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The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem. Among various nitrate removal technologies, electrocatalytic nitrate reduction reaction (eNO3RR) has been widely studied for its advantages of being eco-friendly, easy to operate, and controllable under environmental conditions with renewable energy as the driving force. Transition metal-based catalysts (TMCs) have been widely used in electrocatalysis due to their abundant reserves, low costs, easy-to-regulate electronic structure and considerable electrochemical activity. In addition, TMCs have been extensively studied in terms of the kinetics of the nitrate reduction reaction, the moderate adsorption energy of nitrogen-containing species and the active hydrogen supply capacity. Based on this, this review firstly discusses the mechanism as well as analyzes the two main reduction products (N2 and NH3) of eNO3RR, and reveals the basic guidelines for the design of efficient nitrate catalysts from the perspective of the reaction mechanism. Secondly, this review mainly focuses on the recent advances in the direction of eNO3RR with four types of TMCs, Fe, Co, Ni and Cu, and unveils the interfacial modulation strategies of Fe, Co, Ni and Cu catalysts for the activity, reaction pathway and stability. Finally, reasonable suggestions and opportunities are proposed for the challenges and future development of eNO3RR. This review provides far-reaching implications for exploring cost-effective TMCs to replace high-cost noble metal catalysts (NMCs) for eNO3RR. [ABSTRACT FROM AUTHOR]

Take after the advantages of lithium-ion battery (LIB) and redox flow battery (RFB), semi-solid flow battery (SSFB) is a promising electrochemical energy storage device in renewable energy utilization. The flowable slurry electrode realizes decouple of energy and power density, while it also brings about new challenge to SSFBs, electron transport between active material and the out circuit. In this consideration, three types of current collectors (CCs) are applied to study the resistance and electrochemical performances of slurry cathodes within pouch cells for the first time. It proves that the electronic resistance (Re) between slurry electrode and the CC plays a decisive role in SSFB operation, and it is so large when Al foil is adopted that the cell cannot even work. Contact angle between Ketjen black (KB) slurry without active material (AM) and the CC is a preliminarily sign for the Re, the smaller the angle, the lower the resistance, and the better electrochemical performance of the cell. [ABSTRACT FROM AUTHOR]

A significant amount of energy can be produced using renewable energy sources; however, storing massive amounts of energy poses a substantial obstacle to energy production. Economic crisis has led to rapid developments in electrochemical (EC) energy storage devices (EESDs), especially rechargeable batteries, fuel cells, and supercapacitors (SCs), which are effective for energy storage systems. Researchers have lately suggested that among the various EESDs, the SC is an effective alternate for energy storage due to the presence of the following characteristics: SCs offer high-power density (PD), improvable energy density (ED), fast charging/discharging, and good cyclic stability. This review highlighted and analyzed the concepts of supercapacitors and types of supercapacitors on the basis of electrode materials, highlighted the several feasible synthesis processes for preparation of metal oxide (MO) nanoparticles, and discussed the morphological effects of MOs on the electrochemical performance of the devices. In this review, we primarily focus on pseudo-capacitors for SCs, which mainly contain MOs and their composite materials, and also highlight their future possibilities as a useful application of MO-based materials in supercapacitors. The novelty of MO's electrode materials is primarily due to the presence of synergistic effects in the hybrid materials, rich redox activity, excellent conductivity, and chemical stability, making them excellent for SC applications. [ABSTRACT FROM AUTHOR]

The complex multistep electrochemical reactions of lithium polysulfides and the solid--liquid--solid phase transformation involved in the S8 to Li2S reactions lead to slow redox kinetics in lithium--sulfur batteries (Li--S batteries). However, some targeted researches have proposed strategies requiring the introduction of significant additional inactive components, which can seriously affect the energy density. Whereas polymer binders, proven to be effective in suppressing shuttle effects and constraining electrode volume expansion, also have promising potential in enhancing Li--S batteries redox kinetics. Herein, a novel aqueous polymer binder is prepared by convenient amidation reaction of fully biomaterials, utilizing its inherent rich amide groups for chemisorption and redox mediating ability of thiol groups to achieve adsorption redox-mediated synergism for efficient conversion of polysulfides. Li--S batteries based on N-Acetyl-L-Cysteine-Chitosan (NACCTS) binder exhibit high initial discharge specific capacity (1260.1 mAh g-1 at 0.2 C) and excellent cycling performance over 400 cycles (capacity decay rate of 0.018% per cycle). In addition, the batteries exhibit great areal capacity and stable capacity retention of 83.6% over 80 cycles even under high sulfur loading of 8.4 mg cm-2. This work offers a novel perspective on the redox-mediated functional design and provides an environmentally friendly biomaterials-based aqueous binder for practical Li--S battery. [ABSTRACT FROM AUTHOR]

Transition Metal Oxides (TMOs) have drawn significant attention due to their diverse range of properties and applications. The partially filled d orbitals of the transition metal ions, with highly electronegative oxygen atoms, give rise to unique electronic structures that lead to multiple applications due to their magnetic, optical, and structural properties. These properties have a direct influence on chemical reactions that enable tailoring materials for specific applications in catalysis, such as electrocatalysis and photocatalysis. While the potential of TMOs is promising, their development for enhanced functional properties poses numerous challenges. Among these challenges, identifying the appropriate synthesis processes and employing optimal characterization techniques are crucial. In this comprehensive review, an overview of recent trends and challenges in the synthesis and characterization of highly functional TMOs as well as ceramics will be covered with emphasis on catalytic applications. Mesoporous materials play a key role in augmenting their functionality for various applications and will be covered. Ab-initio modeling aspects for the design and development of novel TMO will be also discussed. [ABSTRACT FROM AUTHOR]

