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As a popular direction of research in micro-energy storage devices, improving the comprehensive performance of all-solid-state planar on-chip micro-supercapacitors (MSCs) has received increasing attention. Graphene quantum dots (GQDs) are a new type of nano-scale electrode materials that can improve the electrochemical performance of devices. In addition, the doping of nitrogen/oxygen heteroatoms can further improve the electrochemical activity of the electrode materials. In this paper, nitrogen-oxygen co-doped graphene quantum dots (NO-GQDs) were used as electrode materials, and a modified liquid-air interface self-assembly method was used to fabricate the electrode films. Finally, the MSCs with narrow interdigital electrode configuration were prepared by photolithography with an electrode width/interdigital gap of 3 μm/1 μm. The prepared MSCs have excellent electrochemical performance, including an area capacitance of 150.63 μF cm−2, an energy density of 20.92 nWh cm−2, a power density of 175.49 μW cm−2, a relaxation time constant of 3.53 μs, and a capacitance retention of 90.42%. As shown by the results, the combination of NO-GQDs and narrow interdigital electrode configuration provides a significant improvement in the comprehensive electrochemical performance of the all-solid-state planar on-chip MSCs. [ABSTRACT FROM AUTHOR]

As a soluble dietary fiber, pectin has the functions of lowering cholesterol, reducing weight and improving human immunity. However, nowadays, many studies have been reported on the extraction of pectin, but few on its quantitative analysis. In this paper, graphene modified copper foam and copper sheet were used as working electrodes, respectively. Pt electrode as counter electrode and Ag/AgCl (saturated KCl solution) electrode was used as reference electrode to build electrochemical detection system. The electrochemical responses to pectinose solution were measured by voltammetry (CV) and chronoamperometry (i-t). The detection data were analyzed to develop pectinose quantitative analysis model. Results indicated that the proposed method could determine pectinose concentration in solution, and graphene modified copper foam presented better responses. The sensitivity was 0.68851A cm−2 mmol/L, the detection limit was 0.24825 mol/L. This method presents some advantages including fast response, easy operation, and low cost. It provides a new method for pectinose quantitative detection. [ABSTRACT FROM AUTHOR]

In this paper, a flexible self-supported electrode based on the porous composite of NiS2 and Ti3C2Tx grown on carbon cloth (NiS2/Ti3C2Tx-CC) was designed and synthesized. Due to the introduction of highly conductive and flexible Ti3C2Tx, the NiS2/Ti3C2Tx-CC electrode achieves a 1.4-fold increase (1214 C g-1 at 2 A g-1) in the specific capacity, a 1.3-fold increase in the rate capability (63% of capacity retention with the current density increases from 2 to 20 A g-1), and a 2.0-fold increase in the cyclic stability (∼83% of capacity retention at the current density of 20 A g-1 after 2000 charge–discharge cycles) compared with the NiS2-CC electrode. Meanwhile, there is no obvious capacity attenuation at the bending angle of 180°, indicating the prominent flexibility of the NiS2/Ti3C2Tx-CC electrode. Accordingly, an all-solid asymmetric supercapacitor (ASC) is fabricated, which exhibits a high energy density of 57.55 Wh kg-1 at the power density of 800 W kg-1. Furthermore, ∼97% of initial capacity is maintained at the current density of 5 A g-1 after 1000 charge–discharge cycles, indicating the good cycling stability. These satisfactory electrochemical behaviors can be also ascribed to the introduction of Ti3C2Tx, which can facilitate the rapid electron transport at the interface of the composite and maintain the outstanding mechanical integrality of the electrode during charge–discharge processes. [ABSTRACT FROM AUTHOR]

LiFePO4 is a promising cathode material for lithium-ion batteries due to its excellent rate capability and superior safety. However, its relatively low energy density makes the research efforts towards another olivine structure material LiMnPO4, which exhibits higher energy density and operating voltage. Nevertheless, LiMnPO4 does not show the remarkable electrochemical performance attributing from the low electronic/ionic conductivity. To solve the problems, a facile solvothermal method is used to successfully synthetise the LiMn1-xFexPO4/C with different Fe/Mn ratio (LMFP/C) nanoparticle in this paper. The length of the obtained LiMn1-xFexPO4/C is less than 200 nm. Owing to the doping of iron and the nano-structure, the LiMn0.5Fe0.5PO4/C nanoparticle exhibits high discharge capacities of 153.6, 143.2 and 134.5 mAh g−1 at rates 0.1 C, 1 C and 5 C, respectively. Furthermore, the effects of pH on the morphology evolution and electrochemical performance have been also investigated in detail. [ABSTRACT FROM AUTHOR]

