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A novel approach is proposed for combining phosphor materials with triboelectric nanogenerators (TENGs) for mechanical energy harvesting and illumination applications. For this purpose, strongly reddish‐orange‐emitting Ba0.5Sr0.5Nb2O6:0.25 mol Eu3+ (BSNb:0.25Eu) phosphor materials are synthesized. The photoluminescence properties of the synthesized BSNb:0.25Eu are analyzed. The synthesized BSNb:0.25Eu is utilized as a dielectric filler inside a polydimethylsiloxane polymeric film due to its high dielectric properties to improve the overall dielectric properties of the composite film (CF). TENG devices are fabricated using phosphor‐loaded CFs as the tribonegative layer, transparent polyvinyl alcohol as the tribopositive layer, and aluminum as the conductive electrode. All the TENGs operate in a contact‐separation mode, and the highest electrical output is attained by optimizing the phosphor filler concentration in the CF. The optimized TENG exhibits excellent stability in long‐term operational tests, under varying harsh ambient temperatures. Indium tin oxide sputtered on both triboelectric films as an electrode and combined with a transparent hard substrate to obtain a fully transparent TENG. A self‐illuminating TENG (SI‐TENG) is fabricated by integrating near‐ultraviolet light‐emitting diodes between two identical TENGs. The SI‐TENG can harvest the mechanical energy available in the surrounding environment and illuminate it as a light source. Additionally, the proposed phosphor‐loaded polymer films can be employed for optical thermometry and mechanical energy harvesting via SI‐TENG on a large scale. [ABSTRACT FROM AUTHOR]

One‐dimensional scanning optical beam‐induced current (OBIC) measurements have been carried out on polymer bulk heterojunction (BHJ) photovoltaic cells with a planar, or lateral configuration. The planar P3HT:PCBM cells have parallel aluminum or gold electrodes that are 390 to 560 micrometers apart. When a focused laser beam is scanned across the electrode gap, photocurrent or photovoltage is recorded as a function of beam position along with the transmission of the excitation beam. Despite the large electrode gap size, cells with symmetric Al/Al electrodes exhibit significant photocurrent and photovoltage which are the highest at the electrode interfaces and null at the cell center. The OBIC in these large planar polymer BHJ cells is attributed to the metal/BHJ blend Schottky junction. The larger Schottky barrier of the Al/BHJ junction gives rise to a stronger OBIC response than the Au/BHJ junction. The photocurrent and photovoltage always have opposite signs and are antisymmetric about the cell center. In asymmetric Al/Au cells, the electrode work function difference contributes an additional built‐in field/potential drop and significantly modifies the photocurrent and photovoltage profiles. The depletion width of the Al/BHJ Schottky junction is 110–120 μm, while the minority electron diffusion length is determined to be 43.8 μm. [ABSTRACT FROM AUTHOR]

The study aimed at complete elimination of lead with minimum energy consumption using electrocoagulation process employing concentric electrodes made of aluminium. The process was optimized using RSM for chosen variables: current intensity, initial pH, initial lead concentration and time. Quadratic models were generated and assessed using four factorial CCD. A significant quadratic regression model was obtained and validated using ANOVA. Complete removal was attained for optimised conditions having 6 pH, 0.3A current intensity, 41 mg/L initial Lead concentration,13 minutes of applied time duration using energy of 0.77 watt-hour per gram removal of lead. Adsorption followed pseudo Ist order kinetics with a good fitting of the Langmuir isotherm model. Overall process was well optimised with quite low operational cost of 0.00092 US $. [ABSTRACT FROM AUTHOR]

This study focuses on developing high-performance electrodes by applying micro/nano structures to aluminum mesh electrodes and evaluating their electrochemical performance through the electroflotation process. First, the most suitable electrode material for electroflotation was selected, followed by the application of micro-nano structures to analyze bubble generation and size distribution in comparison to conventional electrodes. The bubble generation rate and size were used to predict electroflotation efficiency, which was then validated through experiments. The developed electrodes demonstrated a ninefold reduction in purification time compared to traditional electrodes and achieved higher wastewater treatment efficiency than spontaneous flotation. This research highlights the potential of micro-nano structured electrodes to enhance electroflotation processes and offers valuable insights for industrial applications. [ABSTRACT FROM AUTHOR]

AbstractTraditional electrical discharge machining (EDM) electrodes have several limitations such as long machining time, low material removal rate MRR, hazard emissions and high energy consumption. To overcome these limitations, new electrodes (plane and frame U-shaped) were manufactured considering the electrode manufacturing classifications, such as electrode flushing mechanism, electrode cross-sectional area and electrode bottom machining area. Experiments were performed on a die-sinking EDM machine using copper electrodes and aluminum alloy workpieces. The results were compared with those obtained using the conventional electrode. The newly manufactured electrodes significantly improved the EDM process performance, reducing the machining time by more than 50%, which implies a higher MRR. The reduced machining time also led to lower costs, emissions and energy consumption for efficient EDM processes. Additionally, surface roughness measurements were performed to compare the surface quality of the machined areas using different pulse-code generator systems and electrodes. The results showed an improvement in the machined surface quality when using the new electrodes in comparison with the conventional electrode when using a roughing pulse code generator system. [ABSTRACT FROM AUTHOR]

This study explores the application of pillar nanostructures in organic solar cells (OSCs). The aluminum pillar nanostructures (AlPNSs) are fabricated on an active layer surface comprising of a blend poly(3‐hexylthiophene‐2,5‐diyl) and [6,6]‐phenyl C61 butyric acid methyl ester using nanoimprinting. Aluminum back electrodes are formed, resulting in AlPNSs with an imprinted pattern height of 60 ± 6 nm and a pitch of 212 ± 49 nm. Atomic force microscope images and current density versus voltage curves are obtained for the fabricated devices, both with and without AlPNSs. The results indicate a solar cell efficiency increase of 15.16% in the AlPNS OSCs compared to the reference cells. To investigate the role of AlPNSs in the enhancement, impedance spectroscopy, incident photon‐to‐current efficiency, UV–Vis reflection spectroscopy, and finite‐difference time‐domain simulations are performed for the both devices. The results demonstrate that the combination of propagating surface plasmon resonance and light‐trapping properties due to AlPNSs significantly enhances the overall optical performance. This research provides new insights into the potential of imprinted nanostructures for enhancing OSC performance, including their plasmonic and optical characteristics. [ABSTRACT FROM AUTHOR]

In the current study, aluminum electrodes have been employed in electrocoagulation (EC) to remove fluoride ions from groundwater. The effects of various operating process variables of EC, including pH, salt dosage, stirring speed, inter-electrode distance, and current density have been studied, as well as the operating cost and kinetics of the process. The most favorable values of the EC process parameters have been observed, which are effective for the removal of 97.6% fluoride, such as an initial value of pH 7.0, a current density value of 105.86 A/m2, an IED of 1 cm, a dose of salt of 0.33 g/L, a rotating speed of 700 RPM, and a time 40 min. The operating cost for the removal of fluoride (97.6% efficiency) from groundwater by EC was found to be 0.27 US$/m3. The effectiveness of the EC process in the removal of turbidity and TDS from different operating circumstances have also been investigated. First-order kinetics was observed in the kinetic study. The reaction rate constant k increases with CD increase, k decreases with IED increase, and k decreases with initial concentration increase. EDX analysis and FTIR spectra of the sludge confirm the availability of trace amounts of fluoride in the sludge produced. The EC process can effectively reduce the fluoride concentration from synthetic water as well as real groundwater up to below 1.5 mg/L as per WHO recommendations for drinking water. [ABSTRACT FROM AUTHOR]