Each year, the rising demand for palm oil generates large amounts of palm kernel shell waste. Discarded palm kernel shells can produce activated carbon, crushed shells, liquified fumes, and other derivatives; however, their indiscriminate disposal persists, raising issues related to the environment and economy. Therefore, the purpose of this study is to investigate the use of palm kernel shell as a corrosion inhibitor for thermo-mechanically treated steel in a seawater environment using gravimetric and electrochemical techniques, as well as surface tests at varying concentrations. The findings demonstrated that the palm kernel shell inhibited the cathodic and anodic processes by adsorption on the steel surface, which followed the Langmuir adsorption isotherm. The inhibitor exhibited a 98% inhibitory efficiency at 500 ppm concentration. Scanning electron microscopy analysis verified the thin films of the inhibitor on steel surface in seawater solution. Fourier transform infrared spectroscopy results show that the extract's components prevent the steel corrosion through an adsorptive mechanism. According to the inhibitor economic evaluation, employing the palm kernel shell extract is less expensive than utilizing conventional inhibitors. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive review on the electrochemical synthesis and functional properties of metal and alloy-based composition coatings. Nowadays, electrochemical synthesis is considered a versatile and widely used technique for producing metal and alloy coatings with precisely controlled composition, thickness, and microstructure. These coatings offer a variety of functional properties that can enhance the performance and durability of various substrates. It typically involves immersing a substrate (cathode) in an electrolytic solution containing dissolved metal ions. A current is applied between the cathode and an anode, causing the metal ions to be reduced and deposited onto the cathode surface as a coating. The specific properties of the coating, such as composition, thickness, and morphology, can be controlled by various parameters, including electrolyte composition, current density and potential, temperature and pH as well as substrate material and pretreatment. The utilization of electrochemical methods in coating fabrication has gained significant attention due to their efficiency, precision, and environmental friendliness. As such, the focus of this review is on the synthesis processes, structural characterization, and functional properties of coatings comprising various metals and alloys to help understand electrochemical deposition techniques for tailored coatings with enhanced properties for diverse applications by summarizing previous studies. [ABSTRACT FROM AUTHOR]

Stretchable power sources, especially stretchable lithium-ion batteries (LIBs), have attracted increasing attention due to their enormous prospects for powering flexible/wearable electronics. Despite recent advances, it is still challenging to develop ultra-stretchable LIBs that can withstand large deformation. In particular, stretchable LIBs require an elastic electrolyte as a basic component, while the conductivity of most elastic electrolytes drops sharply during deformation, especially during large deformations. This is why highly stretchable LIBs have not yet been realized until now. As a proof of concept, a super-stretchable LIB with strain up to 1200% is created based on an intrinsically super-stretchable polymer electrolyte as the lithium-ion conductor. The superstretchable conductive system is constructed by an effective diblock copolymerization strategy via photocuring of vinyl functionalized 2-ureido-4-pyrimidone (VFUpy), an acrylic monomer containing succinonitrile and a lithium salt, achieving high ionic conductivity (3.5 × 10-4 mS cm-1 at room temperature (RT)) and large deformation (the strain can reach 4560%). The acrylic elastomer containing Li-ion conductive domains can strongly increase the compatibility between the neighboring elastic networks, resulting in high ionic conductivity under ultra-large deformation, while VFUpy increases elasticity modulus (over three times) and electrochemical stability (voltage window reaches 5.3 V) of the prepared polymer conductor. At a strain of up to 1200%, the resulting stretchable LIBs are still sufficient to power LEDs. This study sheds light on the design and development of high-performance intrinsically super-stretchable materials for the advancement of highly elastic energy storage devices for powering flexible/wearable electronics that can endure large deformation. [ABSTRACT FROM AUTHOR]

An Au electrode modified with Persian blue (PB), has been applied to the electrocatalytic oxidation of uric acid, which reduced the overpotential by about 165 mV with obviously increased current response. The cyclic voltammetry method was employed to characterize the electrochemical behavior of the chemically modified electrode. The electrocatalytic efficiency of the modified electrode towards uric acid oxidation process depends on the solution pH value, and the optimum pH value for the oxidation of uric acid is 7.0. The overall number of electrons involved in the catalytic oxidation of uric acid and the number of electrons involved in the ratedetermining steps are 2, respectively. And diffusion coefficient of the uric acid compound was estimated using the chronoamperometry technique. The proposed method is simple and rapid with excellent selectivity and sensitivity within the linear range of 0.2-2 mM uric acid with a detection limit of M and correlation coefficient R2 = 0.9913. [ABSTRACT FROM AUTHOR]

In order to find an effective decolorization method for dye wastewaters, the present work aims at studying the treatment efficiency of an azo dye Acid Red 14 (AR14) by Electro-Fenton process using an undivided electrochemical cell containing different electrode materials. The optimal removal efficiency was obtained using carbon felt or glassy carbon (cathode) and platinum (anode) electrodes. The method is based on the reaction of electrochemically produced hydroxyl radicals leading to oxidative degradation of the AR14. To find the best conditions for treatment of AR14 dye, the effects of Fe2+ concentration, current density, the effect of pH initial, and the nature of support electrolyte were studied. The results showed 94 % removal efficiency in 30 minutes with 120 mA/cm² of electrolysis current, 0.2 mM of Fe2+, and pH = 3. However, the decolorization efficiency measurements confirmed that the Electro-Fenton process with the platinum anode and the carbon felt cathode was more efficient. [ABSTRACT FROM AUTHOR]

The electric double layer (EDL) is the most important region for electrochemical and heterogeneous catalysis. Because of it, its modeling and investigation are something that can be found in the literature for a long time. However, nowadays, it is still a hot topic of investigation, mainly because of the improvement in simulation and experimental techniques. The present review aims to present the classical models for the EDL, as well as presenting how this region affects electrochemical data in everyday experimentation, how to obtain and interpret information about EDL, and, finally, how to obtain some molecular point of view insights on it. [ABSTRACT FROM AUTHOR]

Digital medicine based on the integration of all medical data from a particular patient has become a reality today, thanks to information technology. Traditional medical examinations can be supplemented by assessment results of the oxidative-anti-oxidative (OAO) status of the body. Electrochemical sensors are able to not only determine the integral indicators of the OAO system of the body but also to depict details of the processes occurring in the system. The main obstacle to the widespread use of electrochemical sensors in medical diagnostics is the extremely small amount of received information in comparison to the tens of thousands of known human diseases. The problem can be eliminated only by rethinking the purpose of electrochemical measurement within the framework of thermodynamics of information processes and information theory. In the information paradigm of electrochemical analysis of biological fluids, a sample is considered an electrochemical message created by a sensor. The purpose of electrochemical measurement is to obtain information in a volume sufficient to identify the sample composition within the range of possible concentrations of its components. The fundamentals of the thermodynamics of information processes are considered and conclusions that are of practical importance for the development of electrochemical sensors and analyzers are derived. It is shown that the potentiostatic control of the sensor is physically impacted by the electromechanical instability of the electrical double layer, which is the main source of sensor signal noise. Estimates of a minimum amount of analytical signal information required for the identification of a sample of known composition, such as a biological fluid, are provided. Examples of highly informative analytical signals for flowing and stationary samples are presented. Problems related to the visualization of such signals are noted. [ABSTRACT FROM AUTHOR]

