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Energy storage technologies play a crucial role in addressing the intermittent characteristics of renewable energy sources, improving the stability of electrical grids, and decreasing the release of greenhouse gas emissions. In this study, we presented nickel indium oxalate (Ni 1-x In x C 2 O 4) as a promising material with potential applications in the field of electrochemical energy storage. The as-prepared Ni-In- oxalate sample was subjected to different physical characterizations, including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Regarding the electrochemical energy storage capability, the Ni 1-x In x C 2 O 4 electrode material exhibited a specific capacitance of 835 F g−1 (417.5 C g−1) at 1 A g−1. The incorporation of nickel (Ni) into the indium (In) oxalate nanoplates enhances their electrochemical performance. The presence of Ni in the nanoplates generated from substrate, improving the overall conductivity of the material and enhances its electrochemical reactions, thus leading to improved energy storage capabilities. [ABSTRACT FROM AUTHOR]

The consumption of the Pt electrocatalyst, which occurs when aqueous solution with neutral pH is electrolyzed with a Pt electrode to produce hydrogen or oxygen, was measured from the change in resonance frequency using the QCM method. First, it was found that the Pt consumption from the electrode during water electrolysis while applying a steady positive potential was very small, but it was almost proportional to the time the current was applied. Second, when electrolysis was performed by polarity reversal electrolysis of the anode and cathode periodically during electrolysis, the amount of Pt consumed increased in proportion to the number of polarity reversal was exchanged. The Pt consumption obtained by the QCM method was in close agreement with the value obtained by EDX method, proving the validity of the measurement method. The QCM measurement method was also proven to be a reliable method of measurement. • Constant-current water electrolysis, Pt anode consumed slightly with time. • Polarity reversals water electrolysis, Pt consumed increases with number of times. • Chloride ion concentration affects Pt electrode consumption in a nonlinear manner. [ABSTRACT FROM AUTHOR]

The hydrogen (H 2) and oxygen (O 2) generation from water has garnered great attention in the field of energy worldwide. Thus, the fabrication of durable, scalable, and efficient electrodes for electrocatalysis is a challenge perceived by most researchers around the globe. The current investigation presents the construction of a highly active, binder-free, and scalable nickel-iron cobalt oxide (NFCO) electrode on a Flexible Stainless Steel Mesh Substrate (FSSM) using the reflux condensation deposition method. Interestingly, the as-prepared electrode (NFCO@FSSM) exhibited a very low overpotential of 260 mV at 10 mA cm−2 which outperformed the previously reported nickel and cobalt-based electrodes. The practical applicability was investigated by characterizing the NFCO@FSSM electrode after a 200 h durability study. The NFCO@FSSM electrode (anode) with FSSM electrode (cathode) could generate 34.6 L O 2 over 200 h using a prototype electrolysis setup. This is ascribed to the high electrochemical active sites, multiple oxidation states, and rapid electron transfer. This work provides a new perspective on introducing iron in nickel and cobalt-based electrodes to produce economic and scalable electrodes for efficient oxygen evolution reaction (OER). Development of sustainable, highly active, scalable, and binder-free NFCO@FSSM electrode for the bulk production of O 2. [Display omitted] • Scalable and binder-free synthesis of nickel-iron-cobalt-oxide electrode. • The electrode exhibits a low overpotential of 260 mV@10 mA cm−2. • The synergistic effect of Ni, Fe, and Co presented improved electrocatalytic activity. • XPS analysis revealed the transfer of electrons from Fe to Co to Ni. • The scale-up device shows 34.6 L of oxygen evolution in 200 h. [ABSTRACT FROM AUTHOR]

Piezoelectric ceramics with high electro strain are widely used in actuators, sensors, and so on. Here, this work investigates the electro strain of representative piezoelectric materials, and analyzes the influence of electrode type on the electro strain of PZT41 with significant strain anomalies. It is found that the occurrence of abnormally significant strain is not affected by the electrode but caused by intrinsic defects. Therefore, the ceramic samples with and without defects tailoring in Na 0.5 Bi 0.5 TiO 3 (NBT) based and PbZr 0.52 Ti 0.48 O 3 (PZT) based systems were prepared by the solid-state reaction method, and the results show that abnormally ultrahigh electro strains occur in excessively thin samples with diploes due to defects tailoring. Through displacement configuration experiments and comprehensive analysis of polarization switching processes, it is found that the occurrence of asymmetric abnormal significant strains is caused by reversible bending deformation in excessively thin samples. This work provides new support for the emergence of ultrahigh electro strain in piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Symmetric solid oxide fuel cells (SSOFCs) are attracting much attention due to their ability to improve chemical and thermal compatibility between electrolytes and electrodes and reduce manufacturing costs. The in-situ precipitating of electrode in reduction atmosphere has been proved to be an effective strategy to improve the maximum power density of SSOFCs. Herein, we use the Li(Ni x Co 2/3-x Mn 1/3)O 2 (LNCM) serial material as the symmetrical electrodes to fabricate SSOFCs, which are operated in normal and reverse mode. In reverse operation, the LNCM is firstly reduced by hydrogen and in-situ precipitates the Ni–Co alloy and Li 2 MnO 3. The electrochemical impedance spectra (EIS) indicates that the reduced product delivers excellent oxygen reducing activity as well as promising catalytic activity toward hydrogen oxidation reaction. Thus, the SSOFCs based on LNCM symmetric electrodes present superior electrochemical performance in the reverse operation. Moreover, in the LNCM serial samples, the atomic ratio of Ni and Co at the B site is adjusted to control the contents of in-situ precipitation for further optimizing the cell performance. Using Li[Ni 1/2 Co 1/6 Mn 1/3 ]O 2 as symmetric electrodes shows outstanding performance of 923 mW cm−2 at 550 °C. This work provides a reference scheme for electrode design of SSOFCs. [ABSTRACT FROM AUTHOR]

• Preparation of biochar from textile sludge based industrial waste. • Pyrolysis of biochar at 900 °C in inert environment to convert into activated carbon. • Nano-modification of activated carbon by optimal loading of reduced graphene oxide. • Evaluation of rGO@AC-900 °C composite as electrode material for supercapacitor. • rGO@AC-900 °C as electrode shows high capacitance with enhanced cyclic stability. The procedure for disposing of textile waste sludge requires sustainable solutions due to numerous environmental issues associated with its disposal. The majority of textile manufacturers incinerate the waste sludge to meet their heating demands, which is harmful to the environment. It can also be used in soil amendment, biodegradable products, construction material and water treatment process as absorbent to remove the heavy metals etc. In this study we use the heavy metal containing textile waste sludge as a precursor for the fabrication of functional electrode material for supercapacitor applications. In this process the organic content within the textile sludge waste is treated at 900 °C and transformed into activated carbon, a vital component of supercapacitors electrodes. Through a series of pyrolysis and activation processes, it is further converted into porous activated carbon (AC) with a wide surface area and appropriate electrochemical properties. To enhance the overall conductivity of the electrode material for supercapacitor applications, the carbon content of the material is increased by loading of reduced graphene oxide (rGO) up to 4 wt%. It resulted in a significant increase in the surface area up to 128.68 m2/g. The effective conversion and relevance of the obtained material for supercapacitor applications is further reinforced by the excellent electrochemical performance of rGO@AC-900 °C which generated a specific capacitance of 362F/g with 4 wt% loading which is higher than the specific capacity achieved with lower rGO loading i.e., 83.2 F/g and 182.5 F/g for AC-900 °C and 2 wt% rGO@AC-900 °C, respectively. The 4 wt% rGO@AC900°C also represented improved stability with up to 82 % charge retention after 5000 charge–discharge cycles. The excellent EDLC behavior of 4 wt% rGO@AC900°C is also evident from the impedance data. The electrode material with 4 wt% rGO loading showed lower value of R CT i.e., 4.16 Ω as compared to 12.08 Ω with 2 wt% rGO loading. This novel approach offers a sustainable alternative for the handling of hazardous textile waste sludge through conversion into a potential electrode material for environmentally friendly energy storage devices. [ABSTRACT FROM AUTHOR]

