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Lithium‐metal anodes (LMAs) are the ultimate choice for realizing high‐energy‐density batteries; however, its use is hindered by problematic Li growth in the form of dendrites. To alleviate dendritic Li growth, the preparation of LMAs with a lithiophilic current collector (CC) is effective; however, applying a lithiophilic CC to LMAs is still challenging due to the manufacturing complexity involved in the separate lithiophilic treatment and lithiation processes. Herein, a facile one‐pot LMA fabrication method by utilizing thiourea (TU) as a precursor is proposed. A lithiophilic Cu2S layer is formed on Cu foam (CF) by the in situ electrochemical oxidation of TU (CuxSCF), and the lithiation of CC is performed via subsequent Li electrodeposition (Li@CuxSCF). The Cu2S on CuxSCF can lead to uniform Li deposition by providing lithiophilic sites, and it is converted to form ionic‐conductive Li2S‐rich solid electrolyte interphase layer. Resultantly, CuxSCF significantly enhances the cycling performance of LMAs compared to CF. Specifically, a LiFePO4/Li@CuxSCF full‐cell lithium‐metal battery (LMB) with a low n/p ratio (1.6) exhibits capacity retention of 95.6% at 0.5 C (220 cycles) and can maintain 85.0% of initial capacity (425 cycles, n/p = 4) at 2.0 C. LMBs with LiNi0.6Co0.2Mn0.2 and LiNi0.8Co0.1Mn0.1 also exhibit improved electrochemical performance. [ABSTRACT FROM AUTHOR]

The development and application of rechargeable aqueous zinc‐ion batteries are seriously hindered by the problems of corrosion and dendrite growth on Zn metal anodes. Herein, a polyporous 3D zinc framework coupled with a zincophilic ZnSe overlayer (3D‐Zn@ZnSe) is synchronously obtained by one‐step electrochemical scanning, which precisely repairs intrinsic defects of the Zn foil surface and remodels the electrolyte/anode interface. The 3D‐Zn host formed by the pioneering electro‐oxidation significantly reduces the local current densities and facilitates adapting to the volume change during the plating/stripping. Meanwhile, the ZnSe overlayer obtained by electro‐deposition restrains the side reactions and promotes efficient desolvation, resulting in the acceleration of the deposition kinetics of Zn2+ on the zinc anode. As a result, the anodes present an enhanced cycling stability of zinc plating/stripping for over 2000 h with low overpotential, and the assembled 3D‐Zn@ZnSe||V2O5 cell retains 90.63% of its original capacity after 8500 cycles. The one‐step fabrication of polyporous interfaces with a zincophilic overlayer presents a promising strategy on improving the stability and reversibility of zinc anode for zinc‐based batteries. [ABSTRACT FROM AUTHOR]

This paper discusses a systematic study of Congo red dye removal by electrocoagulation process with an aluminium electrode pair. The statistical modelling technique, response surface methodology is used for the design of experiments. The various operating parameters chosen are reaction time (10–60 min), initial dye concentration (20–80 mg/L), pH of the solution (5–11) and the applied voltage (5–20 V) with removal efficiency and energy consumption as responses. The results show the leading role of various parameters on maximizing removal efficiency and minimizing energy consumption, and the optimum conditions obtained are initial dye concentration of 65 mg/L, solution pH of 9.5, the reaction time of 25.08 min and an applied voltage of 8.75 V. According to the experimental results, the maximum removal efficiency obtained is 89.344% with an energy consumption of 9.4589 W h. The analysis of variance (ANOVA) results in a regression coefficient of 0.9701 and 0.9993 for removal efficiency and energy consumption, respectively, and it indicates only 0.29% and 0.01% chance of deviation for the developed model from the actual operating conditions. The various characterization results affirm the removal of dye with in situ formed coagulants of aluminium by adsorption and charge neutralization mechanism. The kinetic study reveals that the pseudo-second-order model is the best-fitted model for the removal of Congo red dye. [ABSTRACT FROM AUTHOR]