The paper presents the electrochemical production of composite zinc matrix coatings using Al2O3 as dispersed phases. It was found that by correlating the working parameters with the concentration of the dispersed phase in the electrolyte, the mechanical characteristics and the corrosion resistance of the deposits could be improved. [ABSTRACT FROM AUTHOR]

n-conducting materials such as chiral polythiophenes exhibit excellent electrochemical stability in doped and undoped states on electrode surfaces (chiral electrodes), which help tune their physical and electronic properties for a wide range of uses. To overcome the limitations of traditional surface immobilization methods, an alternative pathway for the detection of organic and bioorganic targets using chiral electrodes has been developed. Moreover, chiral electrodes have the ability to carry functionalities, which helps the immobilization and recognition of bioorganic molecules. In this review, we describe the use of polythiophenes for the design of chiral electrodes and their applications as electrochemical biosensors. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells are relevant systems for power generation. However, they suffer from a lack of reliability, mainly due to their structural complexity. Indeed, their operation involves electrochemical, thermal, and electrical phenomena that imply a strong coupling, making it harder to maintain nominal operation. This complexity causes several issues for the design of appropriate control, diagnosis, or fault-tolerant control strategies. It is therefore mandatory to understand the fuel cell structure for a relevant design of these kinds of strategies. This paper proposes a fuel cell fault structural analysis approach that leads to the proposition of a structural graph. This graph will then be used to highlight the interactions between the control variables and the functionalities of a fuel cell, and therefore to emphasize how changing a parameter to mitigate a fault can influence the fuel cell state and eventually cause another fault. The final aim of this work is to allow an easier implementation of an efficient and fault-tolerant control strategy on the basis of the proposed graphical representation. [ABSTRACT FROM AUTHOR]

Renewable resources and their byproducts are becoming of growing interest for alternative energy. Here, we have demonstrated the use of Arkansas' most important crop, soy, as a carbon precursor for the synthesis of carbonized activated materials for supercapacitor applications. Different soy products (soymeal, defatted soymeal, soy flour and soy protein isolate) were converted into carbonized carbon and co-doped with phosphorus and nitrogen simultaneously, using a facile and time-effective microwave synthesis method. Ammonium polyphosphate was used as a doping agent which also absorbs microwave radiation. The surface morphology of the resulting carbonized materials was characterized in detail using scanning electron microscopy. X-ray photoelectron spectroscopy was also performed, which revealed the presence of a heteroelemental composition, along with different functional groups at the surface of the carbonized materials. Raman spectroscopy results depicted the presence of both a graphitic and defect carbon peak, with defect ratios of over one. The electrochemical performance of the materials was recorded using cyclic voltammetry in various electrolytes including acids, bases and salts. Among all the other materials, soymeal exhibited the highest specific capacitance value of 127 F/g in acidic electrolytes. These economic materials can be further tuned by changing the doping elements and their mole ratios to attain exceptional surface characteristics with improved specific capacitance values, in order to boost the economy of Arkansas, USA. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the possibility of plutonium quantification within the electrorefiner vessel of an electrochemical separation facility via the use of the (α,n) neutron signature from dissolved actinides. As a potential alternative means to traditional spontaneous fission tracking, such an analysis may provide a more reliable tracking capability of plutonium within systems that produce a mixed matrix sample that yields a large (α,n) source term relative to that of spontaneous fission. This assessment includes an evaluation and breakdown of nuclides within the refining unit to differentiate the source of neutrons and then the ratio between (α,n) emissions to total neutron emissions given a range of fuel parameters. Next, we provide an assessment of the origin of (α,n) neutrons in relation to multiple isotopes of plutonium to determine the potential of a direct tracking method. Preliminary results indicate that the (α,n) contribution for electrochemical systems is much higher than in its aqueous counterpart and rivals spontaneous fission yield in terms of magnitude. Furthermore, 238Pu is shown to be a main contributor to the (α,n) yield for the fuel examined in this study. [ABSTRACT FROM AUTHOR]

The Ragone plot (RP) compares devices in energy and power density characteristics, helping engineers decide on a specific energy storage system for technological applications. RP would contrast the performance of several technologies together under similar boundary conditions. Unfortunately, that is not what is happening for electrochemical double‐layer capacitors (EDLCs) because conditions for calculating energy and power are not standardized in the literature, resulting in severe discrepancies in the obtained values. With this widespread misconception, RP may become an unreliable tool for characterizing EDLCs. An intervention in this vital issue now becomes necessary. To put action on that, a rational strategy for dealing with measurements needed for EDLCs and calculations to prepare a reliable RP is reported here. This manuscript presents a step‐by‐step procedure to provide a correct RP. Also, simple theoretical demonstrations of how to get each fundamental equation are presented. In general, this work contributes as a guide to obtain reliable RPs for EDLCs. [ABSTRACT FROM AUTHOR]

Due to severe energy crisis and environmental problems, green and renewable electrochemical energy devices such as fuel cells and metal–air batteries have attracted great attention, where oxygen reduction reaction (ORR) plays a vital role. The rational design of efficient and robust single‐atom catalysts (SACs) is vital but challenging toward ORR. Here, recent developments of single‐atom ORR catalysts in fuel cells and Zn–air batteries are systematically summarized, focusing on transition‐metal‐based electrocatalysts including single or dual Fe, Co, Ni, Cu, Zn, Pd, Ag, and Pt sites. At the atomic level, different synthesis methods and characterization techniques are introduced. Theoretical studies of ORR mechanisms are documented. The active sites and structure–property relationships of SACs for ORR are highlighted, and the performances of proton exchange membrane fuel cells (PEMFCs), anion exchange membrane fuel cells (AEMFCs), and Zn–air batteries are discussed. The great challenges and future directions of SACs in fuel cells and Zn–air batteries are presented. [ABSTRACT FROM AUTHOR]

This document is a corrigendum for an article titled "Enhanced electrochemical properties of catalyst by phosphorous addition for direct urea fuel cell." The correction addresses an error in the funding statement, where Gachon University was omitted. The authors apologize for the mistake and clarify that it does not affect the scientific conclusions of the article. The original article has been updated. The document also includes a note from the publisher stating that the claims expressed in the article are solely those of the authors and do not necessarily represent the views of their affiliated organizations or the publisher. [Extracted from the article]