Symmetric solid oxide cells (SSOCs) have attracted much attention due to their high energy conversion efficiency and simple manufacturing. The present study involves the synthesis of a class of double perovskite oxides, which serve as electrodes for SSOCs. These oxides exhibit exceptional stability in an oxidizing atmosphere, maintaining their single-phase double perovskite structure. Moreover, they facilitate the co-exsolution of metal nanoparticles from both A and B-sites under reducing conditions. By optimizing the doping amount of Bi in Sr 2- x Bi x FeTiO 6− δ (SB x FT), co-exsolved Bi and Fe nanoparticles decorated double perovskite oxides were obtained in reducing atmosphere and employed as high-performance electrodes for SSOCs. With Sr 1.2 Bi 0.8 FeTiO 6-δ as the electrode, the maximum power density achieves 537 mW cm−2 at 850 °C. In electrolysis mode, the current density for pure CO 2 electrolysis reaches 1.43 A cm−2 at an applied voltage of 1.5 V and 850 °C. All of these results indicate that co-exsolution of components on perovskite is an effective design technique for creating materials with desirable features. [Display omitted] • The novel co-exsolved metal nanoparticles decorated double perovskite oxides were obtained by Bi doping. • The Sr 2- x Bi x FeTiO 6 - δ were as the electrodes for symmetric solid oxide cells. • In SOFC mode, SB 0.8 FT exhibits excellent electrochemical performance. • In SOEC mode, SB 0.8 FT shows excellent CO 2 reduction properties and stability. [ABSTRACT FROM AUTHOR]

Cobalt selenide (CoSe 2) emerges as a highly promising anode material for lithium-ion batteries (LIBs) owing to its high theoretical capacity and cost-effectiveness. Despite these merits, its practical utilization faces challenges stemming from substantial volume fluctuations and limited electronic conductivity. To tackle these issues, a plum-branch-like structure of CoSe 2 @N-doped carbon that embedded in one-dimensional N -doped carbon fibers (CoSe 2 @NC/CFs), is successfully synthesized through an in-situ confinement method. Well-defined CoSe 2 @NC nanoparticles, featuring diameters between 20∼30 ​nm, are uniformly dispersed on both the inner and outer surfaces of the carbon fibers. The distinctive architecture of CoSe 2 @NC/CFs ensures an increased number of active sites, elevated electronic conductivity, alleviated volume expansion, and accelerated reaction kinetics. Consequently, the CoSe 2 @NC/CFs exhibits remarkable cycling performance and exceptional rate capability. Operating at a current density of 1000 ​mA ​g−1, the CoSe 2 @NC/CFs anode sustains a capacity of 664 ​mA ​h ​g−1 with no obvious capacity decay over 500 cycles. Even at a high current density of 5000 ​mA ​g−1, it maintains a capacity of 445 ​mA ​h g−1 with a mere 0.02 ​% capacity decay per cycle. This study introduces a novel approach to anode material design, showcasing significant advancements in lithium-ion battery technology. [Display omitted] • CoSe 2 @NC/CFs with a bilayer N -doped carbon were synthesized via spatially confinement and a bridge mindset. • CoSe 2 @NC/CFs has more active sites, weaken volume expansion and fast Li+/e− transmission. • It demonstrates a capacity of 664 ​mA ​h g−1 after 500 cycles with no attenuation at 1 ​A g−1. • Even ​at 5 ​A ​g−1, the capacity remains 380 ​mA ​h ​g−1 ​after 700 cycles with a decay rate of 0.02 ​% per cycle. [ABSTRACT FROM AUTHOR]

[Display omitted] Realizing an electrode that can stably monitor biosignals after multiple exposures to sweat is challenging. Utilizing a Janus electrode, which is composed of a stack of ultrathin hydrophobic microporous Au membrane and water-durable hydrophilic nanofiber layers, asymmetric wettability can be realized and maintained for 7 days. Thus, it can create spontaneous unidirectional sweat transport from the skin surface, ensuring that the skin-electrode interface remains dry, especially during sweating. The ultrathin hydrophobic membrane facilitates self-adhesion with an adhesion energy of 59.2 µJ cm−2, which creates a high conformal contact to the skin and self-adhering to the hydrophilic nanofibers. The hydrophilic nanofibers exhibit excellent durability even after continuous immersion in water for up to 1 month. Additionally, a thin translucent polyvinyl alcohol nanofibers frame assists the Janus electrode in achieving highly conformable attachment to both dry and sweaty skin. The Janus electrode also exhibits excellent breathability and high mechanical stability owing to its porous structure and fine thickness. With these properties, the Janus electrode can monitor an electrocardiogram signal after dynamic activities, including physical exercise, waking up, desk work, meals, and going out for 6 days, while maintaining a stable signal-to-noise ratio of ∼ 18.8 dB. [ABSTRACT FROM AUTHOR]

The paper presents an original method for synthesizing high-density composite ceramics with a Mo 2 C/Mo 3 Co 3 C composition using the technology of high-speed Spark Plasma Sintering (SPS) of a mechanically activated powder mixture of Mo 2 C-10 wt%Co. The activated homogeneous starting mixture was obtained by wet milling/activation of the initial powders of Mo 2 C and Co in an anhydrous isopropanol medium. The ceramic samples were consolidated by SPS under vacuum (10−5 atm.) at 1000, 1100, 1150, and 1200 °C with a heating rate of 87.3 °C·min−1 under constant external uniaxial pressing pressure of 50 MPa. The sintering kinetics were studied, the twofold nature of sintering was established, and the temperature range of active densification was determined. The ceramic synthesis is accompanied by a reactive interaction of the components, resulting in the formation of the Mo 3 Co 3 C phase and a change in the crystal lattice of the non-stoichiometric Mo 2 C x compound. The ceramic obtained in the temperature interval of the isothermal sintering stage of 1150–1200 °C is homogeneous in the distribution of Mo and Co, consists of a Mo 2 C/Mo 3 Co 3 C phase mixture, has a density value of 98.13 ± 0.5 % theoretical density, and has an average Vickers hardness value of ∼1526 HV. Increasing the sintering temperature to 1200 °C results in the formation of almost monolithic structures in the samples, but also induces the formation of large defects due to the collective consolidation of pores within the bulk material and increases the susceptibility of the ceramic to cracking. The paper presents preliminary results from electrochemical testing. The proposed method for synthesizing Mo 2 C/Mo 3 Co 3 C ceramics has potential for use in optimizing the composition and production methods of electrode materials for the realization of active components in heterostructured electrodes used for hydrogen evolution. [ABSTRACT FROM AUTHOR]

The performance of an electrochemical energy storage device highly depends on the electrode material. Currently, metal oxalates are evolving as low-cost and stable electrode materials for batteries and supercapacitors. Herein, mixed metal oxalate (Ni x Co 1-x C 2 O 4 /NF) based binder-free electrode was fabricated. The nickel foam contributed not only as a substrate but also as a nickel source. The Ni x Co 1-x C 2 O 4 /NF confirmed the crystalline phase through X-ray diffraction spectroscopy (XRD). Scanning electron microscopy (SEM) and transmission electron spectroscopy (TEM) confirmed the integrated 1D/2D-like morphology of Ni x Co 1-x C 2 O 4 /NF. The electrochemical results reveled the Ni x Co 1-x C 2 O 4 /NF electrode exhibit battery behavior with capacity retention of 86.58 % and possessed the highest specific capacity of 470.012 C g−1 at 1 A g-1. Hence, the nickel inclusion during the synthesis has further enhanced the overall properties and performance of the Ni x Co 1-x C 2 O 4 /NF electrode. [ABSTRACT FROM AUTHOR]