Synthetic textile dyes have considerable molecular complexity, which makes these compounds highly stable and resistant to different types of treatments. Azo dyes represent the most commonly used group of dyes in textile industry. Azo dye contaminants in wastewater are recalcitrant, and microbiological treatments and oxidative processes have been widely studied to remedy this problem. These treatments can transform recalcitrant substances into substances with low toxicity. Therefore, microbiological and electrochemical/microbiological discoloration treatments were performed with the azo textile dye Acid Blue 161 in aqueous solution. The microbiological discoloration treatments were carried out using the filamentous fungus Aspergillus terreus and the yeast Saccharomyces cerevisiae. Discoloration treatments were performed with and without electrochemical pretreatment. The acute toxicity of the solutions was analyzed before and after the treatments using a vegetable test system (Lactuca sativa seeds). Adsorption treatment with white clay was performed to remove intermediate metabolites with high toxicological potential. At the end, all treatments tested were effective at discoloring the Acid Blue 161 dye solution. Moreover, the systems composed of the fungus A. terreus were more efficient and exhibited lower acute toxicity to L. sativa seeds at the end of 288 h of exposure to fungal biomass before and after adsorption treatment with white clay. [ABSTRACT FROM AUTHOR]

One of the most important challenges, for scaling up a photocatalytic system for VOCs abatement to full-scale, is the design of a suitable photocatalyst support. The support has to firmly immobilize the photocatalyst, without using an organic adhesive, and should also withstand relatively high mechanical stresses. Metals may be effectively implemented as a support material, after a corrugation of the surface with electrochemical treatments. In the present work, we treated stainless steel and aluminum supports, evaluating the surface modifications due to the electrochemical treatments, with scanning electron microscopy (SEM) and confocal microscopy. Five samples showing the highest degree of restructuring were selected and spray coated with P25, a TiO 2 photocatalyst, evaluating the mechanical stability of the coating with a standard tape test method. One particular stainless steel sample presented a superior surface restructuring and coating stability. The photocatalytic activity of this sample, evaluated measuring the complete oxidation of acetaldehyde, was tested for 15 h, and compared with sample of TiO 2 -P25 on a ceramic support. The stainless steel exhibited a constant performance after an initial stabilization period. The stainless steel sample showed a slightly higher activity, due to the surface restructuring, increasing the irradiated area available for the coated photocatalyst. [ABSTRACT FROM AUTHOR]

Three carbon materials from a varied origin, composition and porosity have been used as cost-effective cathodes in different electrochemical advanced oxidation processes (i.e. anodic oxidation (AO) and electro-Fenton (EF) in homogeneous and heterogeneous catalysis modalities) for the degradation of an antibiotic (e.g., metronidazole). In general, the efficiency towards the pollutant degradation increased as: AO < homogeneous EF < heterogeneous EF. The heterogeneous EF approach with iron pre-loaded in the carbon cathode outperformed the homogenous EF counterpart, despite a lower amount of iron. Reusability tests showed that iron-containing cathodes prepared from samples CQ (carbon obtained upon steam activation) and CB (carbon prepared by H 3 PO 4 activation of biomass) were stable over at least three consecutive cycles. The best results were attained for cathode prepared with carbon CQ modified with iron, yielding over 97% removal of metronidazole after 150 min in all three reuses. Such better performance is related to the favorable adsorption of the pollutant on carbon CQ, thereby favoring the close contact between the generated oxidant species and the target antibiotic. The cathode based on carbon CQ was tested for the degradation of another recalcitrant antibiotic (sulfamethoxazole) in a real wastewater treatment plant effluent by means of a heterogeneous EF treatment, showing good degradation performance. [Display omitted] • Cost-effective carbon-based cathodes were elaborated from varied carbons. • Cathodes were tested for antibiotics removal in anodic oxidation and electro-Fenton. • Heterogeneous electro-Fenton (Fe-loaded cathodes) showed the best performance. • Degradation of metronidazole and sulfamethoxazole from synthetic and real waters. • Carboxylic acids and nitrates indicated a partial mineralization of the antibiotics. [ABSTRACT FROM AUTHOR]