Corrosion reactions are often complex heterogeneous reactions that are accelerated by interactions such as: common kinetic considerations, electrolyte chemical composition, mass transfer between the electrolyte and the metal surface, Different surface effects such as adsorption, desorption and surface hardness are determined. The interactions between these factors make it difficult to reproduce electrochemical data or precise conditions that cause a metal to be corroded. These are the experimental factors that must be considered when corrosion tests are being designed. Ignoring these factors can produce data that does not provide the true corrosion behavior of the test metal under study. This paper presents the relationship between the inherent errors of corrosion measurement and suggestions on how to handle variability of electrochemical data. [ABSTRACT FROM AUTHOR]

Inhibition effect of the synergistic combination of thymus mastichina and illicium verum oil extracts (TMAV) on the corrosion inhibition of low carbon steel in 0.5 M H2SO4 and HCl solution was studied by weight loss analysis, potentiodynamic polarization, open circuit potential measurement, ATF-FTIR spectroscopy, and optical microscopy and macroscopic characterization. Results from weight loss shows TMAV performed more effectively in H2SO4 solution compared to HCl with optimal inhibition efficiency of 81.24% and 68.33%. Effective inhibition performance was observed at all TMAV concentration in H2SO4 compared to HCl where TMAV performed poorly until 5% concentration. The optimal inhibition performances from potentiodynamic polarization are 80.85% and 70.43%. The corresponding corrosion current density and polarization resistance are 7.16 × 105 A/cm2 and 8.01 × 105 A/cm2, and 331.73 and 284 Ω. TMAV exhibited mixed type inhibition effect in both acid solutions, strongly influencing the anodic-cathodic plot configurations with respect to concentration. Open circuit potential plots without TMAV were significantly electronegative compared to the plots at 1% and 5% TMAV concentration which were relative electropositive due to decreased thermodynamic tendency of the carbon steel to corrode. The corresponding plots at 1% and 5% TMAV concentration from HCl solution were thermodynamically unstable with significant active-passive corrosion behaviour. TMAV inhibited through chemisorption adsorption according to Langmuir and Freudlich adsorption isotherms in H2SO4 solution, and Frumkin and Freundlich adsorption isotherms in HCl solution with correlation coefficient values between 0.7 and 0.9. FTIR spectroscopic analysis exposed the functional groups and atomic bonds responsible for corrosion inhibition. [ABSTRACT FROM AUTHOR]

This study developstheoretical bases for the electrochemical process of cleaning soils from oil, oil products and highly mineralized reservoir water. The article experimentally and theoretically reveals patterns of reducing the content of polluting oil products in soils of various types during the small voltage passing. The optimal amount of electricity for the effective removal of various types of pollution was required. For the implementation of a electrochemical soil cleaning process a scheme of an original installation with placement of electrodes in the soil was studied. It reduces the resistance between the electrodes. The technical and economical calculations to determine energy costs of the electrochemical installation for cleaning oil-contaminated soils included: the number of electrodes; the voltage depending on the properties of the soil; the area; the depth of contamination of the soil to be treated;azndthe parameters of the electrodes. This allowed us to determine and develop the required degree of cleaning. [ABSTRACT FROM AUTHOR]

One of the most important and urgent problems facing the metallurgical industry is the problem of processing dump mattes (DM). These are alloys of sulfides of various metals, and in some locations have accumulated to such an extent that they fill entire landfills with environmentally hazardous substances. During prolonged storage in air, DM decomposes and produces toxic substances. Therefore it is important to find an environmentally safe way to store or processes DM. The available information on the technologies for processing sulfide-oxide metallurgical raw materials and sources of DM formation are analysed in this study. Chemical analysis of the DM indicates a high iron content, which a priori determines the high conductivity of dump materials. The aim of this research is to examibne the physicochemical properties of the DM melts of the Kadamjai antimony industrial complex, in which, according to the technological schedule, iron and antimony are accumulated in sulfide form, followed by pyroelectrochemical processing of them into commodity products in the case of optimal metal current yields and good extraction. The electrical conductivity (æ) of the industrial DM melt is characteristic of multifunctional conductors with a predominant semiconductor mechanism of conductivity. The addition of a heteropolar additive (Na2S) into the DM melt suppresses the electronic component of conductivity and decreaseds æ in the system to values that are typical for ionic melts. Current-voltage characteristics for the composition of the system with 60 and 70 mol. % Na2S indicate polarization in the melts. The electrolysis of DM-Na2S melts is accompanied by the release of sulfur on the anode. For a final assessment of the possibility of using electrochemical processing of DM melts into antimony metal, it is recommended that a preliminary economic calculation of the entire technological process be performed. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries have captured widespread attention for grid-scale energy storage owing to the natural abundance of sodium. The performance of such batteries is limited by available electrode materials, especially for sodium-ion layered oxides, motivating the exploration of high compositional diversity. How the composition determines the structural chemistry is decisive for the electrochemical performance but very challenging to predict, especially for complex compositions. We introduce the “cationic potential” that captures the key interactions of layered materials and makes it possible to predict the stacking structures. This is demonstrated through the rational design and preparation of layered electrode materials with improved performance. As the stacking structure determines the functional properties, this methodology offers a solution toward the design of alkali metal layered oxides. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) have emerged as a class of structural alloys with various attractive properties, and their application in additive manufacturing, which enables unprecedented thermal history and geometrical complexity, is promising for realising advanced materials. This study investigates the corrosion behaviour and passive film characteristics of an equimolar AlCoCrFeNi HEA additively manufactured by electron beam melting (EBM). Potentiodynamic polarisation in a 3.5 wt% NaCl solution revealed that the bottom part of the EBM specimen shows better corrosion performance than a conventionally prepared cast specimen in terms of both corrosion and passivation current density, while a continuous increase in the current density without any apparent passivity was observed during the anodic polarisation of the top part. The electrochemical impedance spectroscopic study indicated significant differences in the passive film characteristics between the specimens, and revealed an enhanced charge-transfer resistance and the formation of a more protective passive film of the bottom part. The elemental redistribution, in particular, the enrichment of Cr in the B2 phase during the post-melt high-temperature exposure of the alloy during EBM, was responsible for the improved stability of the passive film, retarding the selective dissolution of the B2 phase in the bottom part. These findings indicate that the microstructural evolution caused by 'in situ annealing' during the EBM process significantly influences the corrosion behaviour of the HEA. [ABSTRACT FROM AUTHOR]