This paper presents the capacitive behaviour of a Capacitive Micromachined Ultrasound Transducer (CMUT). A Finite Element Method (FEM)-based simulation is proposed to characterize the capacitance of CMUT with different geometrical parameters. The structure of the CMUT under scrutiny consists of an aluminum top electrode on a thin movable membrane of silicon nitride (Si3N4) separated by an air gap from the bottom electrode. The capacitance of the CMUT plays an important role in its proper functionality. The current study attempts to explore the calculation and variation of capacitance with different geometrical parameters. Because of the smaller dimension of the device, the effect of fringing is also taken into account. A new empirical formulation has been developed to study the capacitance of the CMUT with vented cavities, and the accuracy of the theory is justified with FEM simulation for single-vented CMUT. The analytical results are validated with simulation and published experimental results. Keeping the similar geometrical shape of the fabricated structure, this model predicts 94.28 kHz resonant frequency which is very close to the experimental result (106 kHz). [ABSTRACT FROM AUTHOR]

This study examines the reduction efficiency of chemical pollution of freshwater by electrocoagulation (EC) process using aluminium (Al) and iron (Fe) electrodes. Several parameters affecting the EC efficiency were investigated in batch manner. Results indicate that both Al and Fe electrodes can eliminate satisfactorily the chemical pollutants of water. The Fe/Fe pair electrode showed an excellent efficiency in reducing turbidity (≈ 99%) within 30 min of time and at 3.0 A intensity. The COD value increased from 62 to 65% with current intensity from 0.3 to 1.0, and from 70 to 98% following the increase in intensity from 2.0 to 3.0A by using the Al electrode. The removal of COD reached 86% with Fe electrode (for 10 min) while it was 99% with Al electrode (after 45 min) using Al electrode (at 2.5 intensity). It was also found that the P value is greater than 0.05 for COD and less than 0.05 for TSS with both electrodes (Al, Fe). The finding also confirmed that the significant difference exists in the case of TSS reduction and it does not exist in the case of COD. Overall, the study underscores the performance of electrocoagulation using both Al and Fe electrodes for removing chemical pollutants in freshwater, highlighting its potential as a sustainable and adaptable solution for their application in water treatment units. [ABSTRACT FROM AUTHOR]

Open-cast coal mining operations can produce water with high amounts of total suspended solids (TSS). We tested the use of electrocoagulation for the removal of colloidal clay from mine water. Monopolar batch electrocoagulation was performed at the laboratory scale using Al and Fe electrodes and varying the DC current (0.5, 1, and 2 A) and contact time (15, 30, and 45 min). Aluminum electrode electrocoagulation with a current of 2 A and a contact time of 15 min had the greatest TSS removal efficiency (99%), with concentrations decreasing from 5,400 to 23 mg/L. The greatest removal (98 and 99%, respectively) was obtained using an Al electrode with an electric current of 0.5 and 1 A, with 30 min of contact time. With an Fe electrode, the greatest efficiency was achieved with a current of 2 A and a contact time of 30 min. The TSS removal efficiency reached 98% while the concentration dropped to 66 mg/L, followed by 89% and 95% for the 0.5 A-45 min and 1 A-15 min variations, respectively. [ABSTRACT FROM AUTHOR]

Textile wastewater, laden with persistent dyes and non‐biodegradable organics, poses a challenge for treatment in common effluent treatment plants (CETPs) using conventional methods. Pre‐treatment of textile effluents is essential to ensure compatibility with CETPs. The present study employed three‐dimensional (3D) aluminum and graphite electrodes for a sequential electro‐coagulation and electro‐Fenton (EC + EF) process. An experimental plan of 25 experiments was constructed using Taguchi method. The combination resulted in high removal efficiencies: 99.91% for color, 93.20% for chemical oxygen demand (COD), and 91.75% for total organic carbon (TOC) for the operating parameters; for EC, current density (J): 20 mA/cm2, time (t): 45 min, speed of rotation (N): 55 rpm; and for EF, current density (J): 25 mA/cm2, time (t): 50 min, iron concentration: 40 mg/L. Post‐treatment, the wastewater exhibited an enhanced biodegradability index of 0.875, rendering it suitable for CETPs. There was an increase of 11% in the total energy consumption when energy spent during rotation and aeration at the time of EC and EF, respectively, were considered. This energy increases the cost and is not accounted for, in previous research. The energy consumption in kWh per g of COD removed at optimum condition for the hybrid treatment was 0.0314, which is lower than the energy consumption by other electrochemical processes employing plate electrodes. This indicates that 3D electrodes are more energy efficient than plate electrodes. Practitioner Points: Hybrid electrochemical processes can be used as pre‐treatment method for textile effluents.Three‐dimensional electrodes improve removal rates with lower energy consumption.Significant color, COD, and TOC abatement were noted post‐hybrid treatment of textile wastewater.Biodegradability of the textile effluent improves after the hybrid treatment. [ABSTRACT FROM AUTHOR]

This work reports the results of coupling Moringa oleifera seed extract (MOSE) with electrocoagulation (EC) for the remediation of Direct Red 80 azo dye (DR80) from contaminated synthetic aqueous solution and real textile wastewater. The electrochemical treatment was carried out using a pair of aluminium electrodes in monopolar-parallel mode. EC runs determined using Box-Behnken design under the response surface methodology (RSM) for three parameters including current density, pH, and operation time. The EC optimal conditions were current density 0.9 mA/cm2, pH 3, and time 10 min. The maximum experimental DR80 dye removal of 89.37% was close to the model prediction (76.4%). The kinetic study of the EC system represented that the removal of dye obeyed the first-order kinetic model. To improve dye removal efficiency from treated wastewater under optimal conditions, 2.5 mL/L of MOSE was added and the efficiency enhanced to above 98%. SEM and microscopic images of the sludge produced showed that the flocs formed in the hybrid system were denser and thicker than the conventional EC. The economic study revealed that switching from the EC to hybrid process reduced energy and electrode consumption from 0.015 to 0.008 kWh/m3 and 0.016 to 0.014 kg/m3, respectively, for 98% DR80 dye removal. MOSE has a substantial effect on the EC performance. Therefore, the EC/MOSE coupling process is recommended for the treatment of coloured wastewater due to its high efficiency, short operation time, and electrode and energy consumption costs. [ABSTRACT FROM AUTHOR]

This study assessed the removal efficiency of ammonia nitrogen from tannery wastewater by combining electrocoagulation, ozonation, and ion exchange technologies. For this purpose, an electrocoagulation reactor equipped with aluminum electrodes, an ozonation tank, and a filtration system with zeolite were employed. The electrocoagulation treatment applied the response surface methodology with a 3k factorial design with the following two factors: current intensity (I) ranging from 3 to 7A, and treatment time (t) from 10 to 30 min; the removal percentage of total suspended solids (TSS) is set as a response variable. Results indicate that the treatment time and current intensity were significant for the removal of total suspended solids TSS, at a confidence level of p < 0,05. Under these conditions, a TSS, removal efficiency of 98% was achieved. Through the electrocoagulation process, the chemical oxygen demand (COD) was reduced by 58%, while in the ozonation tank, an additional 23% of COD was removed. The filtration stage demonstrated that 13X HP zeolite can exchange ions with the ammonia nitrogen from tannery wastewater, wherein a 39% removal efficiency is reached at equilibrium. Thus, the integration of various treatment methods is a viable alternative to reduce wastewater from the tannery industry. The novelty of this research lies in the integration of three methods for treating tannery wastewater. The results show that the combination of these treatments provides a more effective solution for removing the pollutant load, especially nitrogen, compared to the use of individual treatment methods alone. The study opens new perspectives for optimizing multi-stage treatment processes. [ABSTRACT FROM AUTHOR]