In this paper, a wet chemical method is used to coat LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode material by Li2O-2B2O3 (LBO) layer for Lithium-ion batteries (LIBs). For performance optimization, the effects of different contents (thicknesses) of LBO coating layers on NCM811 particle surface on the morphologies, structures, compositions, and electrochemical properties of the corresponding LIBs are studied using XRD, SEM, TEM, and electrochemical measurements. Coin LIBs are assembled with such coated NCM811 cathode materials for performance validation. Results show that LBO coating layer does not change the original lattice structure of the bulk material, it can only adhere to the surface of the bulk material. After coating, NCM811 shows a good crystallinity and the ordered layered structure. TEM images show that the thickness of LBO coating is increased with increasing LBO content, and that the appropriate LBO coating thickness and uniform coating state are conducive to the improvement of the electrochemical properties of NCM811 cathode materials. Particularly, NCM811 with LBO coating content of 1000 ppm shows the best performance compared to other coating contents. In this case, the coating thickness is relatively uniform, which is about 40～100 nm, giving a good first charge-discharge capacity of 214.1mAh/g, and a high Coulomb efficiency of 90.06%. After 50 cycles, the capacity retention rate of LIBs still keeps as high as 99.64%. Therefore, LBO coating can improve the performance of NCM811 and then the lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The use and abuse of prescription and illicit drugs are on the rise worldwide and as a result residue of these drugs and their metabolites are continually being disposed into the environment through sewage system and other means. Therefore, this paper reports on the development of a cost-effective, simple and sensitive approach that involved the fabrication of an electrochemical sensor from exfoliated graphite (EG) and gold nanoparticles (AuNPs) for the detection of selected psychoactive drugs in water. The fabricated electrochemical sensor was characterized using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS) to ascertain its surface morphology characteristics and cyclic voltammetry (CV) for ascertaining the redox potential peak. The EG-AuNPs sensor was able to detect cocaine in water with limit of detection (LOD) and limit quantification (LOQ) of 0.82 and 2.74 µg/L, respectively under the pH of 12.25. The sensor was extended on other psychoactive drugs (methylphenidate, amphetamine and heroin) and one metabolite (6-acetylmorphine) to examine its applicability. The drugs were distinctively detected, and thus making EG-AuNPs electrode a possible alternative sensor for electrochemical detection of psychoactive drugs and their metabolites in synthetic and real water samples. [ABSTRACT FROM AUTHOR]

In this paper, experiments in Electrochemical Micromachining (ECMM) were conducted to produce micro-holes of high aspect ratio using a cathode 'Polymer Graphite Electrode' (PGE). The effect of electrochemical dissolution of ASTM A240 type 304 stainless steel is comparatively studied using cryogenically treated PGE (CTPGE) tool and non-treated PGE tool (NTPGE) that owes to enhance the overall quality of micro-hole produced, which is assessed on the basis of the most imperative output responses namely the material removal rate (MRR), and the Overcut (Oc) in relation to the predominant input process parameters namely, Voltage (S1), Electrolytic concentration (S2) and the Duty cycle (S3). Response surface modeling based on Box-Behnken (BB) DoE was used to obtain the corresponding responses for the process factors. Numerical models were developed to study and effects of process factors individually and their interactional effect. ANOVA was used to study the statistical significant process factors. The outcome of the multi-objective optimization based on cuckoo search algorithm (MOCS) was found to be enhanced, owing to better surface characteristics of the workpiece machined using the CTPGE tool. The effect of the micro spark and stray current have dwindled when using CTPGE electrode that can be visually seen via SEM. [ABSTRACT FROM AUTHOR]

In this paper, Fe–MnO2/RGO active materials were prepared by hydrothermal method. The phase composition, microstructure and electrochemical properties of the prepared Fe–MnO2/RGO composites were characterized by XRD, SEM, TEM, and electrochemical analysis. The results show that, the adding of Fe ions improves capacitive performance of the MnO2. It was found that the specific capacitance of Fe–MnO2 was 119 F·g−1 when the molar ratio was 4 mol%. Here, the characterizations show that the RGO plays an important role on electrochemical performances of Fe–MnO2. We find that there is an obvious enhancement in the capacitance performances of Fe–MnO2/RGO, which is improved from 119 to 144 F·g−1. [ABSTRACT FROM AUTHOR]