An anodic photo-galvanostatic treatment at low current density (1μA·cm−2) is carried out on n-InP semiconductor in liquid ammonia (223K). The gradual chemical evolution of the surface is studied as a function of the anodic charge. Proof and reproducibility of the chemical transformation of the surface are clearly evidenced by X-ray photoelectron spectroscopy (XPS) analyses. Like by cyclic voltammetry, the perfect coverage of the InP surface by a thin phosphazene like film is also revealed by XPS data. However, a low anodic charge (≈0.5mC·cm−2) is required by photo-galvanostatic treatment while a higher anodic charge (≈7mC·cm−2) is involved by cyclic voltammetry. The excess of charge could be related to ammonia oxidation during the formation of the passivating film. This result proves the electrochemical oxidation of the solvent as a determinant step of the mechanism film formation. [ABSTRACT FROM AUTHOR]

In this research work, the effect of various independent operating variables on the removal of malathion pesticide by electrocoagulation (EC) process was evaluated by single variable multivariable optimization. The various operating variables selected were reaction time (40–75 min), pH (6−9), applied voltage (8–20 V), and amount of electrolyte (8–20 ml). The effect of aluminium and iron electrode on the removal efficiency were compared and aluminium was found to be better performed, further RSM studies were carried out with this electrode. The optimum operational conditions were achieved as reaction time of 75 min, solution pH of 7.5, applied voltage of 15 V and the electrolyte addition of 15 ml. A removal efficiency of 85% was obtained at an energy consumption of kWh. by incorporating the interaction effects of different optimized variables. In this paper, the facts associated with the removal mechanism and the operational cost analyses were performed. The reaction behaviour has been discussed through mini reaction pathways and results were supported by SEM, EDAX and FTIR characterizations. End products of the EC process are the dissociated pesticide with metal hydroxide particles. This study also discusses the disposal of solid sludge with economic and environmental benefits used as admixture in the stabilization of expansive soils. The sludge fused soil properties were improved when compared to the plain soil properties and the classification of soil were changed from moderate to stiff soil. This indicates the possible use of sludge as stabilizing agent subsequently and it can address the disposal and environment concern related to the end products of EC process in economic way.Effect of this soil on the ground water pollution was also investigated. [Display omitted] • Comparison of the performance of aluminium and iron electrodes for the pesticide removal through EC process has been done. • Aluminium electrodes were proved to achieve higher removal efficiency due to its enmeshment in iron oxides and hydroxides. • The interactive effects of various operational variables on the performance parameters have been better explained using the statistical tool(RSM). • Characterization of the sludge at the optimized conditions was done and the major possible removal mechanism was suggested. • The produced sludge disposal was done in an eco-friendly manner. [ABSTRACT FROM AUTHOR]

Landfill leachate is a type of complex organic wastewater, which can easily cause serious negative impacts on the human health and ecological environment if disposed improperly. Electrochemical technology provides an efficient approach to effectively reduce the pollutants in landfill leachate. In this review, the electrochemical standalone processes (electrochemical oxidation, electrochemical reduction, electro-coagulation, electro-Fenton process, three-dimensional electrode process, and ion exchange membrane electrochemical process) and the electrochemical integrated processes (electrochemical-advanced oxidation process (AOP) and biological electrochemical process) for landfill leachate treatment are summarized, which include the performance, mechanism, application, existing problems, and improvement schemes such as cost-effectiveness. The main objective of this review is to help researchers understand the characteristics of electrochemical treatment of landfill leachate and to provide a useful reference for the design of the process and reactor for the harmless treatment of landfill leachate. Unlabelled Image • Electrochemical processes for landfill leachate treatment • Advantages and shortcomings of electrochemical processes • Improvement schemes of electrochemical processes • Future research needs on landfill leachate electrochemical treatment [ABSTRACT FROM AUTHOR]