A batch electrocoagulation (EC) process using aluminum electrodes was optimized for the removal of natural organic matter (NOM) and subsequent reduction in total trihalomethane (TTHM) formation potential from synthetic (SynW) and river water (RW) samples. Optimum operating conditions were found to be 45 min of electrolysis time, an initial NOM concentration of 10 mg/L , and an applied voltage of 15 V. Initial NOM concentrations tested were 3, 5, 10, 15, 20, 30, 40, and 50 mg/L and treatment efficiency increased with increasing initial concentration. The kinetic study demonstrated that NOM removal followed second-order kinetics. NOM removal resulted in the reduction of trihalomethanes (THMs) formation in treated water. THM concentrations were measured in untreated and EC-treated water. Bromodichloromethane had the highest removal (92.4%) compared to trichloromethane (89.5%) after 10 min. The TTHM concentration after a 10–30 min treatment was below the US Environmental Protection Agency (USEPA) maximum contaminant level of 80 μg/L. After 60 min, the TTHM concentration in the RW samples was reduced by 77.5%, which was considerably less than the reduction in the SynW samples (89.7%) within 10 min. The lower THMFP removal from RW may be due to interference from natural or anthropogenic constituents. The total amount of sludge generated in experiments was compared with the estimate derived using Faraday's equation. A current efficiency of 1.4 was obtained, indicating super-faradaic behavior of the EC process at the optimum operating conditions. Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to characterize the generated sludge and entrapment of NOM in aluminum hydroxide [ Al(OH)3 ] flocs as the most likely removal mechanism. At optimum operating conditions, the energy consumption was 2.391 kWh/m2. Thus, EC is an effective method for reducing NOM and THMFP from RW samples. [ABSTRACT FROM AUTHOR]

The electrical discharge machining is very successful and generally recognized for producing complicated shapes and small openings with exceptional precision. The objective of this study is to assess the impact of different electrical discharge machining parameters on the attributes of the machining process. The evaluation of the machining process was conducted based on the workpiece's material removal rate, the rate at which the electrodes wear, and the level of surface roughness. Simultaneously achieving a high material removal rate, low electrode wear rate, and high surface roughness is not possible with a specific combination of approaches due to their contradicting nature. Frequently, it is necessary to independently apply many measures instantaneously in order to assess their impact on various responses. This research investigates the machining of high carbon high chromium steel making use of electrical discharge machining with aluminum, copper, and graphite electrodes. The study focuses on the impact of different current intensities on the rate of material removal, electrode wear, and surface roughness. The experimental results demonstrate that the highest material removal rate (mmcubicmin−1) is achieved at a current density of 12 A when using a copper electrode (54.67), as opposed to aluminum electrode (22.91) and graphite electrode (29.43). [ABSTRACT FROM AUTHOR]

Aluminum batteries have become the most attractive next-generation energy storage battery due to their advantages of high safety, high abundance, and low cost. However, the dendrite problem associated with inhomogeneous electrodeposition during cycling leads to low Coulombic efficiency and rapid short-circuit failure of the aluminum metal anode, which severely hampers the cycling stability of aluminum battery. Here we show an aluminum anode material that achieves high lattice matching between the substrate and the deposit, allowing the aluminum deposits to maintain preferred crystal plane growth on the substrate surface. It not only reduces the nucleation barrier of aluminum and decreases electrode polarization, but also enables uniform deposition of aluminum, improving the cycling stability of aluminum batteries. Aluminum anode with (111) preferred crystal plane can stably 25000 cycles at the current density of 5 A·g−1, with a capacity retention rate of over 80%. An aluminum anode is proposed to achieve high lattice matching between the aluminum anode and the aluminum deposit, allowing the aluminum deposits to maintain preferred crystal face growth on the aluminum anode surface. [ABSTRACT FROM AUTHOR]

Electrocoagulation has demonstrated its efficacy in treating industrial effluents by effectively removing pollutants, particularly metallic contaminants. The electrochemical processes occurring at aluminum electrodes have shown excellent performance in this regard. In this study, electrocoagulation experiments were conducted on an industrial effluent originating from an electroplating bath situated in Casablanca, Morocco. The primary objective was to eliminate chromium in the effluent and reuse the processed water for other applications within our facility. To achieve this goal, we systematically optimized various operational parameters influencing the electrocoagulation efficiency, including electrical voltage, electrode material, stirring speed, and electrode spacing. Additionally, we assessed their impact on pH, conductivity, and chromium concentration. The experiments were conducted in a well-mixed reactor using an industrial solution containing a high concentration of chromium, specifically 1 g/l of Cr (VI). The chromium removal efficiency was evaluated under specific operational conditions, including the use of aluminum electrodes, regulated voltages of 6 volts and 12 volts, an optimal stirring speed of 600 rpm, and an electrode spacing of 2 cm. [ABSTRACT FROM AUTHOR]

The dairy industry is classified, worldwide, as one of the main wastewater‐generating industries. The objective of the study was to evaluate the effect of parameters on the percentage of turbidity (TB) removal and chemical oxygen demand (COD), using as pretreatment a combined coagulation process using a biocoagulant composed of chitosan and Opuntia ficus-indica mucilage (OFI): chitosan‐mucilage (Q‐M from 1 to 9), and an electrocoagulation process with operational variables of biocoagulant dose (0.025, 0.05 y 0.1 g/L), current density (30, 40 y 50 mA/cm2), and time (10, 15 y 20 minutes). A monopolar glass reactor with aluminum electrodes was assembled by applying the response surface approach methodology. Additionally, using the Box–Behnken mathematical model for the removal of TB and COD, the effects and interactions of the factors and experimental design levels (considering control formulations using triplicates) were evaluated. An analysis of variance was performed to evaluate model responses and optimal conditions. The experimental results showed that the formulation of the compound biocoagulant Q‐M‐5 in doses of 0.99 g/L achieves 98.44% turbidity removal and 81.72% chemical oxygen demand removal. The dose of the compound biocoagulant has a significant positive effect as does the current density of 30 mA/cm2 and time of 19.05 min; that is, its efficiency in removing turbidity and chemical oxygen demand increases when using these parameters. It is concluded that the use of the biocoagulant composed of chitosan and Opuntia ficus-indica mucilage (Q‐M‐5) as the primary treatment of whey wastewater provides evidence for the literature, showing that it is also a low‐cost, ecological, and easy‐to‐apply natural coagulant. [ABSTRACT FROM AUTHOR]

Electrolytic capacitors store larger amounts of energy thanks to their thin dielectric layers and enlarged surface area. However, the benefits of using a liquid electrolyte are at the expense of the possibility of leakage, evaporation, or rupture of the device over time. As a solution, solid electrolytes, such as conductive polymers, substitute the liquid ones decreasing the internal resistance and enlarging the lifetime of these devices. PEDOT:PSS is a widely used conductive polymer in the formation of solid electrolytic capacitors. However, using the enlarged surface of the porous electrodes efficiently requires industrial processes, the efficacy of which has not been explored. In this work, porous aluminium electrodes with dielectric layers of different thicknesses were coated with PEDOT:PSS at different levels of doping in order to study the efficiency of the production of solid electrolytic capacitors in industry. The combination of odd random phase electrochemical impedance spectroscopy (ORP-EIS) with surface characterization techniques (SEM-EDX, GDOES) formed a methodology that allowed the study of both the electrical properties and the level of impregnation for these model systems. All samples consisting of a porous aluminium electrode with an amount of PEDOT:PSS deposited on top resulted in an inefficient degree of penetration between the two electrodes. However, the electrochemical analysis proved that the use of dopants produces systems with the highest capacitive properties. Consequently, the evolution towards better solid electrolytic capacitors does not rely solely on the proper coverage of the porous electrodes, but on the proper electrical properties of the PEDOT:PSS within the pores. [ABSTRACT FROM AUTHOR]