In this paper, we report solution processable cathode buffers composed polyethyleneimine (PEI) and C60 fullerene or PCBM for OPV. A PEI layer was formed on an ITO surface by dip coating, followed by the immobilization of C60 or PCBM on ITO/PEI surface by the chemical reaction between an aliphatic amine and fullerene. They were used for cathode buffers in OPVs and the device performance was improved compared with the device without the buffer. The improvement can be attributed to the lowered work function (WF) by the dipole formed by PEI and ITO. The parameters in the equivalent circuit with a single diode tells us that the buffers act as electric bilayer lowering the effective voltage on the diode. [ABSTRACT FROM PUBLISHER]

The effect of different species of cathode on the performance of organic light-emitting diodes under direct current drive has been investigated in this paper. The organic light-emitting diode using LiF/Al and LiF/MgAg layer as cathode has been fabricated, and the luminance of device with cathode structure of LiF/MgAg was found to realize higher efficiency. The performance of the device was found to be improved greatly due to efficient electron injection from MgAg cathode. Moreover, a configuration of LiF/MgAg/IZO (indium zinc oxide) was developed, finding that both the top-emitting intensity and the bottom-emitting intensity achieve very-high luminance, and in this basis, transparent OLEDs with the extremely high-luminance of about 100,000 cd/m2has been realized, which is considered as the highest luminance among the previous works. [ABSTRACT FROM AUTHOR]

This paper describes improvements in the considered parameters of micro-geometry: flank surface topology and finishing productivity of 20MnCr5 alloy steel straight bevel gears through their finishing by pulsed electrochemical honing (PECH) process. Effects of three most important parameters of PECH process, namely applied voltage, electrolyte composition, and electrolyte concentration were investigated to identify their optimum values. Pre-identified values of other PECH parameters and an aqueous mixture of NaCl and NaNO3as an electrolyte were used in the present work. Errors in pitch (i.e., single pitch error, adjacent pitch error, and cumulative pitch error) and runout were used to evaluate micro-geometry of the straight bevel gears while volumetric material removal rate was used to judge the finishing productivity of the PECH process. Topology of the gear tooth flank surface and microstructure of the best-finished bevel gears were also studied. The results revealed considerable improvements in the micro-geometry, flank surface topology, and microstructure of the bevel gears finished by PECH. Applied voltage of 8 V, electrolyte composition of 75 wt.% NaCl + 25 wt.% NaNO3,and electrolyte concentration of 7.5 wt.% were identified as the optimum values to achieve simultaneous improvement in all the considered responses. [ABSTRACT FROM AUTHOR]

In real-world applications of electrostatic adhesion technology, the electrostatic adhesion force decreases when the electrode panel slides or rotates relative to the attachment substrate due to an external disturbance. However, little work has been done to study this phenomenon. This paper presents a model and analysis method to evaluate the electrostatic adhesion performance considering a rotary disturbance between the electrode panel and the attachment substrate. First, dynamic variations of the electric fields for any point on the attachment substrate are analysed. Then the decrease in the electrostatic adhesion force is explained based on the analysis results and our previous work. The analysis results and explanations are experimentally validated on three different attachment substrates. The fundamental cause of the decrease in adhesion force is the loss of the lined layer polarization due to the rotary disturbance. The results provide a good explanation to the phenomenon and make the existing electrostatic adhesion theory more self-consistent. [ABSTRACT FROM PUBLISHER]

Li4Ti5O12 (LTO) is one of the most promising high-power anodes for lithium ion batteries, but its large-current performance is still undermined due to relatively poor ion/electron transfer. In this work, we report a powerful hydrothermal method for fabrication of highly porous binder-free Li4Ti5O12 films, which show hierarchical structure composed of interconnected primary nanoparticles of 50-100 nm and secondary nanowalls. The lithium ion storage performance of designed Li4Ti5O12 films is thoroughly studied and demonstrated with excellent high-rate performance. The as-prepared Li4Ti5O12 films exhibit a high specific capacity of 146 mAh g-1 at the current density of 2 C. In view of good structural stability, a notable cycling stability is verified with a specific capacity of 130 mAh g-1 after 5000 cycles at 2 C. Our method provides a novel route for synthesis of other advanced anodes for application in the field of ultrafast energy storage. Highly porous binder-free Li4Ti5O12 films are synthesised via a hydrothermal method and exhibit a noticeable high-rate electrochemical performance as the anode of lithium ion batteries. [ABSTRACT FROM AUTHOR]