In this present work, we have investigated the performance of two kinds of electrolyzers: Proton exchange membrane (PEM) and Alkaline water electrolyzers (AWE), which are powered by a photovoltaic (PV) system. The results showed that PEM needs less voltage than Alkaline to produce the same amount of hydrogen. For the Alkaline electrolyzer, two types of solutions have been used as an electrolyte: Potassium Hydroxide (KOH) and saline water. Experimental tests revealed that the optimal concentration ratio to achieve the best flow rate of hydrogen corresponds to 100 % seawater. The best production of hydrogen, using the Alkaline electrolyzer, has been found with KOH as the electrolyte. In fact, the accumulated quantities of hydrogen produced, during the same experiment time of 10 h, are 10300 ml/day if using PEM electrolyzer, 3600 ml/day and 450 ml/day if using alkaline with the KOH solution and sea water, respectively. So, it requires to use almost 8 units of sea water as an electrolyte to get the same daily hydrogen production if using KOH solution as electrolyte. It is observed that the hydrogen production increases with the increase of the incident solar irradiation. Also, the system (PV-PEM) has higher efficiency than the system (PV-Alkaline) and the total system efficiency decreases from 15 % to 8 % with the increase of incident solar irradiation. The results indicated that the higher production of hydrogen is obtained by using aluminum electrodes than copper or stainless-steel electrodes. • Experimental water electrolyzer polarization curves are conducted for AWE and PEM. • Effect of seawater, as electrolyte, on the daily hydrogen flow rate production. • Effect of a PV system with MPPT on the daily hydrogen flow rate production. • Effect of electrodes types on the daily hydrogen flow rate production. [ABSTRACT FROM AUTHOR]

A novel layered double perovskite-based electrode of composition Ba 2 NiMoO 6-δ (BNMO) is proposed for application in Protonic Ceramic Electrochemical Cells (PCECs). Structural characterization by X-ray diffraction (XRD) revealed good chemical compatibility with a BaCe 0.7 Zr 0.1 Y 0.2 O 3- δ (BCZY712) electrolyte and phase stability in oxidizing atmospheres. In this study, symmetrical cells of both the pure BNMO electrode and a composite electrode with 50 vol% of BCZY712 material were prepared by screen printing and sintering in air at 950 °C. Microstructural characterization by Scanning Electron Microscopy (SEM) showed good adhesion of the electrode films with the substrate, while Energy-dispersive Spectroscopy (EDS) revealed good percolation of both phases in the case of the composite electrode. Electrochemical studies made by Electrochemical Impedance Spectroscopy (EIS) on the pure BNMO electrode demonstrated that the total polarization resistance was lower in wet conditions in the case of N 2 atmospheres, corroborating a potential protonic contribution, while in O 2 atmospheres this term was similar between wet and dry conditions, due to dominant p-type electronic conductivity. Conversely, performance was aggravated by the addition of the BCZY712 composite phase; a result clarified to be due to an insufficient level of electronic conductivity in the composite electrode. To the best of our knowledge this is the first study of BNMO for proton conducting applications, providing important information on preparation, compatibility and electrochemical performance, as required for its further optimization. • Pure Ba 2 NiMoO 6-δ (BNMO) and composite BNMO + BaCe 0.7 Zr 0.1 Y 0.2 O 3- δ (BCZY712) electrodes are fabricated. • BCZY712 and BNMO mixtures shown to be chemically stable up to 1100 °C in air and with suitable thermal expansion match. • R p of pure BNMO electrode shows water vapor pressure dependence in N 2 , corroborating a potential protonic contribution. • Comparison between BNMO and composite electrodes revealed electronic transport as the key property for further improvement. [ABSTRACT FROM AUTHOR]

With the growing need for soft robots and wearable electronics, batteries play a crucial role, but finding high-performance electrode materials is still difficult. Recently, heterostructures (HS) have been effectively developed, and it has been discovered that they perform superbly as electrodes/anodes and for metal ion batteries (MIBs). However, the mechanism behind the promising experimental outcomes is not fully understood. This study shows that MoS 2 /Ti 3 CO 2 HS is an attractive and competitive anode/electrode material for Li+/Na+/K+-ions batteries. The HS system shows enhanced electrical conductivities compared to MoS 2 and Ti 3 CO 2 single-layers. The calculated adsorption energies (E ads) prove the admirable higher negative values for Li+ compared to the Na+/K+-ions. Due to the lower diffusion energy barrier of Li+-ion than the Na+/K+-ions, it can be concluded that MoS 2 /Ti 3 CO 2 HS is a promising anode/electrode material for Li+-ion batteries. The results discussed above shed light on the experimental configuration of the HS-based electrode/anode material for MIBs. [ABSTRACT FROM AUTHOR]

Oximetry, capnography and pH measurement are a fundamental facet of safe and modern anaesthetic and intensive care practice. A good anaesthetist will not only use these techniques routinely but will also understand how they work and how this can affect clinical management of their patients. This educational article aims to demonstrate the principles underlying these techniques, their limitations and recent developments. [ABSTRACT FROM AUTHOR]

In this work, ammonia electrooxidation (AEO) is studied to probe the electrochemical behavior of aqueous NH 3 as direct fuel by implication of gamma alumina supported copper oxide catalysts (CuO/Al 2 O 3). Precipitation and impregnation techniques are adapted to synthesize the substrate Al 2 O 3 , and loading of different ratios (1%, 2%, 3%, 4%) of active precursor i.e., CuO, respectively. Small average crystallite sizes (D Avg) in range of 1.46–6.76 nm and smaller particle sizes from micrographs proposed a superb activity of the catalysts. Modified GCE exhibited the excellent conductive properties towards standard redox probe K 4 [Fe(CN) 6 ] and KCl, displaying a high active electrochemical surface area of up to 0.0021 cm2. Current profiles in response to increase in scan rates, concentrations of ammonia and temperature have been observed in 0.1 M KOH, thereby estimating the thermodynamic and kinetic constraints of the AEO process. Attributed to the electroactive properties towards AEO, CuO/Al 2 O 3 is found to exhibit the desirable physiochemical properties owing to large oxidation current, large diffusion coefficient "D°" (3.6 × 10-9 cm2 s-1), large rate constant "ko" (1.2 × 10-5 cm s-1), large system entropy "ΔS" (-108 J K-1 mol-1), high change in enthalpy "ΔH" (72.3 J mol-1) and low activation energy "ΔG" (32.8 kJ mol-1). Resultingly, the oxidation of ammonia is found to be facile and robust by incorporation of CuO/Al 2 O 3 catalysts owing to large ko, ΔH and ΔH. This study opened a gateway towards eco-benign and economical efficient energy generation and viable market entry of direct ammonia fuel cells. • CuO/Al 2 O 3 microstructures are developed by typical precipitation and impregnation techniques. • Electrochemical understanding is built after fabricating the GCE with CuO/Al 2 O 3 catalysts. • Modified electrodes are tested for electrooxidation of ammonia in 0.1 M KOH electrolyte. • Kinetic and thermodynamic parameters are estimated varying the analyte concentration and temperature, respectively. • AEO is diffusion-controlled at low temperatures while activation-controlled at higher temperatures. [ABSTRACT FROM AUTHOR]

As an excellent source of sustainable green energy, solid oxide fuel cells (SOFCs) become a compelling energy conversion and storage device which has been attractive to stakeholders worldwide for their high fuel efficiency, lower air pollution, reduced cost, and admirable steadiness. The electrodes, anode, and cathode, are the significant components of SOFC, facilitate byproducts transportation via electrochemical reaction, and fuel oxidation with electron and ion transportation. SOFCs with a lower operating temperature will reduce system and operating costs while increasing long-term durability. The performance of electrodes in SOFCs has been developed and investigated using a variety of material compositions, as the key determinant of efficiency is dependent on lower operating temperatures. Nanostructured materials, in particular, have demonstrated the greatest potential for improving electrodes at low operating temperatures by enhancing the surface area and improving electrocatalytic activity. Artificial intelligence (AI) is used to create the theoretical SOFC model to minimize the time necessary to identify the operational optimum over a wide range of parameters as well as the total cost of the system. In this review, we have highlighted the development of nanostructured electrodes, their preparation techniques, and the function of AI in the creation of a range of nanoelectrodes and SOFC modeling as well as their significant roles in improving SOFC performance. • The focus on nanomaterial research is significant for developing solid oxide fuel cells. • Low-temperature functioning of SOFCs is aided extra benefits in nanomaterials. • Economical solutions of fabrication and performance of nanomaterials for SOFCs. • The potential of artificial intelligence (AI) is a promising wing in nanomaterials fabrications. • One of the most promising simulation models for SOFCs is artificial neural networks (ANN). [ABSTRACT FROM AUTHOR]