The present study focuses on the technique of hardness removal by using a novel reactor performing an electrocoagulation (EC) process. The variation of alkalinity is also recorded. Continuous flow experiments were conducted for Total Hardness (TH) removal using a transparent plastic reactor using aluminum plate electrodes that have holes so that the water flows through the plates in a zigzag way. The influence of various operating parameters such as the number of plates (two and four), flow rate (600, 1000 L/h), and water type (Tigris River & rejected water from Reverse Osmosis system RO) was investigated. The results showed that an increase in the number of electrodes led to an increase in the total hardness removal efficiency. In addition, the increase in the flow rate led to a decrease in the removal efficiency. For the rejected RO water type, the highest hardness removal rate was 16.16% for 4 plates electrodes and 600 L/h flow rate while for the river water was 29% for 4 plates electrodes and 1000 L/h [ABSTRACT FROM AUTHOR]

The presence of a large amount of organic and inorganic pollutants in dairy effluent is a substantial environmental issue. This study investigated electrocoagulation (EC) as a potential treatment method for dairy wastewater under different operating conditions, such as applied voltage (5–25 V), electrolysis time (30–90 min), and inter-electrode distance (1–2 cm) by using aluminum electrodes. This study focuses on achieving the maximum removal of BOD, COD, and nitrate in dairy effluents with the aforementioned operating conditions. The process was optimized using the response surface methodology (RSM) and Taguchi method. RSM method optimized the electrocoagulation operating conditions such as the voltage at 23.75 V, time of 90 min, and inter-electrode distance at 1.07 cm. This optimization achieved the maximum removal percentage of BOD, COD, and nitrate at 79.06%, 84.35%, and 79.64%, respectively, in dairy effluent. Taguchi method optimized the electrocoagulation parameters such as the voltage at 25 V, time duration of 90 min, and inter-electrode distance of 1.00 cm, showcasing improved removal percentages of BOD, COD, and nitrate as 90.54%, 89.28%, and 82.74% respectively. The current study attempts to understand the optimization efficiencies between Taguchi method and response surface method for diary wastewater treatment. [ABSTRACT FROM AUTHOR]

The present research offers an innovative approach to enhance the safety and mobility of people with visual impairments by using a smart white cane sensor. Herein, an aluminum electrode, Kapton film, and an inexpensive PET substrate are employed to develop an origami‐shaped multilayered triboelectric nanogenerator (TENG) device. The multilayered integration of three‐unit TENGs produces output with a high power of 51 μW at 50 MΩ, along with 155 V and 4.5 μA. Capacitor charging, low‐power electronics powering, and the integration of mechanoluminescent materials are demonstrated. The integration of mechanoluminescent materials enables efficient identification of visually impaired people in regions with poor lighting. A single‐electrode TENG is also implemented for successful surface material detection. To further enhance the sensor's capabilities, digital signal processing techniques are employed for obstacle recognition on their route. The intelligent white cane sensor effectively detects obstructions, offering the user instantaneous feedback and enabling more secure navigation in sophisticated environments. This study highlights the possibility of integrating TENG technologies to provide a complete solution for people with visual impairments. The smart white cane sensor has the potential to greatly increase the safety and independence of visually impaired people in a variety of outdoor and public spaces. [ABSTRACT FROM AUTHOR]

Marine pipeline vibration condition monitoring is a critical and challenging issue, on account of the complex marine environment, while powering the required monitoring sensors remains problematic. This study introduces a vibration sensor based on a ball triboelectric nanogenerator (B-TENG) for marine pipelines condition monitoring. The B-TENG consists of an acrylic cube, polyester rope, aluminum electrodes, and PTFE ball, which converts vibration signals into electrical signals without the need for an external energy supply. The experimental results show that B-TENG can accurately monitor the frequency, amplitude, and direction of vibration in the range of 1–5 Hz with a small error of 0.67%, 4.4%, and 5%, and an accuracy of 0.1 Hz, 0.97 V/mm, and 1.5°, respectively. The hermetically sealed B-TENG can monitor vibration in underwater environments. Therefore, the B-TENG can be used as a cost-effective, self-powered, highly accurate vibration sensor for marine pipeline monitoring. [ABSTRACT FROM AUTHOR]

Arsenic (As) contamination is a severe problem in drinking-water sources. This study designed and investigated a novel combined electrocoagulation–filtration (ECF) system to investigate As treatment and filtration in drinking water in collaboration with HANDS-Pakistan and Medico International, Germany. Two separate pilot-scale ECF systems were designed and developed with an electrocoagulation (EC) unit and a commercially available PAUL® filter configured with vertical flat-sheet ultra-low-pressure membranes of 0.04 µm pore size for the combined treatment and filtration of different As concentrations. Real drinking water at different As concentrations, i.e., 100, 200, and 300 μg/L were tested on one ECF system with EC electrodes of iron (Fe) and another system with aluminum (Al), at different treatment times (0, 5, 10, 20, 45, 60, 120, 180 min), at a fixed current density (12 mA/cm2) and water flow rate of 1 L/min. The initial results showed 99% As removal within 5 min with the combined ECF treatment for both electrodes of Fe and Al. In addition, the effect of ECF on different water-quality parameters and the ionic interference on ECF performance and As filtration were analyzed. The results showed the promising potential of combined ECF treatment and filtration for treating and purifying As. [ABSTRACT FROM AUTHOR]

This study aims to improve COD, NH3‐N, and turbidity removal from Bingöl's leachate using a single‐reactor integrated electrocoagulation (EC)–coal‐based powdered activated carbon (CBPAC) process under various experimental conditions. In the EC‐CBPAC process, three stainless‐steel cathodes and three aluminum electrodes were connected to the negative and positive terminals of the power supply, respectively. The initial concentrations in the leachate were 1044 mg O2/L for COD, 204 mg/L for NH3‐N, and 57 NTU (or 71.25‐mg (NH2)2H2SO4/L) for turbidity, respectively. After a 40‐min EC‐CBPAC process, with a CBPAC dosage of 5 g/L and pH of 5 for COD and turbidity, and 9.5 for NH3‐N, the optimum removal efficiencies for COD, NH3‐N, and turbidity were achieved at 92%, 40%, and 91%, respectively. When the EC process was applied without CBPAC under the same experimental conditions, the removal efficiencies of COD, NH3‐N, and turbidity were 87%, 28%, and 54%, respectively. Before and after the EC‐CBPAC process, the Brunauer–Emmett–Teller (BET) surface area, pore volume, and mean pore diameter of the CBPAC were found to be (888 m2/g, 0.498 cm3/g, and 22.28 Å) and (173 m2/g, 0.18 cm3/g, and 42.8 Å), respectively. The optimum pseudo‐first‐order (PFO) rate constants for COD, turbidity, and NH3‐N were determined to be 3.15 × 10−2, 4.77 × 10−2, and 8.8 × 10−3 min−1, respectively. With the current density increasing from 15 to 25 mA/cm2, energy consumption, unit energy consumption, and total cost increased from 68.7 to 122.4 kWh/m3, 6.948 to 15.226 kWh/kg COD, and 0.85 to 1.838 $/kg COD, respectively. Practitioner points: EC‐CBPAC process has greater COD, NH3‐N, and turbidity removal efficiency than EC process.COD and turbidity achieved their optimum disposal efficiencies at 92% and 91%, respectively, at pH 5The most efficient disposal efficiency for NH3‐N was observed to be 40% at pH 9.5.EC‐CBPAC process increased removal efficiencies for COD, NH3‐N, and turbidity by 20%, 19%, and 38%, respectively, compared with EC alone.The turbidity, NH3‐N, and COD disposal fitted PSO model due to high correlation values (R2 0.94–0.99). [ABSTRACT FROM AUTHOR]