An attempt was made, at the laboratory level, to apply new external anode of an electrochemical chloride extraction (ECE) system based on Ni chemical deposition on concrete specimen surface. The procedure relied on electroless bath chemical deposition to apply anodic electrode of nickel on concrete samples. The procedures and experimental conditions of the nickel deposition on the concrete were carefully addressed. The influence of Ni films characteristics, as external anode in ECE system, on the chloride electrochemical extraction (ECE) process was investigated. ECE performance in comparison with the use of traditional titanium mesh was investigated. Several analytical tools were applied to both characterise the obtained Ni films and to study the efficiency of ECE process. These include scanning electron microscopy (SEM) to explore the morphology of the nickel films and the electron probe micro analysis (EPMA) that was performed simultaneously with SIM to gain composition analysis of the samples. Finally, chloride ion selective electrode (ISE) analytical tool was applied to study the efficiency of ECE process. [ABSTRACT FROM AUTHOR]

We have found approaches to the synthesis of cheap near-stoichiometric lithium nickelate (LiNiO2). The resulting phases have been identified by X-ray phase analysis. Obtained materials have been studied by spectrometric method; electron microscopy; BET method; impedance spectroscopy. A technological scheme has been developed, the optimal conditions for the combined synthesis of lithium nickelate close to the stoichiometric composition Li0.98Ni1.02O2 have been determined. We have proved that nanosized samples with a well-developed surface form during such a synthesis. We have determined that the electrochemical characteristics of the samples correspond to those of lithium nickelate used in commercial electrochemical cells. [ABSTRACT FROM AUTHOR]

In this study, Ce and Mn co-doped SnO2–Sb electrode was prepared onto a Ti/TiO2 nanotubes surface. The nanostructure of the novel electrode was characterised by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS), and specific techniques were used to study the electrochemical characteristics of the electrode. SEM analysis results showed that TiO2 nanotubes could reduce the crack morphology and provide a larger surface area for loading the electrochemically active material. EDS analysis showed that Ce and Mn were doped into the electrode successfully. Under optimised conditions, the electrode prepared with Sn:Sb:Ce:Mn mole ratio of 100:10:3:3 has the best electrocatalytic performance. Ethylene glycol was used as the solvent in cerium-manganese co-doped Ti/TiO2–NTs/TiO2–SnO2–Sb electrode. Ce–Mn co-doped TiO2NTs/SnO2–Sb electrode has a high oxygen evolution potential of 1.79 V (vs. SCE) and a lower charge transfer resistance. The decolourisation extent of 30 mg L−1 methylene blue wastewater reaches 98.5% within 30 min. Finally, the main intermediates were identified by gas chromatography-mass spectrometer (GC-MS), and possible pathways for dye degradation were proposed. This study opens a door to the rapid electrochemical decoloursation treatment of wastewater by using an easily obtainable multi-metal co-doped electrode. [ABSTRACT FROM AUTHOR]

A high specific capacity spherical Li4Ti5O12 anode material of Lithium-Ion battery was successfully synthesized by a high-temperature solid-phase method consisting of ball milling, spray drying and calcination processes. Its suitable reaction conditions were explored by the orthogonal experiment method, and the effect of glucose addition on the morphology and electrochemical performance of Li4Ti5O12 was studied. The addition of glucose could change the surface structure of Li4Ti5O12, improve its conductivity, therefore enhance its electrochemical performance. The prepared lithium titanate represents a superior specific capacity of 163 mAh·g−1 at 0.2 C rates, approximately 65 mAh·g−1 under 10 C rates, and the capacity retention rate of sample remained 97.55% after 100 cycles of charging/discharging process. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor for sensitive and selective detection of hydroquinone (HQ) was developed using graphene/iridium(III) dimer complex composite modified glassy carbon electrode (graphene/Ir(III) complex/GCE). The composite was characterised by field emission scanning electron microscopy, energy dispersive X-ray microanalysis, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The graphene/Ir(III) complex/GCE has provided higher surface area which was good for catalytic activity and enhanced electrical conductivity that was then examined using differential pulse voltammetry, cyclic voltammetry, and square wave voltammetry. At optimal condition, HQ has been sensitively detected in the ranges of 100–1.5 µM and 1.5–0.05 µM with good sensitivity of 1120.64 μA/mM/cm2 and low detection limit of 1.1 nM (S/N = 3). The graphene/Ir(III) complex/GCE sensor presented the performance advantages of good reproducibility, repeatability, stability and selectivity. The prepared electrode was further applied to detect HQ in real-life water samples, which exhibit the acceptable recovery. [ABSTRACT FROM AUTHOR]