The study and determination of the antioxidant capacity of the Greigia Sphacelata fruit were carried out. G. sphacelata is an endemic fruit of central-southern Chile, better known as Chupón or Quiscal. Spectrophotometric and modified ORAC test were developed for antioxidant capacity determinations, and later an electrochemical method was developed by differential impulse voltammetry (DPV) with a vitreous carbon electrode for the quantification of the antioxidant capacity expressed in equivalent of the Trolox standard in µmolL-1. Once the voltammetric test was developed, the correlation study between both methods used to determine the antioxidant capacity of Greigia sphacelata was carried out. The results of the determination of the antioxidant capacity of Greigia sphacelata by ORAC test report an antioxidant capacity of 3525 µmol/100g equivalents of Trolox. Concerning the concentration obtained by the electrochemical methodology, 724 µmol/100g Trolox equivalents is obtained for a linear correlation r = 0.969 with the spectrophotometric method. [ABSTRACT FROM AUTHOR]

Nitrogenase is the only enzyme capable of reducing N2 to NH3. This challenging reaction requires the coordinated transfer of multiple electrons from the reductase, Fe-protein, to the catalytic component, MoFe-protein, in an ATP-dependent fashion. In the last two decades, there have been significant advances in our understanding of how nitrogenase orchestrates electron transfer (ET) from the Fe-protein to the catalytic site of MoFe-protein and how energy from ATP hydrolysis transduces the ET processes. In this review, we summarize these advances, with focus on the structural and thermodynamic redox properties of nitrogenase component proteins and their complexes, as well as on new insights regarding the mechanism of ET reactions during catalysis and how they are coupled to ATP hydrolysis. We also discuss recently developed chemical, photochemical, and electrochemical methods for uncoupling substrate reduction from ATP hydrolysis, which may provide new avenues for studying the catalytic mechanism of nitrogenase. [ABSTRACT FROM AUTHOR]

In this theoretical work, we present for the first time voltammetric results of a surface multistep electron transfer mechanism that is associated with a preceding chemical reaction that is linked to the first electron transfer step. The mathematical model of this socalled "surface CEE mechanism" is solved under conditions of square-wave voltammetry. We present relevant set of results portraying the influence of kinetics and thermodynamics of chemical step to the features of simulated voltammograms. In respect to the potential difference at which both electrode processes occur, we consider two different situations. In the first scenario, both peaks are separated for at least |150 mV|, while in the second case both peaks occur at same potential. Under conditions when both peaks are separated for at least |150 mV|, the first process can be described with the voltammetric features of a surface CE mechanism, while the second peak gets attributes of a simple surface electrode reaction. When both peaks take place at same potential, we elaborate an elegant methodology to achieve separation of both overlapped peaks. This can be done by modifying the concentration of the substrate "Y" in electrochemical cell that is involved in the preceding chemical reaction. The results of this work can be of big assistance to experimentalists working in the field of voltammetry of metal complexes and drug-drug interactions. [ABSTRACT FROM AUTHOR]

Bimetallic catalysts can improve CO2 reduction efficiency via the combined properties of two metals. CuPd shows enhanced CO2 reduction activity compared to copper alone. Using differential electrochemical mass spectrometry (DEMS) and electrochemical infrared (IR) spectroscopy, volatile products and adsorbed intermediates were measured during CO2 and CO reduction on Cu and CuPd. The IR band corresponding to adsorbed CO appears 300 mV more positive on CuPd than that on Cu, indicating acceleration of CO2 reduction to CO. Electrochemical IR spectroscopy measurements in CO-saturated solutions reveal similar potentials for CO adsorption and CO32− desorption on CuPd and Cu, indicating that CO adsorption is controlled by desorption of CO32−. DEMS measurements carried out during CO reduction at both electrodes showed that the onset potential for reduction of CO to CH4 and CH3OH on CuPd is about 200 mV more positive than that on Cu. We attribute these improvements to interaction of Cu and Pd, which shifts the d-band center of the Cu sites. [ABSTRACT FROM AUTHOR]

A new approach has been developed to improve sensing performances of electrochemically grown Au nanostructures (AuNSs) based on the pre-seeding of the electrode. The pre-seeding modification is simply carried out by vacuum thermal deposition of 5 nm thin film of Au on the substrate followed by thermal annealing at 500 °C. The electrochemical growth of AuNSs on the pre-seeded substrates leads to impressive electrochemical responses of the electrode owing to the seeding modification. The dependence of the morphology and the electrochemical properties of the AuNSs on various deposition potentials and times have been investigated. For the positive potentials, the pre-seeding leads to the growth of porous and hole-possess networks of AuNSs on the surface. For the negative potentials, AuNSs with carved stone ball shapes are produced. The superior electrode was achieved from AuNSs developed at 0.1 V for 900 s with pre-seeding modification. The sensing properties of the superior electrode toward glucose detection show a high sensitivity of 184.9 µA mM−1 cm−2, with a remarkable detection limit of 0.32 µM and a wide range of linearity. The excellent selectivity and reproducibility of the sensors propose the current approach as a large-scale production route for non-enzymatic glucose detection. [ABSTRACT FROM AUTHOR]

Recent experimental study shows that the pre-lithiated MoS2 monolayer exhibits an enhanced electrochemical performance, coulombic efficiency of which is 26% higher than the pristine MoS2 based anode. The underlying mechanism of such significant enhancement, however, has not yet been addressed. By means of density functional theory (DFT) calculations, we systematically investigated the adsorption and diffusion behavior of lithium (Li) atoms on the MS2 (M = Mo, W, V) monolayers. On the pre-lithiated MS2 monolayers, the adsorption energy of extra Li ions are not significantly changed, implying the feasibility of multilayer adsorption. Of importance, the Li diffusion barriers on pre-lithiated MS2 are negligibly small because of the charge accumulation between the diffusing Li ions and the pre-lithiating Li layer. Correspondingly, we report that the pre-lithiation should be a general treatment which can be employed on many transition-metal di-chalcogenides to improve their storage capacities and charge-discharge performance in Li ion batteries. In addition, we propose that the pre-lithiated VS2 may serve as an outstanding anode material in LIBs. [ABSTRACT FROM AUTHOR]