[Display omitted] This study presents a novel Aluminium foil-based electrode characterized by its affordability, flexibility, and ease of modification with carboxylic moiety-containing organic molecules. Upon foil modification with Aluminium nanoparticles and EDTA (AlNP-EDTA/AlE), the modified electrode exhibits remarkable activity in the oxidation of lead at potentials around −0.4 V. The lead signal is derived from the oxidation of lead deposited on the electrode surface using anodic stripping voltammetry (ASV). The addition of EDTA to AlNP/AlE increased the anodic peak current of lead by more than 500 %. The surface characterization of the electrode was performed by scanning electron microscopy (SEM) and infrared spectroscopy (IR), while its electroactive properties were evaluated by cyclic voltammetry (CV) and electrical impedance spectroscopy (EIS). Optimal operating parameters include pH 2.1, square-wave voltammetry (SWV) with an accumulation time of 60 s and an accumulation potential of −0.8 V. A low detection limit of 0.20 µmol/L and a relative standard deviation (RSD) of 3.0 % were achieved using five different electrodes. The effectiveness of AlNP-EDTA/AlE was further demonstrated with consistent results in biological samples spiked with Pb. [ABSTRACT FROM AUTHOR]

Imidacloprid is still a widely used neonicotinoid insecticide that is banned in many countries because of the associated environmental risks. Due to the inefficiency of conventional wastewater treatments for pesticide removal, new treatment methods are being investigated. Electrochemical methods, including electrocoagulation (EC), seem to be promising alternatives considering their effectiveness in removing various pollutants from wastewater. The aim of this study was to investigate the effects of electrode material, current density, ultrasound, and operation time on the efficiency of imidacloprid removal from a model solution by EC. The combination of aluminum electrodes and 20 A of applied current for 20 min resulted in total imidacloprid degradation. A simplified energy balance was introduced as a form of process evaluation. Combining ultrasound with EC resulted in 7% to 12% greater efficacy than using only EC. [ABSTRACT FROM AUTHOR]

The long-term feasibility and efficiency of microbial electrolysis cells (MECs) depend primarily upon several crucial parameters. However, they show promise for sustainably producing biohydrogen (bioH 2). This study investigates a newly designed biohydrogen reactor by studying the effects of several variables on the production of bioH 2 , including applied voltage, electrode material, and gas sparging with CO 2 and N 2. The study aims to optimize the system for improved efficiency and production performance. The results of this study show that both electrode type and applied voltage affect bioH 2 production where choosing the right inoculum has a significant impact on the catalytic efficiency. The aluminum electrodes significantly help produce the most bioH 2 production at 2.0 V with 884 mL/L in 11.25 min, while emphasizing the significance of material characteristics. The reduced partial pressure from CO 2 sparging, up to a point, improves bioH 2 generation. The N 2 gas sparging further demonstrates an increased efficiency where the ideal flow rates are dependent on the size of the MEC system. The highest bioH 2 production rates for CO 2 and N 2 sparging are measured as 821 mL/L and 813 mL/L in 4.25 min and 11.50 min at a volume of 400 mL/min and 300 mL/min, respectively. The results of this study further advance our knowledge of and ability to optimize MEC systems for long-term, sustainable bioH 2 production. [Display omitted] • A maximum hydrogen production of 892 mL is observed by microbial electrolysis cells. • Hydrogen production is improved in the presence of carbon dioxide and nitrogen gases. • Aluminum electrodes provide the highest hydrogen production at improved conditions. • The carbon dioxide input enhances the performance by six times considering time. • Maximum hydrogen production of 884 mL is achieved at a flow of 100 mL-N 2 /min. [ABSTRACT FROM AUTHOR]

The use of conductive polymers in aluminium electrolytic capacitors prevents leakage and enlarges the temperature use range when compared with their liquid counterparts. PEDOT:PSS is an outstanding candidate due to its tunable properties, i.e., electronic conductivity (10−5 to 103 S/cm), and its high thermal stability. As a result of their synthesis, PEDOT:PSS dispersions are characterized by a low pH value, which can influence pH sensitive materials such as aluminium. However, no work to date has studied the interaction between PEDOT:PSS dispersions and aluminium oxide substrates. In this work, the interface and interaction between PEDOT:PSS and an aluminium electrode were studied for the first time via odd random phase electrochemical impedance spectroscopy and analysed post mortem by SEM and AFM characterization. PEDOT:PSS dispersions at different pH values (1.9, 4.9, 5.8) were applied in a layered manner onto a non-etched aluminium substrate with a grown oxide layer on top, which provided a model system for the analysis of the interface. The analysis showed that the acidic PEDOT:PSS dispersions attacked the aluminium substrate, forming pores on the surface, but had a positive impact on the capacitance of the aluminium oxide/PEDOT:PSS systems. On the other hand, neutral dispersions did not affect the aluminium electrode, but showed poor layer formation properties, and the electrochemical analysis displayed a dispersion of results ranging from capacitive to resistive behaviour. [ABSTRACT FROM AUTHOR]

A lack of fresh water is one of the most significant problems currently affecting humanity. Water scarcity also affects industries, with the mining industry being one of the most affected. One possible solution to water scarcity is the recirculation of water. Water in mining is usually treated with physicochemical methods, but in metallurgical processes, reagents are added, accumulate until reaching the point of saturation, and are often not successfully removed. In this sense, electrocoagulation has shown great efficiency in the treatment of organic contaminants, heavy metals, and metallic ions, and was applied in this study to eliminate ions and undesirable organic compounds present in mining–metallurgical process water. Furthermore, this process has shown great efficacy in relation to toxic metals like arsenic because their presence reduces the efficiency of other processes such as flotation. In this study, two types of electrodes were used: stainless steel and aluminum. The best results were achieved with stainless steel electrodes, which were able to eliminate 90% of copper ions in water. The turbidity of the water during the process was measured to determine the amount of solid present in the water, and a reduction of around 95% was observed when using aluminum electrodes. The sedimentation of clots occurred in two stages: Firstly, the coagulant was formed to trap organic matter as its size increased, until a particle size that was sufficient for settling was achieved. A zero-order kinetic model was fit for this stage of the process. Secondly, the formed clots continued to settle, and a second-order kinetic model was fit for this stage. Flotation tests were carried out on the process and electrotreated water to evaluate the recovery of Zn, Pb, Ag, and Au. An increase of 1.5% was found for gold, and an increase of 2% was found for silver, while a significant improvement was identified for zinc, augmenting recuperation by 30% when electrotreated water was used. For lead, no considerable change in recovery was observed in either form of water. The formed clots were analyzed using Scanning Electronic Microscopy, and we found that metal ions were trapped in the clots. This study demonstrates the potential of electrocoagulation for clarifying mine water, which is ordinarily very difficult to clarify. [ABSTRACT FROM AUTHOR]

Aluminum current collectors are widely used in nonaqueous batteries owing to their cost-effectiveness, lightweightness, and ease of fabrication. However, they are excluded from aqueous batteries due to their severe corrosion in aqueous solutions. Here, we propose hydrolyzation-type anodic additives to form a robust passivation layer to suppress corrosion. These additives dramatically lower the corrosion current density of aluminum by nearly three orders of magnitude to ~10−6 A cm−2. In addition, realizing that electrochemical corrosion accompanies anode prelithiation, we propose a prototype of self-prolonging aqueous Li-ion batteries (Al ||LiMn2O4 ||TiO2), whose capacity retention rises from 49.5% to 70.1% after 200 cycles. A sacrificial aluminum electrode where electrochemical corrosion is utilized is introduced as an electron supplement to prolong the cycling life of aqueous batteries. Our work addresses the short-life issue of aqueous batteries resulting from the corrosion of the current collector and lithium loss from side reactions. Aqueous batteries have a short lifespan due to Al current collector corrosion and Li loss from side reactions on the anode. Here, the authors propose a prototype of self-prolonging aqueous Li-ion batteries by introducing hydrolyzation-type anodic additives to regulate Al corrosion-passivation. [ABSTRACT FROM AUTHOR]