Core–shell Li(Ni, Mn)xOy thin film has been deposited onto a (111) single-crystal Nb-doped SrTiO3 substrate by pulsed laser deposition. The thin film is ∼350–400 nm thick with a ∼60 nm-thick Ni-rich interface. The orientation relationship between the cubic Li(Ni, Mn)2 O4 spinel and distorted rhombohedral-layered Li(Ni, Mn)O2 phases and the substrates are [112] STO ||[112]Spinel and ( 1 ¯ 1 ¯ 1) STO ||( 1 ¯ 1 ¯ 1) Spinel; [112] STO ||[210] LiNiO2 and ( 1 ¯ 1 ¯ 1) STO ||(00 3 ¯ ) LiNiO2; and [112] Spinel ||[210] LiNiO2 and ( 1 ¯ 1 ¯ 1) Spinel ||(00 3 ¯ ) LiNiO2. The film–substrate interface is sharp, non-reactive and free of planar defects. The interfaces between spinel, rhombohedral-layered Li(Ni, Mn)O2 and the order–disorder domains are coherent and diffused. As the spacing between octahedral cations in the spinel phase and in the Li(Ni, Mn)O2 phase is different; these two phases could be distinguished by quantifying the spacings between two octahedrally located cations. The electro-chemical behaviour of the film is not likely to be optimum even with the intended phase composition and chemistry due to disordering in Li (Ni, Mn)O2 and unsuitable orientation of the phases. Understanding such structural details is a precursor to tailor the electro-chemical activity in Li(Ni, Mn)xOy. [ABSTRACT FROM AUTHOR]

We have synthesized new electrode material for the supercapacitor application. Polyoxovanadates (POVs) have been used for energy storage electrode materials due to their fast multi-electron redox properties. The formation of SDV/GO composites was confirmed using various analytical methods, e.g., Fourier transforms infrared spectroscopy (FTIR) and powder X-ray diffraction (XRD), followed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The composite electrode's electrochemical behavior was studied using a neutral 1 M sodium sulphate (Na2SO4) solution in three-electrode cyclic voltammetry (CV) system. The SDV/GO composite electrode showed a specific capacitance of 306 F/g for a scan rate of 5 mV/s and a corresponding energy density of 42.4 Wh/Kg. Galvanostatic charge/discharge exhibits a specific capacitance of 310 F/g with energy densities of 43.08 Wh/kg. Electrochemical impedance spectroscopy (EIS), which was used to investigate interface property, yielded a considerably higher power density of 172.41 KW/kg with an equivalent series resistance of 5 Ω. [ABSTRACT FROM AUTHOR]

Conductive boron-doped diamond (BDD), in addition to its superior material properties, offers many important advantages that make it an interesting material for electroanalytical studies. It has been considered as an excellent electrode material for electrooxidation of drug active compounds in their dosage forms or in biological materials due to its good physical and chemical properties. It contains not only the largest solvent working potential window compared to other electrode materials, but also it has low background and capacitive currents; lower problems with passivation and it has the ability to withstand extreme potentials, corrosive, and high temperature/pressure environments. The aim of this review is not only to provide a state-of-the-art of diamond electrochemistry but also to serve as a reference point for any researcher wishing to commence work with diamond electrodes and understand electrochemical data. Therefore, it is focused on the carbon-based materials, electrochemical properties of the BDD film electrode, its fundamental research, and its electrochemical pretreatment process are discussed in detail. In this case, there are important studies to show the effective BDD drug sensors for the detection and determination of drugs and the present review critically summarizes the available data in this field between 2015 and 2020. [ABSTRACT FROM AUTHOR]

A new silver(I) inorganic polymer, formulated as {[Ag4(H2ebidc) (NH3)4](H2O)2}n (H2ebidc = 2,2'-(ethane-1,2-diyl)bis(1H-imidazole-4,5-dicarboxylic acid), was synthesized and characterized by X-ray crystallography, elemental analysis and IR spectroscopy. The crystal analysis results showed that the four silver(I) ions were linked by the H2ebidc4− ligand to form a tetranuclear cluster subunit, and then a one-dimensional ring-to-ring chain was constructed through the Ag(I)-Ag(I) bonds between the cluster subunits. Electrochemical sensing performance of the Ag(I) inorganic polymer modified carbon paste electrode (CPE-Ag) for H2O2 was evaluated by chronoamperometry in 0.2 M phosphate buffer saline (PBS, pH = 6) at −0.2 V. The electrochemical H2O2 sensor CPE-Ag was found to lead to a linear response from 0.5 μM to 4.0 mM with a detection limit of 0.32 μM. Moreover, the sensor also revealed good anti-interference ability and stability. The above studies proved that Ag(I) inorganic polymers can be used as effective components of electrode materials for the electrochemical recognition of H2O2. [ABSTRACT FROM AUTHOR]