Sewage sludge as a byproduct of industrial and municipal wastewaters treatment is produced worldwide at large quantities. This organic waste contains nutrients, pathogens, heavy metals, organic pollutants and other toxic substances. In recent years, the significant increase in the amount of sludge as an important environmental issue, which is considered both a threat and an opportunity, has highlighted the issue of its proper management. In recent decades, various methods have been used to manage and energy recovery from sewage sludge, including pyrolysis, incineration, gasification, anaerobic digestion, aerobic digestion, landfill, composting, lime and microbial fuel cell. Nowadays bioenergy production from sewage sludge attracted the attention of environmentalists due to environmental and economic considerations. In this regard, microbial fuel cells (MFCs) have gained a great importance as an alternative energy conversion method for bioenergy production. This system converts the chemical energy in the organic substance directly into valuable electrical energy by the catalytic reaction of microorganisms. The effectiveness of the system depends on the reactor configuration, operational and environmental parameters. Identifying and optimizing these parameters are important to increase the system efficiency. In this paper, we reviewed and discussed the effects of different parameters on the treatment and electricity generation from waste activated sludge (WAS) using MFC system such as nature of electrode materials, oxygen flow rate, reactor design, substrates and pH. Furthermore, a better understanding of the MFCs performance for bio-fuel generation from WAS, as well as solving concerns associated to the abilities of this technology in real application is aims of this review. [Display omitted] • To power generation and sewage sludge stabilization, simultaneously. • Impact of configurations and operation of MFC on sewage sludge stabilization. • To study the factors influencing the sewage sludge treatment and power generation by MFC. [ABSTRACT FROM AUTHOR]

Materials engineering is an important trajectory for the design of new complex oxide compounds for their high-temperature application in solid oxide electrochemical cells. Usually, tailoring the functional properties of such compounds is realized through a cationic-type doping strategy, when a partial substitution of basic cations with impurity ions is performed. Typically, such a doping improves some properties, but deteriorates others due to significant changes in the cationic framework of a crystal. Anionic-type doping is an alternative way to leave the cationic sites unchanged, which may be suitable for achieving a compromise between a variety of properties. In this brief review, we summarize the existing data devoted to the F-doping (or F-insertion) of solid oxide electrolyte and electrode materials. In most cases, the F-doping improves the chemical stability of compounds and their ionic transport properties. Possible reasons responsible for this improvement are briefly discussed. In addition to highlighting these advantages, possible drawbacks are also listed to stimulate further research activities on this problem. [Display omitted] • This work overviews a strategy of F-doping of solid oxide materials (SOMs). • The insertion of small amounts of fluorine improves the ionic conductivity of SOMs. • The chemical stability against CO 2 is also often higher for F-containing SOMs. • The F-doped SOMs can be used as SOFC/SOEC electrolytes and electrodes. [ABSTRACT FROM AUTHOR]

Despite the rapid scale-up of battery production which could be observed the last years, various challenges remain in electrode production. In particular, the high scrap rates of up to 40 % during the coating process of the electrodes offer enormous potential in terms of economic and ecological aspects. To counter these problems, a system concept was developed that can react autonomously to process conditions and thus reduce scrap. For this purpose, with the gap distance and the angle of attack deliberately two parameters are varied during slot-die coating, which react quickly and furthermore do not affect the productivity of the system. By adapting the position of the slot-die, it is possible to achieve an optimum operating point in the coating window and thus improve the quality of the results without regulating the volume flow or the web speed. The aim is both to shorten the start-up process by a fast and precise correction of the slot-die position on the basis of the coating result and to increase the quality in the adjusted operation. With the help of the corresponding measuring technology and the control based on the coating result, the processing of slurries with fluctuating fluid properties or the processing of new recipes is simplified and possible without manual intervention. The concept is possible for existing plants as well as for new plants. [ABSTRACT FROM AUTHOR]

The resistive switching (RS) behavior of multilayered ReRAM devices is typically influenced by two aspects: the intrinsic properties of the dielectric multilayer, and other extrinsic contributions. In this study, we deposited and investigated bi-layered memories incorporating ZnO and HfO 2 dielectrics. Different stacking sequences of the two oxides (ZnO/HfO 2 and HfO 2 /ZnO) were employed to explore the intrinsic contribution of the bilayer microstructure, while different top electrode configurations (Pt and Ti) were utilized to demonstrate the extrinsic impact. All devices exhibit characteristic bipolar RS behavior, showcasing their functionality. But interestingly, the device with a Pt top electrode displays digital RS behavior, while the one with a Ti top electrode exhibits analog RS behavior. The completely different switching types observed during the reset process of the ZnO-HfO 2 hybrid resistive memories are attributed to different interface charge migration process and structural characteristic. And as compared to the tailoring effect of stacking sequences (bilayer microstructure and oxide/oxide interface), the tailoring effect of top electrode configuration (electrode materials and oxide/electrode interface) is much stronger. Based on the latter, the switching ratio can be remarkably improved by at least two orders of magnitude, the reset voltage (energy consumption) can also be significantly reduced, and other discussed switching parameters can also show greater improvement. The comprehensive comparative analysis of intrinsic and extrinsic contributions provides valuable insights for exploring the RS mechanism and optimizing the design of bi-layered memory devices. [ABSTRACT FROM AUTHOR]

Devices capable of recording or stimulating neuronal signals have created new opportunities to understand normal physiology and treat sources of pathology in the brain. However, it is possible that the tissue response to implanted electrodes may influence the nature of the signals detected or stimulated. In this study, we characterized structural and functional changes in deep layer pyramidal neurons surrounding silicon or polyimide-based electrodes implanted in the motor cortex of rats. Devices were captured in 300 µm-thick tissue slices collected at the 1 or 6 week time point post-implantation, and individual neurons were assessed using a combination of whole-cell electrophysiology and 2-photon imaging. We observed disrupted dendritic arbors and a significant reduction in spine densities in neurons surrounding devices. These effects were accompanied by a decrease in the frequency of spontaneous excitatory post-synaptic currents, a reduction in sag amplitude, an increase in spike frequency adaptation, and an increase in filopodia density. We hypothesize that the effects observed in this study may contribute to the signal loss and instability that often accompany chronically implanted electrodes. Implanted electrodes in the brain can be used to treat sources of pathology and understand normal physiology by recording or stimulating electrical signals generated by local neurons. However, a foreign body response following implantation undermines the performance of these devices. While several studies have investigated the biological mechanisms of device-tissue interactions through histology, transcriptomics, and imaging, our study is the first to directly interrogate effects on the function of neurons surrounding electrodes using single-cell electrophysiology. Additionally, we provide new, detailed assessments of the impacts of electrodes on the dendritic structure and spine morphology of neurons, and we assess effects for both traditional (silicon) and newer polymer electrode materials. These results reveal new potential mechanisms of electrode-tissue interactions. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, the performance of two boron-containing compounds, C14H14BNO2·HCl (BCC1) and C38H38B2Cl2N4O4 (BCC2), as electrodes in supercapacitor applications was investigated in the presence of Na2SO4 and KOH electrolyte solutions. The specific capacitance values of the compounds were compared, and the results showed that trivalent boron (BCC1) exhibited higher specific capacitance values than tetravalent boron (BCC2) in both electrolyte solutions. In the presence of Na2SO4 electrolyte solution, the specific capacitance values of the trivalent (BCC1) and tetravalent (BCC2) boron compounds at a current density of 0.75 A/g were 135.21 and 94.87 F/g, respectively, while in the presence of KOH electrolyte, the specific capacitance values of the trivalent (BCC1) and tetravalent (BCC2) boron compounds at a current density of 0.75 A/g capacitance values were determined as 106.62 and 88.25 F/g, respectively. The cycling stability of the electrodes was also studied, and it was found that the capacitance of BCC1 electrode increased gradually over the cycles, while the capacitance of BCC2 electrode decreased. The study suggests that trivalent boron can be a promising material for supercapacitor applications. However, further research is required to optimize the cycling stability of the electrodes and understand the underlying mechanism. [ABSTRACT FROM AUTHOR]