Electrical Discharge Machining (EDM) employing coated electrodes represents a relatively unexplored research avenue, with limited published findings to date. The choice of coating material significantly influences the EDM machining process, directly impacting the adjustment of technological parameters. Consequently, an in-depth investigation into the optimization of technological parameters for EDM with coated electrodes is imperative, aiming to propel the practical application of this innovative technique. This study focuses on determining the technological parameters for EDM utilizing an aluminum (Al) electrode coated with graphene for machining titanium alloy (Ti-6Al-4V). The research addresses a multi-objective optimization problem, with Material Removal Rate (MRR) and Tool Wear Rate (TWR) serving as key quality indicators. The integration of the Taguchi method with the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is employed to address the multi - objective nature of the optimization challenge. The obtained results pinpoint optimal process parameters as U = 55 V, I = 5 A, and Ton = 1500 µs, resulting in an MRR of 6.57 mg/min. An in-depth analysis and evaluation of the machined surface quality with the coated electrode under optimal conditions are conducted. The TOPSIS method emerges as a fitting solution for this multi-objective optimization problem, offering simplicity in its computational steps. [ABSTRACT FROM AUTHOR]

Produced water (PW) is the largest by-product that comes out of the oil wells during oil and gas (O&G) field exploration. PW contains high-salt concentration along with other organic and inorganic components; therefore, PW must be treated before disposal. Electrocoagulation (EC) is an effective treatment method to remove pollutants from PW which has been the focus of many experimental studies; however, a mathematical model specifically for PW treatment by EC has not been developed yet. In this work, a comprehensive mathematical model has been developed to elucidate the role of EC operating parameters on the PW treatment performance and determine the mechanism for COD (Chemical Oxygen Demand) removal. The present model considers and identifies the dominant Al-hydroxy complex species and their contribution to the COD removal from synthetic PW samples by estimating their rate constants and comparing their magnitudes and investigates multi-scale modelling of the EC reactor. The influence of working parameters such as current density, initial pH, interelectrode distance, mixing speed and solution volume of PW on Al coagulant production and COD removal was investigated and modelled. The study estimates the rate constants of the reactions taking place for COD removal by EC process and by comparing their magnitudes identifies the dominant reactions and coagulant species involved in the process. The mathematical model prediction of COD removal fits well with the experimental data at 10 mA cm−2, 15 mA cm−2 and 20 mA cm−2 current density with R2 value of 0.96, 0.97 and 0.92, respectively and for dissolved Al concentration R2 value of 0.96, 0.99, and 0.97, respectively. The simulated results reproduced a good fit at initial pH of 6.1, 7.3 and 8.6 with R2 value of 0.92, 0.96 and 0.98, respectively for COD removal. The mathematical model and the experimental results showed the role of dominant Al-hydroxy complex species such as Al OH 2 + , Al OH 2 + , Al OH 3 , Al 2 OH 2 + 4 and Al OH 4 - in controlling the COD removal process. Under different operating conditions considered in the study, the model also predicted the COD removal performance of the EC reactors at different reactor volumes with R2 value of 0.96 for higher solution volume and larger reactor. The model presented and rate constants determined in the study will provide a theoretical basis for designing, scaling up and operating the EC reactor for oil-field PW treatment. [ABSTRACT FROM AUTHOR]

This study investigates the effect of voltage on the removal of polypropylene microplastics (PPMPs) from artificial wastewater via an electrocoagulation (EC) process using iron (Fe) electrodes. The effect of the voltage was investigated by conducting multiple continuous flow experiments at three different voltage values (10, 20, and 30 V). The findings demonstrated that the turbidity value increased gradually as the initial voltage increased, from 6.67 NTU at 10 V to 74.37 NTU at 30 V. In this EC process, in which Fe electrodes are utilized to remove the PPMPs, it is believed that 20 V provides optimal support. Kinetic studies showed that the process followed a first-order kinetic model with a kinetics rate constant (k) of 0.0143 min-1 and a coefficient of determination (R²) of 0.9702. The findings demonstrated that voltage is a significant parameter in the EC process employing Fe electrodes to remove PPMPs from wastewater. [ABSTRACT FROM AUTHOR]

Bamboo is one of the green building materials that have been used for centuries. Combining with metal materials will endow bamboo with new functions, such as weather resistance, anti-corrosion, conductivity, and electromagnetic shielding. However, there is a natural barrier between bamboo and metal materials. This paper proposes fabrication of novel bamboo-based metal composites (BMC) which are composed of bamboo substrate and metal coating, without any adhesive, using an efficient and sustainable arc thermal spraying technique. In this method, the metal wire is melted and deposited on the bamboo substrate through a high-temperature heat source. In the feasibility experiment, arc spraying using aluminum as the wire electrode was selected. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were used to observe and test the fabricated specimens. It was demonstrated that when the spraying voltage was 40 V, the deposition rate was as high as 5.8 g/min with the average thickness of the metal coating exceeding 400 μm. The surface of the BMC aluminum coating was flat, continuous, and compact with an average roughness of about Ra 3.0 μm. Based on experimental results, the integrity of bamboo substrate in thermal spraying was discussed. Results from SEM–EDS test showed that there are crack areas and adhesion areas between bamboo and metal coatings, and the highest bonding strength exhibited over 1.0 MPa. This work provides a new practice of fabricating novel BMC through a green manufacturing method with high efficiency. The findings of this study may be useful in understanding the preparation of BMC and can help find their suitability for a wide range of applications. [ABSTRACT FROM AUTHOR]

The present study elaborates the electrocoagulation process for the removal of nitrates from synthetic and real groundwater. Electrocoagulation treatment has a positive effect on the quality of groundwater in general and the removal of nitrate in particular, which is one of the most potent pollutants found in groundwater. Moreover, it is supposed that nitrate removal mechanisms are likely to be dependent on operational parameters like applied current, electrode material, initial concentration of nitrates, and pH of the solution, etc. Therefore, in the present study various process parameters have been optimised in terms of nitrate removal efficiency. Experiments were performed using batch process at different initial concentration of nitrates (100–500 mg/L), pH (6.0–12), stirring speed (100–500 rpm), inter-electrode distance (0.5–2 cm) and electrolysis time (30–180 min). Further, the effect of co-existing ions using KNO3, Ca(NO3)2 and Mg(NO3)2 in the presence of NaCl and Na2SO4 was investigated. Maximum 98%, Nitrate removal efficiency was obtained at inter-electrode distance 1 cm, agitation speed 300 rpm, electrolyte concentration of 1.1688 (g/L) NaCl, current 1.5 A and time 180 min for initial nitrate concentration of 100 (mg/L). Isotherm and kinetics models have been studied and it was observed from the present investigation that the process follows pseudo-second-order kinetics. The Freundlich isotherm model simulations match satisfactorily with the experimental observations. Further, optimised parameters were used to remove nitrates from real groundwater and 92.5% removal efficiency was attained. [ABSTRACT FROM AUTHOR]

This study investigates landfill leachate treatment using aluminum (Al-Al) and iron (Fe-Fe) electrodes in electrocoagulation (EC). Aluminum experiments revealed COD removal percentages of 22% (pH 7.4) and 20% (pH 6.0), while iron demonstrated higher efficiency at 32% (pH 7.4) and 30% (pH 6.0). Both processes excelled at neutral pH, with Fe-Fe EC displaying superior removal efficiency. To address electrode passivation, external aeration improved COD removal (31% to 61%) under specific conditions (3 V, pH 7.4, 60 min). The EC process established a neutralization mechanism, eliminating the need for further treatment before discharge. External aeration and polarity changes at intervals mitigated passivation, enhancing COD removal (61% to 69%). Voltage testing (1 V, 3 V, 5 V, 7 V) revealed a direct correlation, peaking at 91% efficiency with 5 V. Specific energy consumption was 2.34 kWh g−1, and sludge generation varied with voltage. The combined use of external aeration and polarity shifts resulted in 270 ml of sludge, demonstrating improved efficiency in the EC process. [ABSTRACT FROM AUTHOR]