Surface modification of graphene and activated carbon through heat treatment has been used to increase the materials' electrical and optical properties for lithium-ion capacitor (LIC) applications. The surface modification techniques employed in this study emphasize introduction of an acidic group and a small number of lactonic and phenolic groups on graphite and activated carbon to facilitate their dispersion in aqueous media. In this research, lithium dispersion at high temperatures, the surface properties of the materials, and their electrochemical and optical properties are assessed. These include lithium dispersion and covalent attachment of functional groups. The effects of these surface modifications on the performance characteristics of dispersed nanocomposites were evaluated through several techniques (XRD, SEM, TEM, cyclic voltammetry, Mott-Schottky, BET, BJH, T-plot, pore size distribution, Boehm titration, and chronoamperometry). Especially, the highest oxidation peak corresponding to current value appeared at 0.0056 mA/cm2 current density and the lowest reduction peak value marked at 0.0002 mA/cm2, when the Li-G sample used to the FTO surface. The electrochemical stability of cathode materials was tested by 10 recycling tests, which the peak current drop decreased the peak profile became stable. The Li-dispersed graphite and activated carbon had synergistically upgraded electrochemical activity and superior cycling stability that were demonstrated in LIC. This research presented herein offers a promising route for the rational design of Li amounts and stable electrochemical reaction in LIC working mechanism. Surface modification with the introduction of an acidic group and a small number of lactonic and phenolic groups on graphite and activated carbon Lithium dispersion at high temperatures for the lithium amounts expansion for the cyclic stability The electrochemical stability of cathode materials with stable peak profile The rational design of Li amounts and stable electrochemical reaction in LIC working mechanism [ABSTRACT FROM AUTHOR]

Phthalocyanines are aromatic or macrocyclic organic compounds and attract great attention due to their numerous properties. They have many high-tech applications in different areas of the industry such as dyestuffs, thermal printing screens, photovoltaic solar cells, membrane catalytic reactors, semiconductor materials and gas sensors. In the last decade, electrochemical sensor studies have accelerated with the catalytic lighting. It plays a dominant role in the development and implementation of new generation sensors. The aim of this study is to review the electrochemical methods based on electrode modification with phthalocyanines and to shed light on new application areas of phthalocyanines. The focal point was based on the sensor applications of phthalocyanines in the determination of drugs, pesticides, organic materials and metals etc. by electrochemical methods. Experimental conditions and some validation parameters of the sensor applications such as metal phthalocyanine types, indicator electrodes, selectivity, working ranges, detection limits, and analytical applications were discussed. Consequently, this is the first review dealing with the applications of phthalocyanines in electrochemical sensors for the sensitive determination of analytes in a variety of matrices. [ABSTRACT FROM AUTHOR]

Three-dimensional electrochemical oxidation (3D-ECO) technology is considered as one of the most promising advanced oxidation processes for degrading refractory organic pollutants. However, the preparation of the particle electrodes (PEs) is a key factor for industrial applications. In this study, a new Al2O3-based PE was proposed for 3D-ECO system. The prepared PEs were characterized by scanning electron microscopy, energy-dispersive X-ray microscopy, and X-ray diffraction to examine their morphology, elementary composition, and amount of CuFe2O4 respectively. Experiments comparing different conditions showed that 3D-ECO system equipped with prepared PEs and persulphate (PS) was more efficient in degradingp-nitrophenol (PNP). Based on these results, the critical process parameters of the dosage of the PEs, initial PS concentration, and current density for 3D-ECO using the proposed PEs were examined. Under the optimized operations, the PNP removal rate reached 80.23% with a low electrical energy consumption of 3.97 kW h/mg PNP, which was significantly better than the 69.16% and 9.50 kW·h/mg PNP under conventional ECO process. Moreover, cycling experimental results indicated that the performance of the PEs had no declining trend during the 5 h test period, suggesting acceptable stability of the particles without particle damage or mass loss. These investigations provide a novel route for preparing high-efficiency PEs. [ABSTRACT FROM AUTHOR]

