Pt and Pd catalysts, engineering composite catalyst with interface synergism, introducing cascade catalytic sites, and so on, are systematically summarized. In addition, the catalytic mechanism as well as the correlations between the catalyst structure and catalytic efficiency are further discussed. Finally, the prevailing limitations and feasible improvement directions for ethanol electrooxidation are proposed. [ABSTRACT FROM AUTHOR]

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

Ionic crystal ceramics are known to be susceptible to brittle cracks along the intergranular due to the strong ionic bond forces. Accordingly, an outstanding toughened coating consisting of yttria-stabilized tetragonal zirconia (YSTZ) and MgO, with a reinforced heterointerface, has been successfully achieved through the plasma electrolytic oxidation process. The results demonstrate that the enhanced Zr/Y–O bond strength improves the interfacial strength of the ionic crystal, while the lattice distortion activates continuous dislocation pinning at the (101) YSTZ//(111) MgO semicoherent heterointerface effectively hinders crack propagation of the coating. With the YSTZ content approaching 65 %, the toughness (K IC) value surpasses that of PEO coating by 42 %. These findings not only elucidate the scientific foundation for the improved toughness of the YSTZ/MgO nanocoating but also provide valuable insights into design strategies for improving ceramic toughness. [ABSTRACT FROM AUTHOR]