Vertical organic field effect transistors (VOFETs) are of paramount importance due to their fast switching speed, low power consumption, and higher density on a chip compared to lateral OFETs. The low charge carrier mobility in organic semiconductors and longer channel lengths in lateral OFETs lead to higher operating voltages. The channel length in VOFETs can be less than 100 nm which reduces the size of the channel and hence the operating voltages. Another important factor in the operation of VOFETs is the thickness and width of the source electrode. The channel length, source electrode thickness and width sets the miniaturization limit of the VOFETs. The graphene monolayer can be exploited as a source electrode due to its thinness, high carrier mobility, and metallic behaviors. However, for better gate modulation, perforations in the source material are desired. Here, we simulate the VOFET having perforated graphene monolayer as a source electrode and n-type organic semiconductor N, N′-dioctyl-3,4,9,10-perylenedicarboximide (PTCDI-C8) as an active channel material, while aluminum as a drain electrode to predict the best-miniaturized device. The miniaturization limit of such a VOFET has a limit to the gate opening/perforation in which the minimum source width is 10 nm, as in the sub 10 nm range graphene starts behaving like a semiconductor. The subthreshold swing, deduced from the drain current (J D) versus gate voltage (V G) graph, advocates the limit of the organic semiconductor height/channel length to 50 nm, while 50 nm for the gate. [ABSTRACT FROM AUTHOR]

Micro drilling using Electrical Discharge Machining (MD-EDM) has emerged as a prominent technique in precision manufacturing, offering the capability to create small and intricate holes. This study focuses on investigating the influence of input process parameters on nickel-based superalloy (Ni3 (Ti, Al)) material, while the electrode materials studied are copper, aluminum and tungsten, with varying electrode diameters of 0.4 mm, 0.5 mm and 0.6 mm. The research encompasses an L9-orthogonal array (L9-OA) in which the Machining Voltage, Peak Current (IP), Pulse off time (Poff) and Servo Standard Voltage (SVR) are varied. Three levels of Machining Voltage (4 volts, 6 volts and 8 volts) and IP are selected. Moreover, scanning electron microscope (SEM) imaging is employed to observe and analyze the morphological characteristics of the drilled holes. The experimental results reveal that the choice of electrode material and diameter significantly influences the SR of the drilled holes. Copper electrodes demonstrate the lowest SR, followed by tungsten and aluminum electrodes. Smaller electrode diameters result in improved surface finish due to reduced discharge energy concentration. Additionally, increasing the Machining Voltage leads to larger discharge energy and heat, resulting in increased SR. SEM imaging demonstrates distinct differences in hole morphology based on the electrode material and diameter, with copper electrodes producing cleaner and more precise holes with minimal recast layer formation compared to aluminum and tungsten electrodes. The influence of Machining Voltage is observed through the presence of craters and debris in higher voltage conditions. [ABSTRACT FROM AUTHOR]

An ultra‐fast electrochemical capacitor (EC) designed for efficient ripple current smoothing was fabricated using vertically oriented MoS2 (VOM) nanoflakes deposited on freestanding carbonized cellulose (CC) sheets as electrodes. The daily used cellulose tissue sheets were transformed into electrode scaffolds through a rapid pyrolysis process within a preheated furnace, on which VOM nanoflakes were formed in a conventional hydrothermal process. With these ~10 μm thick VOM‐CC electrodes, ultrafast ECs with tunable frequency response and specific capacitance density were fabricated. The ECs with a cell‐level areal capacitance density of 0.8 mF/cm2 at 120 Hz were demonstrated for ripple current filtering from 60 Hz to 60 kHz. At a lower frequency response level, EC cell with a large capacitance density of 4.8 mF/cm2 was also demonstrated. With the facile and easily scaled up process to producing the nanostructured electrode, the miniaturized VOM‐CC based ECs have the potential to substitute the bulky aluminum electrolytic capacitors for current smoothing and pulse power applications. [ABSTRACT FROM AUTHOR]

This study assessed the effectiveness of integrating electrocoagulation, magnetic fields, and ozonation technologies to remove chemical oxygen demand (COD) and total suspended solids (TSS) from tannery wastewater. Furthermore, the effects of their key operating factors were determined. To achieve this goal, an electrocoagulation reactor coupled with a magnetic-field generator was used and the response surface methodology was applied through a Box-Behnken experimental design. Here, current intensity (I), treatment time (T), and ozone concentration (O3) are considered the influencing factors. Likewise, the removal percentages of COD and TSS serve as response indicators. The results indicate that T, I, and O3 are significant for the removal of COD and TSS at a confidence level of p-value < 0.05. For COD, the optimal operating conditions are I = 6.8 A, T = 30 min, and O3 = 10 mg/l; and for TSS, the optimal conditions are I = 5.72 A, T = 28 min, and O3 = 7.8 mg/l. These conditions yield removal efficiencies of 41.8% for COD and 97.9% for TSS. The findings suggest that integrating these technologies is a viable alternative for mitigating the pollution issues caused by the tannery industry. [ABSTRACT FROM AUTHOR]

In this work, it was attempted to evaluate and demonstrate disinfection effectiveness of an electrochemical process to entirely remove coliform from wastewater effluent following secondary treatment. For the tests, an experimental bench-scale batch electrochemical cell was constructed, and aluminum electrodes were employed in the electro-disinfection reactor. In the electric disinfection phase, wastewater samples were put in the reactor/disinfector and a direct current (DC) was applied to it. According to findings, a significant decrease occurred in the total number of coliforms in the treated wastewater, and a high improvement occurred in the effluent properties. At a contact time of 15 min and a current density of 5.5 mA/cm2, led to a bacterial killing effectiveness of 97.7% or above. As the current density and contact time increased, a general increase occurred in the bacterial killing efficiency, and the effect of the two above-mentioned factors was much greater than the effect of salinity. Moreover, according to the experimental data, the removal efficiency of chemical oxygen demand (COD) and total suspended solids (TSS) by the aluminum electrodes were 78.50% and 99.93%, respectively. The findings indicate the applicability of the proposed electrochemical treatment to wastewater effluent. Nevertheless, to be able to apply this system at an industrial scale in the future, it is necessary to conduct more research into the optimum operation conditions and make an in-depth comparison of energy consumptions between the electrochemical treatment and the conventional approaches. [ABSTRACT FROM AUTHOR]

The objective of this work was to study the effect of hydraulic retention time on the removal efficiency of the chemical oxygen demand (COD), and to evaluate the energy consumption (EC) using the electrocoagulation process in continuous mode with aluminum and iron electrodes. Three volumetric flows of 10, 15 and 22.5 L/h, with hydraulic retention times of 0.5, 0.33 and 0.22 h were studied. The COD and turbidity ranges were 5,400-9,500 mg/L and 2,000-2,600 NTU, respectively. Experimental data were analyzed using kinetic equations: pseudo-first-order and pseudo-second-order models considering both isothermal and non-isothermal conditions. Under optimal conditions, voltage 8 V and hydraulic retention time of 0.33 h, the COD and turbidity removal efficiencies were 62.2% and 99.5%, and 51.2% and 94.5% with aluminum and iron electrodes in a time 60 min, respectively. The results showed that the data fit the pseudo-second-order isotherm model (R² = 0.997-1.000). The study showed that the EC process strongly depends on hydraulic retention time. [ABSTRACT FROM AUTHOR]