A carbon paste electrode (CPE) modified with a new bis(benzimidazole) dinuclear Ag(I) complex was developed as an electrochemical sensor to quickly and accurately identify hydrogen peroxide. The dinuclear Ag(I) complex, [Ag2(BBP)2(p-tso)2], was prepared by reaction of 1,3-bis(1H-benzimidazole-2-yl)propane (BBP) with p-toluenesulfonate (p-tso). The Ag(I) complex was studied by elemental analysis, IR and UV-Vis spectra, and single-crystal X-ray diffraction. The Ag(I) complex is a dinuclear metallacycle with twofold rotational symmetry in which two syn-conformational BBP are connected by two linearly coordinated Ag(I) ions. Each Ag(I) has three-coordinate T-shaped geometry. The electrochemical sensing performance of the Ag(I) complex modified carbon paste electrode (Ag-CPE) toward H2O2 was evaluated by cyclic voltammogram and chronoamperometry in 0.2 M phosphate-buffered saline (PBS, pH = 6). Linear relationships between the peak currents and the scan rates showed that the electrochemical reaction on Ag-CPE is controlled by dynamics. Moreover, the electrochemical sensor for H2O2 was found to have a linear response from 0.5 μM to 4.0 mM with a detection limit of 0.42 μM and also revealed good anti-interference ability and stability. These studies proved that the Ag-CPE can be used as an electrochemical H2O2 sensor. [ABSTRACT FROM AUTHOR]

Rechargeable lithium-ion batteries (LIBs), regarded as a promising power sources, have been widely applied in both electric vehicle and large stationary power supplies. As the most appealing potential anode material, Lithium titanate (Li4Ti5O12) used in LIBs offers the advantages of having negligible volume change, stable voltage plateau, relatively high theoretical capacity, high safety, and long operational life. However, a few shortages for Li4Ti5O12 battery applications are still remained, such as relatively low electronic conductivity and low tap density. Herein, an updated overview of the latest advances in Li4Ti5O12 research over the last 10 years is provided in in synthesis methods and modification methods for Li4Ti5O12-based anode materials. Additionally, recent progress of the synthesis of binder-free hybrid Li4Ti5O12 anodes for next-generation lithium-ion batteries is highlighted. Finally, future perspectives for further development of Li4Ti5O12-based electrodes also are pointed out from a scientific and an industrial point of view. [ABSTRACT FROM AUTHOR]

The increasing demand for compact and functional electronics has led to significant rise in research interest in the development of versatile energy storage systems. With this perspective notion, herein, we fabricated electrically conducting polymer-based flexible carbon cloth (CC) electrodes and assessed their electrochemical performance. Briefly, polyaniline nanofibers (Pani-NFs) and polypyrrole nanotubes (PPy-NTs) were synthesized by interfacial polymerization and reactive self-degrade template method, respectively. The physico-chemical properties of the as-synthesized nanostructured conducting polymers were characterized with the help of X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), field emission transmission electron microscope (FETEM) and Raman spectroscopy. The electrochemical performance of the Pani-NFs and PPy-NTs coated flexible CC electrodes was evaluated in 1 M H2SO4 electrolyte with a potential window of −0.2 to 0.8 V versus saturated calomel electrode (SCE). The Pani-NFs and PPy-NTs coated electrodes yielded the maximum areal capacitance of 0.79 and 0.74 F.cm−2, respectively at a constant discharge current density of 10 mA.cm−2, which was determined from the charge-discharge curve during the discharging period. The results demonstrate the potential of the nanostructured conducting polymer-based flexible electrodes for portable and wearable energy storage applications. [ABSTRACT FROM AUTHOR]

A novel membrane-electrode structure is conceived and prepared in this work, where a graphene-contained layer is constructed between anode catalyst layer and membrane, also the material composition in this layer is optimized to improve the performance of a direct methanol fuel cell (DMFC) with high-concentration fuel. The polarization test shows that the pristine graphene layer could reduce the methanol crossover, while causing a slight decrease in performance. After adding Nafion ionomer binder in the graphene layer, the peak power density of the electrode fed with 8 M methanol reaches 17.75 mW cm−2, which is increased by 12.36% and 82.69% compared with the conventional electrode and the electrode without any binder in the graphene layer, respectively. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) results show that for the graphene-contained layer including Nafion ionomer binder, the charge transfer resistance is only one-fifth of that without binder in the graphene layer, and the anode electrochemical active surface area (ECSA) is increased by 40.16%. These results indicate that the anode electrode with a graphene-contained layer using Nafion ionomer as the binder can effectively improve the cell performance with high-concentration fuel, which is beneficial to increase the energy density of a DMFC system. [ABSTRACT FROM AUTHOR]

An electrochemical sensor has been developed using Patton and Reeder's reagent which is electropolymerised on pencil graphite electrode (PR-PGE) for the selective and sensitive determination of Atenolol (ATN). The cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectra were used to check the analytical applicability of the proposed sensor for the investigation of ATN. To achieve better electrochemical response, the parameters such as pH, scan rate and electron transfer kinetics were determined. Under optimum experimental conditions, the linear calibration curve shows concentration linear range of 0.1–1.8 µM and the limit of detection 4.9 × 10−8 M. The proposed sensor shows better selectivity towards the determination of ATN in presence of organic and inorganic interfering species. The analytical performance of the PR-PGE has been studied successfully by determining ATN present in the pharmaceutical sample. [ABSTRACT FROM AUTHOR]