• In a large monocentric analysis from 452 intracranial explorations, safety of different implantation strategies and electrode types was assessed. • Both, implantations with subdural and depth electrodes had low rates of clinical complications. • Subdural grid electrodes with 64 channels and more had higher rates of symptomatic bleeding than other electrodes. • Signs persisting more than 3 months were rare in either strategy. To analyze the safety profile of subdural and depth electrode implantation in a large monocentric cohort of patients of all ages undergoing intracranial EEG exploration because of drug resistant focal epilepsy diagnosed and implanted by a constant team of epileptologists and neurosurgeons. We retrospectively analyzed data from 452 implantations in 420 patients undergoing invasive presurgical evaluation at the Freiburg Epilepsy Center from 1999 to 2019 (n = 160 subdural electrodes, n = 156 depth electrodes and n = 136 combination of both approaches). Complications were classified as hemorrhage with or without clinical manifestations, infection-associated and other complications. Furthermore, possible risk factors (age, duration of invasive monitoring, number of electrode contacts used) and changes in complication rates during the study period were analyzed. The most frequent complications in both implantation groups were hemorrhages. Subdural electrode explorations caused significantly more symptomatic hemorrhages and required more operative interventions (SDE 9.9%, DE 0.3%, p < 0.05). Hemorrhage risk was higher for grids with 64 contacts than for smaller grids (p < 0.05). The infection rate was very low (0,2%). A transient neurological deficit occurred in 8.8% of all implantations and persisted for at least 3 months in 1.3%. Transient, but not persistent neurological deficits were more common in patients with implanted subdural electrodes than in the depth electrode group. The use of subdural electrodes was associated with a higher risk of hemorrhage and transient neurological symptoms. However persistent deficits were rare with either approach, demonstrating that intracranial investigations using either subdural electrodes or depth electrodes carry acceptable risks in patients with drug-resistant focal epilepsy. [ABSTRACT FROM AUTHOR]

Materials based on barium-containing Pr 2 NiO 4+δ are considered as promising air electrodes for protonic ceramic electrochemical cells owing to a wide range of attractive properties. In the present work, we thoroughly analyze the transport properties of Pr 2 NiO 4+δ upon its chemical modification by Ba-doping. In detail, electrical conductivity and thermo-EMF measurements of Pr 2–x Ba x NiO 4+δ (where x = 0, 0.1, 0.2, and 0.3) allow the effects of charge carrier concentration and mobility on overall transport to be determined depending on the chemical composition and defect structure. Lower polarization resistances of the Ba-containing electrodes when used in symmetrical cells with a BaCe 0.5 Zr 0.3 Y 0.1 Yb 0.1 O 3–δ proton-conducting electrolyte confirm the functional benefits of barium as a dopant. However, the obtained experimental results can be explained not only by the better transport properties of barium-containing Pr 2 NiO 4+δ (shown in the second part of our research), but also by the improved chemical and thermal compatibilities resulting in a good interface quality in an electrolyte/electrode couple (shown in the first part). [Display omitted] • A comprehensive study of the transport properties of the Pr 2–x Ba x NiO 4+δ materials was carried out. • Correlations between composition, defect structure, mobility, and concentration of charge carriers are revealed. • x = 0.2 is the most optimal composition in terms of electrochemical activity. • Improved electrochemical activity relates both to better transport properties and interface quality. [ABSTRACT FROM AUTHOR]

Electrodes for stereotactic electroencephalography (SEEG) are typically fixed to the skull with anchor bolts. When anchor bolts are unavailable, electrodes have to be fixed using other methods, carrying the possibility of electrode shift. This study, therefore, evaluated the characteristics of electrode tip shift during SEEG monitoring in patients with electrodes fixed using the suture technique. We retrospectively included patients who underwent SEEG implantation with suture fixation and evaluated the tip shift distance (TSD) of electrodes. Possible influences evaluated included: 1) implantation period, 2) lobe of entry, 3) unilateral or bilateral implantation, 4) electrode length, 5) skull thickness, and 6) scalp thickness difference. A total of 50 electrodes in 7 patients were evaluated. TSD was 1.4 ± 2.0 mm (mean ± standard deviation). Implantation period was 8.1 ± 2.2 days. Entry lobe was frontal for 28 electrodes and temporal for 22 electrodes. Implantation was bilateral for 25 electrodes and unilateral for 25 electrodes. Electrode length was 45.4 ± 14.3 mm. Skull thickness was 6.0 ± 3.7 mm. Scalp thickness difference was −1.5 ± 2.1 mm, which was found greater in temporal lobe entry compared with frontal lobe entry. According to univariate analyses, neither implantation period nor electrode length correlated with TSD. Multivariate regression analysis showed that only greater scalp thickness difference correlated significantly with greater TSD (P = 0.0018). Greater scalp thickness difference correlated with greater TSD. Surgeons need to consider the degree of scalp thickness difference and electrode shift when using suture fixation, especially with temporal lobe entry. [ABSTRACT FROM AUTHOR]

Polymer Electrolyte Membrane (PEM) fuel cells are a promising source of alternative energy. However, their production is limited by a lack of well-established methods for quality control of their constituent materials like the membrane-electrode assembly during roll-to-roll manufacturing. One potential solution is the implementation of deep learning methods to detect unwanted defects through their detection in scanned images. We explore the detection of defects like scratches, pinholes, and scuffs in a sample dataset of PEM optical images using two deep learning algorithms: Patch Distribution Modeling (PaDiM) for unsupervised anomaly detection and Faster-RCNN for supervised object detection. Both methods achieve scores on performance metrics (ROC-AUC and PRO-AUC for PaDiM and AP for Faster-RCNN) that are comparable to their scores on benchmark datasets. These methods also have the potential to detect a wider range of defects compared to IR thermography and previous optical inspection methods. Overall, deep learning shows promise at detecting relevant defects of interest and has the potential to achieve real-time defect detection. • Deep learning models were used to detect defects in fuel cell electrode images. • Anomaly detection and object detection algorithms were tested. • Deep learning can detect a wider range of defects than previous methods. • Inference times show feasibility of real-time defect detection. [ABSTRACT FROM AUTHOR]

Recent research has focused on the search for new electrode materials to improve the specific capacitance of supercapacitors. Conductive polymers and metal oxides have been extensively tested as electrode materials for supercapacitors. Incorporating both conductive polymers and metal oxides into a composite provides excellent results for the electrochemical performance of supercapacitors. In this present work, we have fabricated the nanoscale α-NiMoO 4 particles that enwrapped on electronically conducting polymer nanocomposites (PNCs) based on Polyvinyl alcohol (PVA)/Poly(vinyl) pyrrolidone (PVP) for supercapacitor applications. The different concentrations of PVA/PVP with α-NiMoO 4 loaded polymer nanocomposites were developed by using a solution casting method. All the polymer nanocomposites have been subjected to Scanning Electron Microscopy (SEM), Fourier Transforms Infrared (FTIR), X-ray diffraction (XRD), and electrochemical studies. The prepared PNCs surface morphology has been acquired as a non-uniform rod-like structure. The electrochemical performances of the prepared PNCs have been investigated and the resultant value of the maximum specific capacitance is 15.56 F g−1 for 1 wt % of α-NiMoO 4 nanoparticles(NPs) loaded polymer blended electrode at a scan rate of 5 mVs−1. The prepared PNCs exhibit 97.12% of columbic efficiency studied by using two electrode systems at room temperature in an aqueous electrolyte solution of 3 M KOH. From these investigation, it has been revealed that the PVA/PVP/α-NiMoO 4 composites could be portable and flexible electrodes for energy storage applications. [Display omitted] • α-NiMoO 4 NPs decorated polymers nanocomposites have been prepared by solution casting technique. • Structural studies of polymer composites have been investigated by XRD, SEM and FTIR spectral analyses. • 1 wt % of α-NiMoO 4 nanoparticles loaded polymer nanocomposite has exhibits 97.12% of columbic efficiency. • Prepared nanocomposites could be portable and flexible electrodes for energy storage applications. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) possess high energy and low power densities, while supercapacitors are characterized by high power and low energy densities. A hybrid PEMFC/supercapacitor device (HPSD) with high energy and power densities was proposed and fabricated for the first time using a reduced graphene oxide/Nafion/Pt electrode in this study. The reduced graphene oxide (rGO) was a capacitive material, and Pt was used as the electrocatalyst. Nafion ionomers adsorbed onto the rGO sheets surface and connected the rGO sheets and the electrolyte (Nafion membrane), thus increasing the utilization rate and specific capacitance of rGO. During the half-cell tests, the rGO/Nafion/Pt electrode exhibited better pulse discharge and galvanostatic discharge performance than the conventional Nafion/Pt electrode. Due to the unique synergy of electrochemical reaction current and capacitance current during the discharge process, the HPSD exhibited a higher power density (26.2 kW kg−1) than the PEMFC (23.9 kW kg−1). The energy density (12.7 kWh kg−1) exhibited by HPSD was close to that of the PEMFC (13.5 kWh kg−1). Therefore, the concept of HPSD is to create a new method for developing next-generation electrochemical devices with high energy and power densities. • A hybrid PEMFC/supercapacitor device (HPSD) was proposed and fabricated. • The HPSD possesses high energy (12.7 kWh kg−1) and power densities (26.2 kW kg−1). • The reduced graphene oxide/Nafion/Pt electrode was used to fabricated the HPSD. • Reduced graphene oxide (rGO) was capacitive material, and Pt was electrocatalyst. • Nafion ionomers could connect the rGO sheets and the electrolyte (Nafion membrane). [ABSTRACT FROM AUTHOR]