The aim of this work is to characterize the seed oil of Aleurites moluccana and to develop a new formulation based on this oil (noted as "ALM"), which was used as a green corrosion inhibitor for iron in acidic solution. The fatty acid composition was determined using the chromatography gas GC/MS analysis. The Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements were carried out for different concentrations of the ALM formulation, immersion times and rotation speeds. The surface analyses was performed by scanning electron microscopy (SEM) coupled with the energy dispersive X-Ray analysis (EDX). The results showed that the seeds oil of Aleurites moluccana was principally composed of unsaturated fatty acids (Oleic, Linoleic and Linoleinic acids) reached a value of 88%. The inhibition efficiency increases with increasing of concentration to attain a value of 97% at 250 ppm of the ALM formulation and acts as a mixed type inhibitor. This efficiency is reinforced by increasing immersion time and the rotation speeds values of the working electrode. [ABSTRACT FROM AUTHOR]

A simple and highly selective electrochemical method for the investigation of catechol (CC) and hydroquinone (HQ) was developed on the surface bare carbon paste electrode (BCPE) modified with electropolymerized thin film of o-Phenylenediamine (o-PD) by using cyclic voltammetric technique. Electrochemical measurements were carried by using both cyclic voltammetric (CV) and differential pulse voltammetric (DPV) techniques at poly(o-PD) modified carbon paste electrode (MCPE). The proposed modified electrode shows adsorption-controlled process and exhibited a good limit of detection for CC and HQ was 1.1 and 2.1 µM respectively. In order to study the selectivity of the electrode, interference study was carried out by using DPV technique. Therefore, poly(o-PD)/MCPE showed excellent electrocatalytic behavior for the simultaneous electrochemical investigation of CC and HQ. [ABSTRACT FROM AUTHOR]

In the concept of deep geological repository for High Level Wastes, the chemical elements present in the media are expected to impact the long-term behavior of the glass. The effects of Ca, K, and Cs on International Simple Glass glass alteration are compared through long-term experiments (180–500 days). These elements limit glass alteration by their incorporation into the gel layer. The limiting mechanisms driving glass alteration appear to be mainly diffusive, at least during the first six months. The three cations are not equally efficient in limiting glass alteration: the effects of Ca are stronger than those of Cs and K. Multi-element experiments show that the effects of these elements are additive and proportional to the quantity of each element incorporated. When they play the role of charge compensator in the gel network, their incorporation is competitive and follows the order Ca ≫ Cs > K. In addition, when Ca is added to the solution in excess, the quantity of elements incorporated into the gel layer is higher than the amount required for charge compensation. The incorporation of Ca in the gel nanopores as calcium carbonate could explain this phenomenon. These processes could slow the transport phenomena through the gel and enhance its protective properties. [ABSTRACT FROM AUTHOR]

The characterisation of passive oxide films on heterogeneous microstructures is needed to assess local degradation (corrosion, cracking) in aggressive environments. The Volta potential is a surface-sensitive parameter which can be used to assess the surface nobility and hence passive films. In this work, it is shown that the Volta potential, measured on super duplex stainless steel by scanning Kelvin probe force microscopy, correlates with the electrochemical properties of the passive film, measured by electrochemical impedance spectroscopy and potentiodynamic polarisation. Natural oxidation by ageing in ambient air as well as artificial oxidation by immersion in concentrated nitric acid improved the nobility, both reflected by increased Volta potentials and electrochemical parameters. Passivation was associated with vanishing of the inherent Volta potential difference between the ferrite and austenite, thereby reducing the galvanic coupling and hence improving the corrosion resistance of the material. Hydrogen-passive film interactions, triggered by cathodic polarisation, however, largely increased the Volta potential difference between the phases, resulting in loss of electrochemical nobility, with the ferrite being more affected than the austenite. A correlative approach of using the Volta potential in conjunction with electrochemical data has been introduced to characterise the nobility of passive films in global and local scale. [ABSTRACT FROM AUTHOR]

Currently, there is great interest in using solid electrolytes to develop resistive switching based nonvolatile memories (RRAM) and logic devices. Despite recent progress, our understanding of the microscopic origin of the switching process and its stochastic behavior is still limited. In order to understand this behavior, we present a statistical 'breakdown' analysis performed on Cu doped Ge0.3Se0.7 based memory devices under elevated temperature and constant voltage stress conditions. Following the approach of electrochemical phase formation, the precursor of the 'ON resistance switching' is considered to be nucleation - the emergence of small clusters of atoms carrying the basic properties of the new phase which forms the conducting filament. Within the framework of nucleation theory, the observed fluctuations in the time required for 'ON resistance switching' are found to be consistent with the stochastic nature of critical nucleus formation. [ABSTRACT FROM AUTHOR]

Conducting polymer technology doped with nanodiamond particles enhances processability, tractability, electrical, mechanical, electrochemical, optical, thermal, and other essential physical properties. This review outlines some major conducting polymer/nanodiamond nanocomposites advances obtained with major conjugated polymers such as: polyaniline, polypyrrole, polythiophene, and polythiophene derivatives. Moreover, this article concisely and inclusively discusses how important conducting polymer nanocomposites are for supercapacitor, actuator, solar cell, corrosion protection, and biomedical fields. Finally, challenges and perspectives are deliberated for viable future high performance materials. [ABSTRACT FROM AUTHOR]