Abstract: In this work, the effect of electrochemical oxidation treatments of activated carbon fibers (ACFs) was studied in heavy metal adsorption behaviors. As a result, the acidic or basic anodic treatment led to increases of Cr(VI), Cu(II), and Ni(II) adsorptions, which could be attributed to the oxygen-containing functional groups of the ACF surfaces. [Copyright &y& Elsevier]

This work evaluated the degradation of the Acid Blue 161 and Procion Red MX-5B dyes in a binary solution by the filamentous fungus Aspergillus terreus and the yeast Saccharomyces cerevisiae in systems with and without electrochemical oxidation as the pretreatment process. UV–Vis spectrophotometry, high-performance liquid chromatography with (HPLC), Fourier transform infrared (FT-IR) spectroscopy and Salmonella/ microsome assay (Ames test) were applied towards the degradation analysis of the dyes. Adsorption tests with white clay immobilized on alginate were also conducted after the discoloration treatments to remove intermediate metabolites formed during the degradation of the dye molecules. The discoloration treatments led to the complete color removal of the solutions in all the systems tested. The clay demonstrated affinity for the metabolites formed after discoloration treatments, the removal rates were variable, but the all systems has proved efficient. The Salmonella /microsome assay (Ames test) with strains TA98 and TA100 in the absence and presence of exogenous metabolism (S9 microsomal system, Moltox) revealed that the initial molecules and by-products of the metabolism of the dyes were direct mutagens. The electrochemical/ A. terreus /clay system was able to discolor the solutions and transform the direct mutagens into non-mutagenic compounds in addition to reducing the mutagenic potency of the pro-mutagens to the Salmonella strain TA100/S9, which demonstrates the high efficiency of this system with regard to discoloring and degrading azo dye molecules and their by-products. Therefore, this study showed that although not having standard treatment system for this type of pollutant, the combination of treatments can be considered promising. The use of electrochemical oxidation along with microbiological treatment may lead to the degradation and mineralization of these compounds, reducing or eliminating the environmental impact caused by the improper disposal of these dyes in aquatic environments. Image 1 • Discoloration treatments transformed mutagenic compounds into non-mutagenic compounds. • Treatment with clay can remove toxic metabolites originating from dyes degradation. • All the tested treatment systems efficiently removed color from the dyes solutions. [ABSTRACT FROM AUTHOR]

The room temperature sodium sulfur battery (RT‐NaS) has attracted considerable attention as a next‐generation energy storage system due to its low cost and high specific energy and the abundance of sodium and sulfur. However, the sulfur‐based cathode in RT‐NaS always undergoes dissolution of polysulfides during the cycle, which limits the utilization of active material and the stability of the RT‐NaS. In this study, the authors report an economical and simple method to suppress the dissolution of polysulfides by forming an artificial protective solid electrolyte interphase (SEI) on the cathode surface using an in situ electrochemical treatment with a fluoroethylene carbonate (FEC) electrolyte additive. The artificially formed SEI has a thickness of ≈20 nm and contains fluoride anions that improve electrical conductivity and mechanical stability. The RT‐NaS full cell with the sulfur–carbon cathode and protective SEI exhibits a 0.1 VNa+/Na lower electrochemical polarization for desodiation, and SEI and electrical resistances that are 23% and 45% lower, respectively, than those of untreated NaS. These improvements lead to a capacity increase of ≈120% (270 to 590 mAh g−1 at the 50th cycle) and a high Coloumbic efficiency of 99.5% in the high‐rate cyclability test of the 2 C rate over 200 cycles. A new facile method to prevent the shuttle effect in an RT‐NaS battery, that is artificially forming the protective solid electrolyte interphase (SEI) on a sulfur‐carbon composite cathode via in situ electrochemical method, is proposed. The RT‐NaS with in situ treated sulfur‐carbon cathode shows more than 200% higher capacity than untreated one, and an excellent long‐term high‐rate performance. [ABSTRACT FROM AUTHOR]