Super alloys like Inconel 617 are extensively used in aerospace, gas turbines, chemical and food processing industry but it is extremely hard to machine from traditional methods and thereof non-traditional machining is usually engaged. Electric discharge machining (EDM) is good choice in this context as it is widely utilized in the industry for precision machining and making complex geometrical shapes in hard-to-cut materials. However, the intrinsic issues of low machining rate (MRR), dimensional overcuts and surface roughness (SR) limit its application. Therefore, the potentiality of the modified dielectric with nano powder and surfactant in aforementioned context was studied using three copper, brass and graphite as electrodes in EDM of Inconel 617. Taguchi L18 orthogonal array was used for experimentation considering nano powder type, powder concentration, surfactant type, surfactant concentration, dielectric type, electrode material and pulse time ratio as control variables. Results revealed that the addition of nano-alumina powder has proved to be the better choice in contrast to SiC for achieving high MRR. It has been noticed that average MRR found for alumina experiments was 33% more than that found with SiC. However, for SR and overcut the supremacy of SiC has been witnessed. Increase in powder concentration from 0.25 g/l to 0.625 g/l results in average increase of 15% in MRR. Whereas in case of SR, 7.5% increment is noticed as the powder concentration is raised from its 1st to 2nd level. In terms of surfactant, MRR provided by the S-80 based dielectric is 13% and 2.2% higher than that achieved with Tween-20 and Span-20 respectively. For the SR perspective, span 20 performs better than T-20 and S-80. Nevertheless, T-20 has found to the best choice for the attainment of better dimensional accuracy. The electrode of Cu provides highest MRR and minimum overcut whereas for SR, graphite electrode shows best results. The developed optimal settings confirm an improvement of 20.6%, 13.9% and 34% in the magnitudes of MRR, SR and overcut respectively during confirmation trials. Furthermore, multi-objective optimization has also been carried out for simultaneous optimization of responses. [ABSTRACT FROM AUTHOR]

The effect of co-sensitization and ZnS passivation on the photovoltaic performance of CdS quantum dot sensitized solar cells (QDSSCs) were investigated. The deposition of CdS, CdSe quantum dots (QD) and ZnS passivation on TiO 2 photoanode was carried out by successive ionic layer adsorption and reaction (SILAR) method. CdS/CdSe co-sensitization developed two staggered type-II heterojunctions at TiO 2 /CdS and CdS/CdSe interfaces and resulted a cascade energy band structure. This suitable band alignment facilitated the double charge transfer mechanism at each heterojunction and transported the electrons easily into the photoanode. The narrow bandgap sensitizers CdS and CdSe significantly improved the potential utilization of solar spectrum with more charge carrier generation. ZnS passivation on QD surface suppressed electrode/electrolyte interfacial charge recombination and facilitated more electron injection from QDs into TiO 2 photoanode. The EDAX elemental mapping results inferred that CdS, CdSe and ZnS have efficiently covered the TiO 2 surface. TiO 2 /CdS and CdS/CdSe interfaces and the amorphous nature of ZnS could be verified with HRTEM images. Hence, the co-sensitization and surface passivation played a significant role to enhance the PCE of CdS QDSSC from 1.9% to 4.05%. • Co-sensitization of CdS/CdSe quantum dots on TiO 2 photoanode resulted a cascade band alignment. • The staggered type-II heterojunctions have facilitated faster charge transport through double charge transfer mechanism. • Co-sensitization has widened the light absorption range with more charge carrier generation and increased current density. • ZnS passivation layer suppressed the recombination by passivating the defect sites on quantum dot surface. • Co-sensitization and surface passivation enhanced the PCE of CdS QDSSC from 1.9% to 4.05%. [ABSTRACT FROM AUTHOR]

Supercapacitors exhibit fast charging/discharging ability and have attracted considerable attention within the automotive, aerospace, and telecommunication industries. Porous carbons, prized for their high electrical conductivity and high surface area, have been attractive candidates for supercapacitor electrodes. Moving to thick electrodes is one strategy to further increase energy density due to a higher volume fraction of active material. However, thick electrodes suffer from sluggish charged species transport, which is why thin electrodes are currently favored. In this work, we investigate the use of computational optimization and additive manufacturing to design and fabricate thick porous electrodes with improved performance. Electrode performance was maximized by designing their morphologies via topology optimization and printing by projection micro stereolithography (PμSL) using commercial resin (PR48). The PR48 resin was then pyrolyzed (PR48-P) to create the final conductive electrode. The optimized PR48-P electrodes exhibited 99% improvement in capacitance compared to control electrodes printed with cubic lattice morphologies. To further improve performance, we formulated a resin combining graphene oxide (GO) and trimethylolpropane triacrylate (TMPTA). Electrodes printed with 3 wt% GO in TMPTA exhibited improved capacitance retention after pyrolysis compared to the PR48-P electrodes. This work demonstrates the benefits of using topology optimization to design electrodes and material development to improve functional properties of 3D printable electrodes. [Display omitted] • 3D printing of complex shaped electrodes by projection micro stereolithography. • Topology optimization is used to design porous electrodes with optimal energy density. • Adding graphene oxide into photocurable resin improves the capacitance retention of supercapacitors. [ABSTRACT FROM AUTHOR]

In this work, a series of Ruddlesden popper oxide materials S m 1 − x L a x S r 1 − x C a x N i O 4 − δ (x = 0.00, 0.05, 0.10, 0.15, and 0.20) were synthesized and their electrochemical behavior was investigated in 1 M KOH alkaline solution. Phase formation in all the samples is confirmed through XRD. SEM depicts the porous morphology of all the samples. FTIR confirms the presence of –OOH and –OH groups in several compositions. The Cyclic voltammetry curve of S m 0.90 L a 0.10 S r 0.90 C a 0.10 N i O 4 − δ and S m 0.80 L a 0.20 S r 0.80 C a 0.20 N i O 4 − δ indicates the presence of the combination of both pseudo-capacitance and electrochemical double-layer capacitance in these two electrodes. However, only the sample S m 0.90 L a 0.10 t S r 0.90 C a 0.10 N i O 4 − δ sample satisfies the condition of the general power law for pseudo capacitance. This material also shows the highest value of specific capacitance (910.20 F/g) and electrochemical double-layer capacitance (238.25 mF/cm2) among all the samples. XPS analysis reveals that oxidation states of the Nickel and Oxygen play a crucial role for the better electrochemical performance of the electrode. • A-site co-doping is used to tailor the properties of Ruddlesden–Popper SmSrNiO4-δ to improve the electrocatalytic activity. • Optimized Sm 0.90 La 0.10 Sr 0.90 Ca 0.10 NiO 4-δ exhibit superior specific capacitance and double layer capacitance. • Oxidation states of Nickle and oxygen have an important role in enhancing the electrochemical performance. • Sm 0.90 La 0.10 Sr 0.90 Ca 0.10 NiO 4-δ exhibit satisfied electrochemical performance as a hybrid capacitor. [ABSTRACT FROM AUTHOR]