Lithium-ion (Li-ion) batteries have been used in a wide variety of applications, ranging from portable electronics to electric vehicles. During repetitive charging and discharging, a battery's capacity fades due to electrochemical reactions such as solid electrolyte interphase growth. Li-ion batteries reach an end-of-life (EOL) point, after which using them is not recommended. However, some unhealthy batteries reach their EOL sooner than expected. A qualification test is usually conducted to evaluate the reliability of Li-ion batteries and classify unhealthy batteries, but this test requires several months. This paper develops a data-driven method to reduce the qualification time by detecting anomalies before EOL. This method detects an anomaly in the capacity fade curve of unhealthy batteries based on their capacity fade trend. Since the developed method detects anomalies of unhealthy batteries before EOL, the method is effective in reducing the time for the qualification test of Li-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract Detailed knowledge regarding sensor based technologies for the detection of food contamination often remains concealed within scientific journals or divided between numerous commercial kits which prevents optimal connectivity between companies and end-users. To overcome this barrier The End user Sensor Tree (TEST) has been developed. TEST is a comprehensive, interactive platform including over 900 sensor based methods, retrieved from the scientific literature and commercial market, for aquatic-toxins, mycotoxins, pesticides and microorganism detection. Key analytical parameters are recorded in excel files while a novel classification system is used which provides, tailor-made, experts' feedback using an online decision tree and database introduced here. Additionally, a critical comparison of reviewed sensors is presented alongside a global perspective on research pioneers and commercially available products. The lack of commercial uptake of the academically popular electrochemical and nanomaterial based sensors, as well as multiplexing platforms became very apparent and reasons for this anomaly are discussed. Highlights • A repository for food contaminant detection providing expert advice was created. • The database facilitates performance comparison for stakeholders in the food industry. • Potential of nanomaterials and electrochemistry has not bridged the Valley of Death. • Virtually no multiplexing has been incorporated in commercially available kits. • Novel systems are expected to become user-friendly, portable and quantitative. [ABSTRACT FROM AUTHOR]

Abstract In this study, a dual-type responsive electrochemical biosensor was developed for the quantitative detection of α2,6-sialylated glycans (α2,6-sial-Gs), a potential biomarker of tumors. The gold nanorods (AuNRs), which exhibited great specific surface area, as well as good biocompatibility, was synthesized by the way of seed growth method. Furthermore, a biotin-streptavidin (biotin-SA) system was introduced to improve the immunoreaction efficiency. Accordingly, a label-free biosensor was fabricated based on AuNRs-SA for the quick detection of α2,6-sial-Gs by recording the signal of differential pulse voltammetry (DPV). Furthermore, to expand the ultrasensitive detection of α2,6-sial-Gs, a carboxylated single-walled carbon nanohorns/sulfur-doped platinum nanocluster (c-SWCNHs/S-PtNC) was synthesized for the first time as a novel signal label, which showed an excellent catalytic performance. The usage of c-SWCNHs/S-PtNC could significantly amplify the electrochemical signal recorded by the amperometric i-t curve. Herein, a sandwich type biosensor was constructed by combining the AuNRs-SA on the electrode and c-SWCNHs/S-PtNC (signal amplifier). The label-free biosensor possessed a linear range from 5 ng mL−1 to 5 μg mL−1 with a detection limit of 0.50 ng mL−1, and the sandwich-type biosensor possessed a wide linear range from 1 fg mL−1 to 100 ng mL−1 with a detection limit of 0.69 fg mL−1. Furthermore, the biosensor exhibited excellent recovery and stability, indicating its potential for use in actual samples. Highlights • A dual-type responsive electrochemical biosensor was fabricated for the first time to detect α2,6-sial-Gs. • A multifunctional composite of c-SWCNHs/S-PtNC was synthesized for the first time as a signal amplification module. • M-APBA was applied to the biosensor as a novel α2,6-sial-Gs molecular recognition ligand for the first time. [ABSTRACT FROM AUTHOR]

Abstract Developing low-cost, portable and simple analysis tools is of vital importance for food safety point-of-care testing. Therefore, herein, a new low-cost, simple to fabricate, disposable, electrochemical mast cell-based paper sensor is proposed and developed to sensitively determine the major milk allergen casein. Then, a graphene (GN)/carbon nanofiber (CN)/ Gelatin methacryloyl (GelMA) composite material with high conductivity and good biocompatibility was modified on the cell-based paper sensor to improve the electrical conductivity and provide a sensing recognition interface for the immobilization of rat basophilic leukemia (RBL-2H3) mast cells. The cyclic voltammetry and differential pulse voltammetry measurement of the mast cells in the paper sensor revealed an irreversible anodic peak, whose peak current is proportional to the number of cells in the range from 1 × 102 to 1 × 108 cells/mL. For the milk allergen detection tests, mast cells exposed to the casein caused a significant reduction in the current signal, displaying an inverse dose-dependent relationship. The developed cell sensor exhibited a range of linearity between 1 × 10−7 and 1 × 10−6 g/mL of casein with a detection limit of 3.2 × 10−8 g/mL and a great reproducibility and selectivity. The electrochemical responses obtained using the cell-based paper sensor were well consistent with the conventional detection assay, with good stability and reproducibility. Therefore, a simple and novel electrochemical method for food allergens detection was developed, demonstrating its potential application in the food safety determination and evaluation. Highlights • An electrochemical cell sensor was first reported based on paper platform. • Carbon nanofiber/graphene/GelMA composite was prepared to fabricate the sensor. • Low detection limit (3.2 × 10−8 g/mL) for casein was achieved using the present sensor. [ABSTRACT FROM AUTHOR]

Abstract ZnO/activated semicoke (ASC) desulfuriser was synthesised by electrochemical deposition. The obtained samples were characterised by Brunauer–Emmett–Teller analyses, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray fluorescence spectrometry analyses. The effects of deposition temperature on the morphology of ZnO on the ASC surface were investigated. Desulphurisation capability of the ZnO/ASC desulfuriser was assessed in a fixed-bed reactor and the desulphurisation mechanism was discussed. Results revealed that the loaded substance on ASC was pure ZnO. In addition, the quality of the ZnO crystal gradually improved from sheet to tube structure with increasing temperature. The desulphurisation performance of the desulfuriser was gradually enhanced as the deposition temperature increased. Graphical abstract Image 1 Highlights • ZnO/ASC desulfuriser was prepared by electrochemical deposition. • The morphology of ZnO on the ASC surface was largely influenced by the deposition temperature. • The formation mechanism of the ZnO/ASC was discussed. • ZnO/ASC showed higher desulphurisation capability than ASC. [ABSTRACT FROM AUTHOR]