Accurate and fast breath monitoring is of great importance for various healthcare applications, for example, medical diagnoses, studying sleep apnea, and early detection of physiological disorders. Devices meant for such applications tend to be uncomfortable for the subject (patient) and pricey. Therefore, there is a need for a cost-effective, lightweight, small-dimensional, and non-invasive device whose presence does not interfere with the observed signals. This paper reports on the fabrication of a highly sensitive human respiratory sensor based on silicon nanowires (SiNWs) fabricated by a top-down method of metal-assisted chemical-etching (MACE). Besides other important factors, reducing the final cost of the sensor is of paramount importance. One of the factors that increases the final price of the sensors is using gold (Au) electrodes. Herein, we investigate the sensor's response using aluminum (Al) electrodes as a cost-effective alternative, considering the fact that the electrode's work function is crucial in electronic device design, impacting device electronic properties and electron transport efficiency at the electrode–semiconductor interface. Therefore a comparison is made between SiNWs breath sensors made from both p-type and n-type silicon to investigate the effect of the dopant and electrode type on the SiNWs respiratory sensing functionality. A distinct directional variation was observed in the sample's response with Au and Al electrodes. Finally, performing a qualitative study revealed that the electrical resistance across the SiNWs renders greater sensitivity to breath than to dry air pressure. No definitive research demonstrating the mechanism behind these effects exists, thus prompting our study to investigate the underlying process. [ABSTRACT FROM AUTHOR]

The aim of the present work was to provide a viable and active way to remove COD and colour from landfill leachate treated by adopting combined process of electrocoagulation and solar photo Fenton process. Coagulating agents such as metal hydroxides are created by the electrolysis process through self-sacrificial electrodes. Aluminium and iron dissolves at the anode and hydrogen gas are generated at the cathode when aluminium and iron electrodes are utilised. The contaminants interact with the coagulating agent to generate enormous organic flocs. The leachate was obtained from a landfill in Madurai and then it was characterised in terms of its major predominant pollutants. In this study, the electrocoagulation process was used in conjunction with the solar photo Fenton process to treat the leachate under ideal conditions of pH = 7, NaCl = 2 g/L, voltage = 4 V, Al & Fe electrodes and inter electrode distance = 3 cm with a COD and colour removal effectiveness of 75% and 76%, respectively. Furthermore, the effluent from the electrocoagulation process was treated using a solar photo Fenton process at pH = 3, H2O2 = 10 g/L and Fe2+ = 1 g/L with COD and colour reduction effectiveness of 90% and 91%, respectively. In this combination of treatment systems, leachate biodegradability increased from 0.35 to 0.73, favouring the biological oxidation process in conventional treatment plants. This research demonstrates that employing this paired electrocoagulation–solar photo Fenton to treat landfill leachate can achieve consistent treatment effects with high removal efficiencies, and that it is an acceptable treatment technique for landfill leachate. [ABSTRACT FROM AUTHOR]

In this study, the effects of the pH of tannery wastewater obtained from a local leather processing factory on the removal of COD and turbidity, and cost of theelectrocoagulation process was investigated. Studies were carried out under two different operatingconditions. The highest COD removal efficiency was obtained as 83.5% when the initial pH was set to 3, while the energy consumption at this pH was found to be 3.88 kwh m−3. In studies where pH was kept constant, the highest removal efficiency obtained was 83.33% at pH = 5. In this case, the energy consumption was determined as 2.44 kWh m−3. The total cost of the system was calculated as 1.0899 $ m−3 under controlled pH conditions and 0.8761 $ m−3with uncontrolled pH. Studies show that the COD removal kinetics are more suited to 2nd degree kinetics. The highest removal rate for uncontrolled pH was k2 = 0.0791 L g−1 min−1 at pH = 3. The highest rate for controlled pH was k2 = 0.0397 L g−1 min−1 at pH = 5. [ABSTRACT FROM AUTHOR]

Petroleum refineries widely use γ-Al2O3 in multiphase reactors as a catalyst support material. The techniques used to synthesize this support are usually expensive and complicated. In the present study, high-purity nano-γ-Al2O3 was produced from aluminum waste (scrap) for the first time, using a novel eco-friendly electrolysis method. A special electrical cell consisting of two aluminum electrodes was designed and manufactured for this electrolysis process. The electrochemical reactions in the cell were managed by an efficient control system. The X-ray diffraction (XRD) results indicated that the structure of the prepared nano-γ-Al2O3 was highly crystalline with high purity. The total surface area and pore size of the synthesized nano-γ-Al2O3 were 219 m2/g and 0.316 cm2/g, respectively. The prepared nano-alumina in this work can be used successfully as a catalyst support for petroleum industry applications. Additionally, the electrolysis method is characterized by high economic feasibility with a production rate of 91.7% and the yield of produced nano-γ-Al2O3 was (0.053 g/cm h). Finally, this method is regarded as highly flexible, simple, and eco-friendly synthesis. [ABSTRACT FROM AUTHOR]

Electrocoagulation technique using aluminum electrodes in a batch bi-polar system was investigated to determine the efficiency of removing oil from oily wastewater. The Box–Behnken design was utilized to optimize conditions and the effects of four independent factors, including oil volume (X1), temperature (X2), initial pH (X3), and treatment time (X4),—were examined to investigate turbidity recovery and conductivity changes. The significant independent variables and their interactions were assessed using ANOVA. The optimal operating conditions for turbidity removal were obtained at an oil volume of 10 ml L−1, a temperature of 28 °C, an initial pH of 4, and a coagulation time of 90 min. The results revealed that turbidity removal and conductivity changes are enhanced significantly with increasing treatment time and decreasing oil volume. The application of the treatment process under optimal operating conditions allows promising removal efficiencies of 97.3%, and 73.4% for turbidity and conductivity, respectively. Also, the treated wastewater showed remarkable changes in removal efficiencies of the main oily wastewater pollution loads for COD, NO2, PO4, DO, and BOD. The economic study indicated that oily wastewater treatment by electrocoagulation is a very cost-effective technique. [ABSTRACT FROM AUTHOR]

Textile production is one of the largest sectors in the manufacturing industry; however, the textile dyeing process produces a voluminous amount of highly colored wastewater. The dyes used are organic compounds of different dye classes that are stable in an aquatic environment with low decomposition rates. This study investigated the removal efficiency of five textile dyes of different dye classes (Disperse Orange 30, Acid Blue 324, Basic Yellow 28, Reactive Black 5, Vat Brown 1) from wastewater by electrocoagulation (EC) process that was equipped with aluminum electrodes. EC process achieved 91.98, 98.13, 47.46, 92.55, and 82.60% removal efficiencies for AB324, BY28, VBI, and RB5, respectively, at a current density of 0.83 mA/cm2. The energy consumption for dyestuff removal was in the following order: DO30 < VB1 < RB5 < AB324 < BY28. The total operating cost per kilogram of dyestuff removed in 15 min at 0.0502 mA/cm2 was determined as 0.250, 0.274, 0.550, 0.647, and 0.764 $/kg for DO30, VB1, RB5, AB324, and BY28, respectively. The removal mechanism was well fitted to the pseudo-first-order kinetic model with R2 above 0.94 for AB324, BY28, and RB5 dyes. However, the removals for DO30 and VBI dyes were exponential and neither fitted the first-order kinetic nor second-order kinetic model. The overall removal trend was as follows: DO30 > VB1 > AB324 > RB5 > BY28. Therefore, the use of dyes that can easily be removed from wastewater should be encouraged to preserve the quality of water in the receiving environments and to reduce the cost of wastewater treatment. [ABSTRACT FROM AUTHOR]