[Display omitted] • The separation of oxygen and electron pathways is an underlying cause for the cell inconsistency. • Mixing electrode pathway at under-rib region is more important than at under-channel region. • The cell inconsistency can be reduced by up to 40% with little (3.3%) sacrificed performance. • The digitalization platform can provide fully observable physical and chemical information. Proton exchange membrane (PEM) fuel cell has been regarded as a promising approach to the decarbonization and diversification of energy sources. In recent years, durability and cost issues of PEM fuel cells are increasingly significant with the rapid increase of power density. However, the failure to maintain the cell consistency, as one major cause of the above issue, has attracted little attention. Therefore, this study intends to figure out the underlying cause of cell inconsistency and provide solutions to it from the perspective of multi-physics transport coupled with electrochemical reactions. The PEM fuel cells with electrodes under two compression modes are firstly discussed to fully explain the relationship of cell performance and consistency to electrode structure and multi-physics transport. The result indicates that one main cause of cell inconsistency is the intrinsic conflict between the separated transport and cooperated consumption of oxygen and electron throughout the active area. Then, a mixed-pathway electrode design is proposed to reduce the cell inconsistency by enhancing the mixed transport of oxygen and electron in the electrode. It is found that the mixing of pathways in electrodes at under-rib region is more effective than that at the under-channel region, and can achieve an up to 40% reduction of the cell inconsistency with little (3.3%) sacrificed performance. In addition, all the investigations are implemented based on a self-developed digitalization platform that reconstructs the complex physical–chemical system of PEM fuel cells. The fully observable physical information of the digitalized cells provides strong support to the related analysis. [ABSTRACT FROM AUTHOR]

It is tedious to machine high strength materials such as titanium alloy for making engineering products related to aerospace and medical applications due to its high corrosion resistance and low density. In this study, an endeavor was made to analyze the influence of tool electrodes in electrical discharge machining process for enhancing the machinability of Titanium α- β alloy. Copper, brass and tungsten carbide electrodes were utilized with iso energy pulse generator. It was observed that the use of copper electrode could enhance material removal mechanism due to its higher electrical conductivity. The better surface topography with tiny craters could be observed on machined specimen with tungsten carbide electrode owing to its high melting point. The IEPG generator can produce tiny craters with lower pulse energy and uniform energy distribution. Since it produces tiny crater and has higher melting point, the tungsten carbide tool electrode can create lower surface roughness than other electrodes. Brass electrode can create larger craters on the machined surface of titanium alloy specimens due to its low melting point. Hence it could create higher surface roughness and electrode wear. [ABSTRACT FROM AUTHOR]

The zinc electrowinning process demands considerable energy, prompting the quest for energy-efficient solutions to curtail costs. Hence, the development of energy-saving anode materials for zinc hydrometallurgy is an important issue. Herein, multilayered PbO 2 film materials were prepared through thermal decomposition and composite electrodeposition, yielding a new PbO 2 –ZrO 2 electrode featuring ZrO 2 particles as the second phase for energy-saving zinc electrowinning. The introduction of ZrO 2 leads to reduced PbO 2 crystal size, heightened the specific surface area of the electrode, and preferential growth of crystal planes. Electrochemical tests underscore that the PbO 2 –ZrO 2 electrode manifests a reduced charge-transfer resistance (R ct) and overpotential alongside a 46.15 % extension in service life compared to the pure PbO 2 electrode. Simulated zinc electrowinning experiment affirms PbO 2 –ZrO 2 electrode has a 3.63 % surge in the current efficiency and a substantial 244.61 kWh/t reduction in energy consumption relative to the traditional Pb–0.6wt%Ag anode. This study provides a strategic framework for designing and developing cost-efficient, cost-effective anode materials, promoting advancements in energy conservation and consumption reduction within zinc electrowinning processes. • A novel gradient film PbO 2 –ZrO 2 electrode was developed for zinc electrowinning. • The PbO 2 –ZrO 2 (10 g/L) electrode service life is improved by ∼46.15 %. • The current efficiency is higher (90.52%), and energy consumption is lower (2956.71 kW/t). • The introduction of ZrO 2 particles increases the specific surface area of the electrode. [ABSTRACT FROM AUTHOR]

MXenes are emerging as the next-generation materials for energy storage due to their substantial surface area, exceptional conductivity, and abundant surface-terminating groups. However, the tortuous path for ion transfer within the restacked layers significantly limits the electrochemical performance of multilayered MXenes. To overcome this, interlayer spacers have been introduced. These spacers help mitigate ion diffusion barriers and enhance the accessibility of active sites, thereby improving the overall efficiency and longevity of MXene-based supercapacitors and related devices. In this study, a rational material is designed by incorporating CoFe 2 O 4 and g-C 3 N 4 into the layers of MXene through ultrasonication for supercapacitor application. The physicochemical properties of the synthesized materials have been comprehensively characterized using diverse techniques, revealing that MXene/CoFe 2 O 4 /g-C 3 N 4 has successfully evolved into a multilayered structure possessing enhanced surface area, low restacking tendency, high pore diameter, and excellent pore volume. Leveraging these properties, it performs as a viable material for fabricating the working electrode with a specific capacitance (C sp) of 1506.2 F g−1 at a current density of 5 A g−1 in 3 M KOH. It shows good stability with 89 % capacitance retention over 7000 cycles. An asymmetric supercapacitor (ASC) constructed with MXene/CoFe 2 O 4 /g-C 3 N 4 as positive electrode and activated carbon as negative electrode exhibits an energy density of 79.8 Wh Kg−1 and power density of 1343.3 W Kg−1. Furthermore, it shows a capacitive retention of 91 % over 10,000 cycles. This MXene based composite, with excellent capacitance and outstanding stability, offers an appreciable performance in the field of sustainable energy storage. [Display omitted] • A promising electrocatalyst, MXene/CoFe 2 O 4 /g-C 3 N 4 is prepared by ultrasonication method. • It acts as a potential electrode material with specific capacitance of 1506.2 F g−1 at current density 5 A g−1. • Capacitive retention of 89 % up to 7000 cycles. • MXene/CoFe 2 O 4 /g-C 3 N 4 exhibits an energy density of 79.8 Wh Kg−1 and power density of 1343.3 W Kg−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • SHJ solar cells have proven itself by high PCE and field performance. • There is increasing emphasis on reducing the Ag consumption. • This paper describes high efficiency with minimum usage of Ag consumption. • We achieved the finger width about 22 μm and 26.5 μm and increased PCE upto 22.46 %. The Silicon heterojunction (SHJ) solar cell belongs to the most viable cell structure that enables low cost as well as high efficiency. For SHJ cells, silver (Ag) paste has been used through screen-printed process that is hardenable at low temperature. The procedure of screen printing is essential for improving the electrical properties because it allows electrodes to make good contact with the top layer of solar cells. This paper describes the experimental procedure to optimize the process condition for achieving comparatively high efficiency with minimum usage of Ag consumption. It was noticed that adequate contact among electrodes and uppermost transparent conductive oxide layer in SHJ solar cell depending considerably on squeeze speed, squeegee pressure, scraper speed, curing time and temperature. By controlling the snap-off distance of 1.4 mm, squeegee pressure at 0.3 MPa, scraper speed of 10 mm/sec, squeegee speed of 170 mm/sec, curing time of 20 min and curing temperature of 190 °C respectively, we achieved comparatively high efficiency of 22.46 %. [ABSTRACT FROM AUTHOR]