Abstract Corrosion in human body can cause changes in materials structure and release of undesirable products which may bring about complications such as toxicity and inflammation, and jeopardize the mechanical stability of the prosthesis. In biomaterials engineering, attempt has been made on design and manufacture of implant materials with less corrosion, and reduced complications. In the present study, corrosion characteristics of titanium-alumina composites (25 vol% and 50 vol% Al 2 O 3) fabricated by spark plasma sintering were analyzed by polarization and electrochemical impedance spectroscopy. Physiological Ringer's solution was used as corrosion medium. The corrosion experiments were conducted in two time intervals. Pure titanium was also fabricated and analyzed for comparison. Furthermore, the samples were immersed in Ringer's solution for about 50 days and then characterized by scanning electron microscope (SEM). From the results of corrosion tests, it was indicated that pure Ti and the Ti-25% Al 2 O 3 had fully passive behavior and experienced breakdown at high voltage in the test potential region. The composite with 25% Al 2 O 3 content also showed superior corrosion resistance. The SEM images of the samples after long time immersion revealed both corroded regions and deposition zones on the surfaces. Highlights • Corrosion characteristics of titanium-alumina composites were investigated in physiological Ringer's solution. • Electrochemical testing methods were polarization and electrochemical impedance spectroscopy. • The performance of these composites after long time exposure in physiological Ringer's solution was also studied. • Composite with 25% Al 2 O 3 content showed superior corrosion characteristics. • After long time immersion both corroded regions and mineral deposition zones were observed on the surfaces of the samples. [ABSTRACT FROM AUTHOR]

An electrochemical route has been employed to prepare undoped and Se-doped SnS thin films. Six samples including undoped and Se-doped SnS thin films were deposited on the fluorine-doped tin oxide glass substrate. An aqueous solution containing 2 mM SnCl2 and 16 mM Na2S2O3 was used in the electrolyte. Different Se-doped SnS samples were prepared by adding the various amounts of 4 mM SeO2 solution into the electrolyte. The applied potential (E), time of deposition process (t), pH, and bath temperature (T) were kept at − 1 V, 30 min, 2.1, and 60°C, respectively. After the completion of the deposition process, x-ray diffraction (XRD) and transmission electron microscopy (TEM) were utilized to characterize the deposited thin films. XRD patterns clearly showed that the synthesized undoped and Se-doped SnS thin films were crystallized in the orthorhombic structure. Using Scherrer's method, the crystallite size of deposited thin films is calculated. In addition, the crystallite size and lattice strain have been estimated using the modified form of the Williamson-Hall (W-H) method containing a uniform deformation model, a uniform deformation stress model, a uniform deformation energy density model, and by the size-strain plot method (SSP). The shape of SnS crystals was spherical in TEM images. The results showed that there was a good agreement in the particle size obtained from the W-H method and the SSP method with TEM images. [ABSTRACT FROM AUTHOR]

In the present work, flower-like mesoporous MoS2 has been synthesized via a one step hydrothermal approach. The electrochemical performance of synthesized flower-like MoS2 nanostructures for supercapacitor applications has been probed via cyclic voltammetry, galvanostatic charging-discharging and electrochemical impedance spectroscopy in 1 M H2SO4 (acidic electrolyte), 1 M Na2SO4 (neutral electrolyte) and 2 M KOH (basic electrolyte) electrolytes using a three electrodes configuration. On the basis of electrochemical measurements, it has been observed that as-prepared flower-like MoS2 exhibits specific capacitances of 225 F g−1, 205 F g−1 and 123 F g−1 in 1 M H2SO4, 1 M Na2SO4 and 2 M KOH electrolytes at 1 A g−1, respectively. Moreover, for the MoS2 electrode the diffusion coefficients in 1 M H2SO4, 1 M Na2SO4 and 2 M KOH electrolytes are found to be 8.52 × 10−10 cm2 s−1, 5.41 × 10−10 cm2 s−1 and 8.35 × 10−10 cm2 s−1, respectively. Further, the relaxation time constants (τ), which represent how quick a supercapacitor system can deliver stored energy at high power, are found to be 37 ms, 77 ms and 1.49 s for as synthesized MoS2 in 1 M H2SO4, 1 M Na2SO4 and 2 M KOH electrolytes, respectively. However, the capacity retention/coulombic efficiency of a MoS2 electrode in 1 M H2SO4, 1 M Na2SO4 and 2MKOH is found to be ∼ 30%/89%, 89%/94% and 86%/92%, respectively, after 1000 successive cycles at 2 A g−1. Our results suggest that a pristine flower like MoS2 is a good material to design a high performance supercapacitor device, which exhibits stable electrochemical performance in 1 M Na2SO4 electrolytes. The detailed electrochemical behavior of as synthesized samples has been thoroughly described in this paper. We believe our findings would be helpful in the designing of flower-like MoS2 based practical high performance supercapacitor devices. [ABSTRACT FROM AUTHOR]

The influence of chloride ion on the corrosion of metal under coating with scratch defects was researched by wire beam electrode (WBE) technology and electrochemical impedance spectroscopy (EIS) technology. The results showed that the current of metal surface could be characterized by the WBE technology. In the case of scratches on the coating, the location of the damage always showed an anodic current, and the cathodic reaction took place adjacent to the damaged location. The cathode area surrounded the defect and migrated to the far end over time. With the increase of Cl- concentration, the corrosion reaction speeded up, the rate of cathode migration also increased, and the speed of coating stripping did as well. Combined with electrochemical impedance spectroscopy, uniform laws were obtained. [ABSTRACT FROM AUTHOR]

Abstract We have successfully synthesized three derivative of phenylglycine by Schotten-Baumann method denoted as 2-[(4-methylbenzoyl) amino] phenyl acetic acid (B-Me), 2-(benzoyl amino) phenyl acetic acid (B-H) and 2-[(4-chlorobenzoyl) amino] phenyl acetic acid (B-Cl). Afterward, dealing with improving electrochemical properties of the poly ortho aminophenol (POAP), we fabricated POAP/B-Me, POAP/B-H and POAP/B-Cl films through electro-polymerization of POAP by employing of N-benzoyl derivatives of phenylglycine to consider as the active electrode for SCs. Analysis of electronic wave function (DFT-method) results show that the atomic-scale electronic properties are generally depend on the bonding and electronic molecular structures and electron donating group on the N-benzoyl derivatives has main important effect rather than electron withdrawing group. The electrochemical properties of electrodes and the capacitive behavior of the resulting capacitors were systematically studied using cyclic voltammetry (CV), ac impedance and constant current charge–discharge tests. The specific capacitance of POAP/B-Me electrode was exhibited as high as 614.3 F/g, in comparison with a value of 261 F/g for POAP film. These results make POAP/B-Me it a promising candidate for supercapacitor applications. Highlights • Developing a simple and green route for synthesis of composite of POAP • Improving electrochemical properties of the poly ortho aminophenol • Presenting a novel and efficient composite materials for electrochemical redox capacitors [ABSTRACT FROM AUTHOR]