• A hierarchical MnCo 2 O 4 @MnWO 4 core-shell nanoarrays on NF is obtained. • 2. Nanoarrays and synergy provide high capacitance retention and rate performance. • 3. Unique structure and large specific surface area avail the diffusion of electron/ion. • 4. The ASC device shows an energy density of 36.46 Wh kg−1 at 750 W kg−1. Supercapacitors (SCs) are generally perceived as competitive possibilities for portable electronic products due to their exceptionally high power density and extended operational lifespan. Nevertheless, the relatively low energy density remains a crucial obstacle to its widespread application. A hierarchical MnCo 2 O 4 @MnWO 4 core-shell nanoarrays on nickel foam (NF) was designed and synthesized by utilizing the MnCo 2 O 4 nanosheet array as the backbone and the MnWO 4 nanosheet array as the shell via hydrothermal procedure and calcination. The MnCo 2 O 4 @MnWO 4 /NF electrode achieves 1428.5 F g−1 at 1 A g−1 with 97.8 % of its pristine capacity after 4000 cycles. The superior energy storage characteristic is a result of several factors, including the binder-free integrated electrode design, the synergistic effect between MnCo 2 O 4 and MnWO 4 , and abundant active sites. The assembled asymmetric supercapacitor (ASC) has an energy density of 36.46 Wh kg−1 at 750 W kg−1, and 85.4 % capacity reserved after 5000 cycles. [Display omitted] [ABSTRACT FROM AUTHOR]

Rationally synthesizing promising electrode material with nano-morphologies for excellent practical hybrid capacitor application lingers as a challenge. To complete the assignment, we design MnCo 2 O 4 @Ni 2.5 Mo 6 S 4.7 electrode via facial hydrothermal approach assisted with calcination and vulcanization processes in which the nano-structured material anchors on the nickel substrate. An ultrahigh specific capacitance of 3164 F g−1 at 1 A g−1 is delivered by the cathode electrode material. The specific capacitance of MnCo 2 O 4 @Ni 2.5 Mo 6 S 6.7 remains 97.2 % even after 8000 cycles. The as-fabricated hybrid capacitor (HC) produces 75.2 Wh kg−1 energy density at 2700 W kg−1 power density. The device shows high stability rate (87.5 % at 8 A g−1 of its original capacitance throughout 8000 cycles. The outcome of MnCo 2 O 4 @Ni 2.5 Mo 6 S 6.7 structure design demonstrates its potential utilizations in future smart micro/nano energy storage device. [Display omitted] [ABSTRACT FROM AUTHOR]

This study systematically explored the role of Mn(II) in the removal of 4-chlorophenol (4-CP) by electro-oxidation (EO) employing anodes with low oxygen evolution potential (OEP), i.e., Ti/RuO 2 -IrO 2 , Ti/Pt, and Ti/Ti 4 O 7 , as well as anodes with high OEP, namely, Ti/PbO 2 , Ti/SnO 2 , and boron-doped diamond (Si/BDD). Mn(II) significantly promoted 4-CP removal on the anodes with low OEP at fairly low current density (0.04 to 1 mA/cm2), but had minimal to negative impact on those with high OEP. Cyclic voltammetry and X-ray photoelectron spectra revealed that Mn(II) was oxidized to Mn(III), then to Mn(IV) on the anodes with low OEP, whereas its was oxidized directly to Mn(IV) on those with high OEP. Deposition of manganese oxide on the anodes with low OEP suppressed oxygen evolution reaction (OER) in EO process, but enhanced OER on those with high OEP. Quenching and spectral results consistently indicated that Mn(III) and Mn(IV) were the primary species responsible for enhancing 4-CP removal on the anodes with low OEP. These findings provide mechanistic insights into the redox transformation of Mn(II) in EO and the theoretical basis for a novel strategy to boost pollutant degradation in EO systems using low OEP anodes through coupling with the redox chemistry of manganese. [Display omitted] • Removal of 4-CP was significantly enhanced by Mn(II) in EO using anodes with low OEP. • Mn(II) had little to negative impact on 4-CP removal in EO using anodes with high OEP. • Mn(II) was oxidized to Mn(III)/Mn(IV) and suppressed OER on the anodes with low OEP. • Mn(II) was directly oxidized to Mn(IV) and enhanced OER on the anodes with high OEP. • Coupling Mn(II) with EO using low OEP anodes could greatly enhance pollutant removal. [ABSTRACT FROM AUTHOR]

The present work includes fabrication of a binary and ternary and composites of reduced graphene oxide (RGO), Polyaniline (Pani), and cobalt Prussian blue analog (Co-PA) for high performance supercapacitor. The materials were characterized using XRD, SEM, FT-IR, and BET techniques. The results confirm the formation of the desired nanocomposites. The electrochemical properties were evaluated in three electrode configuration using CV, CCD and EIS methods. The ternary composite of RGO@Pani@Co-PA showed better electrochemical properties than that obtained from the binary composites as well as their constituent components. The ternary-based sample had a specific capacitance of 490 Fg-1 at a current density of 1 A g-1 and a minimal capacitance loss of 93.9% after 3000 electric cycles. The ternary composites' remarkable electrochemical performance has been attributed to their well-thought-out, distinctive architecture, which offers a substantial surface area and promotes synergistic effects among the other ingredients. The ternary RGO@Pani@Co-PA composite was used as the anode electrode (positive) and activated carbon as the cathode (negative) materials in the assembly of the asymmetric supercapacitor (ASC) device. Over a wide potential window of 2 V, the fabricated ASC had a remarkable specific energy of 58.9 Wh kg-1 at a specific power of 9210 W kg-1 and 88.5% device capacitance stability after 5000 cycles of charge/discharge. [ABSTRACT FROM AUTHOR]

Nanomaterials are a potential alternative to conventional random resistive access memory (ReRAM) in non-volatile memory (NVM) due to their unique electrical and physical properties. Nevertheless, obtaining a specific NVM characteristic [particularly Write-Once-Read-Many (WORM)] using carbon-based electrodes necessitates further assessment. This study proposed a reinvented methodology for TiO 2 -based devices to produce WORM memory behavior using the doctor blade method. A carbon/graphite counter electrode (Gr/Cb) was fabricated and characterized for TiO 2 -based resistive switching devices. Consequently, the Gr/Cb electrode device quickly transitioned from a high to low resistance state, suggesting WORM memory behavior. Approximately 66.7 % improvement (∼1.8 V–∼0.6 V) was observed in the required applied voltage when the active area was reduced, indicating lower power consumption. Overall, this study provided evidence of the approach's feasibility in practical applications, demonstrating lower costs and simplicity. The structure also highlighted the importance of understanding the WORM behavior for effectively utilizing carbon-based electrodes in non-volatile memories. [Display omitted] • Novel carbon-based electrodes were integrated into TiO 2 -based ReRAM devices. • The lowest ON voltage were ∼0.6 V and ∼1.8 V for ITO/TiO 2 /Gr/Cb (pixel) and ITO/TiO 2 /Gr/Cb (strip) memory devices. • WORM behavior was achieved using a TiO 2 -based ReRAM device. • VCM theory could be used to explain the ohmic behaviour and Schottky emission mechanism. [ABSTRACT FROM AUTHOR]

MoS 2 -based electrodes are gaining attention in capacitive deionization for their high charge storage capacity and electrolyte ion diffusion. However, the development is hindered by strong aggregation, volume changes, and high charge transfer resistance. Herein, one-dimensional Polypyrrole (PPy) microtubes with MoS 2 1T/2H hybrid-phase nanosheets (PPy@MoS 2) was successfully synthesized via a self-templated method. Systematic characterization and electrochemical measurements proved that PPy@MoS 2 owned abundant active sites, smooth charge and ion transport. With precise structural and phase adjustments, PPy@MoS 2 achieved high desalination capacity (159.6 mg g−1) and rate (3.2 mg g−1 min−1). The core-shell structure and hybrid phase provided excellent charge efficiency, cycling stability, and low energy consumption (0.22 kWh kg−1). These features showed its potential for practical desalination applications. This work presents a significant advancement in high-performance MoS 2 -based electrodes for capacitive deionization. The core-shell structure and 1T/2H hybrid phase endowed PPy@MoS 2 high desalination capacity, desalination rate, excellent charge efficiency, cycling stability and low energy consumption, indicating its significant potential and benefits for practical applications in seawater desalination. [Display omitted] • PPy@MoS 2 exhibited both 1T and 2H phases. • An excellent desalination capacity of 159.6 mg g−1 was achieved. • PPy@MoS 2 showed low energy consumption of 0.22 kWh kg−1. [ABSTRACT FROM AUTHOR]