Since the discovery of carbon nanotubes, carbon nanotubes have quickly become a research hotspot for scholars worldwide due to their unique special properties such as mechanical, electronic, and chemical properties. It can be considered that the graphite sheet is folded into a carbon cylinder for application, and the carbon nanotubes can be divided into multi-walled carbon nanotubes. This article aims to study the electrochemical sensor for the detection of cyanide in food by nano-silver modified carbon nanotube electrode. In this article, the single-variable method and mathematical statistics are used to compare the electrochemical behavior of carbon nanotube ceramic electrodes with traditional carbon ceramic composite electrodes (CCE). At the same time, the different electrochemical responses of some biologically active molecules on the two electrodes were detected. The data were studied by mathematical analysis and the data were fitted by big data. Experimental data shows that NCE has a greater current response to these biomolecules at the same geometric area, and also changes the redox potential. It shows the advantages of NCE electrodes as sensors. NCE has a catalytic effect on the oxidation and reduction of H202 and NADH. Under the same experimental conditions, the contents of two substances H1O2 and NADH were detected using NCE and CCE, respectively. The experimental data show that the detection limit, sensitivity, and linear range of the electrochemical sensor for the detection of cyanide in food by the nano-silver modified carbon nanotube electrode have significantly improved compared with CCE, and the economic benefit has increased by about 16%. The degree of savings is increased by about 50%, which further proves that NCE has better electrochemical activity than CCE and is more suitable for the application of electrical analysis. [ABSTRACT FROM AUTHOR]

A Mo-doping LiFe1-xMoxPO4/C cathode material was synthesized via carbothermal reduction route, and the effect of the content of Mo on the structure and electrochemical performance of LiFePO4/C was studied. XRD results revealed doping of Mo did not change the olivine structure of LiFePO4/C, but also formed the Li+ vacancies, which contribute to increase the diffusion rate of Li+. The experimental results further demonstrated that among the Mo-doping samples, the LiFe0.98Mo0.02PO4/C exhibited the best cycle performance and rate performance. After 100 cycles at 0.1 C, its discharge specific capacity reached 143.2 mAh·g−1, which was about 10 mAh·g−1 higher than that of pure phase LiFePO4/C. The capacity retention rate was 98%. When cycling at a rate of up to 5 C, the discharge specific capacity of LiFe0.98Mo0.02PO4/C can still be maintained above 90 mAh·g−1, indicating that Mo doping was an effective method to improve LiFePO4/C electrochemical performance. [ABSTRACT FROM AUTHOR]

Common textile fabrication techniques have been utilised as scalable and cost-effective production methods for fabricating flexible 3 D textile electrode platforms. These textile structures may be readily integrated with electroactive electrodes that can potentially carry out electrochemical detection in wearable devices. Here we demonstrate that conductive fibre or yarn-based electrodes can be readily incorporated into knitted and braided textile structures for electrochemical detection. Due to the poor nature of these commodity-based conducting yarns and fibres surface modification utilising electrodeposition of conducting polypyrrole and or gold nanoparticles was demonstrated to enhance the device performance. [ABSTRACT FROM AUTHOR]

Here, hierarchically N-doped porous carbon (HPNC) with very high surface area was prepared by a facile one-pot pyrolysis of ethylenediaminetetraacetic acid tripotassium salt dihydrate used as the carbon/nitrogen source and pore activating agent. The NiCo2O4 nanosheets were vertically grown onto the surface of HPNC (V-NiCo2O4/HPNC) via a urea homogeneous precipitation method by a microwave heating. Whereas the parallelly orientated NiCo2O4/HPNC (P-NiCo2O4/HPNC) was fabricated by a usual water-bath heating. The loading content of V-NiCo2O4/HPNC was higher than that of the P-NiCo2O4/HPNC, thus resulting in the larger specific capacitance. V-NiCo2O4/HPNC exhibited the high specific capacity (434.8 F g-1 at 1.0 A g-1), good rate performance, cycle stability (capacitance retention of 103% at 5 A g-1 after 1000 cycles) and lower resistance, owing to the synergistic advantages of HPNC and vertically orientated NiCo2O4 nanosheets, which provided high electrical conductivity, and effective electrolyte ions and electrons transport path. [ABSTRACT FROM AUTHOR]

One of the bottlenecks often encountered in electro-Fenton technology is its low ability to produce hydrogen peroxide (H2O2). Thus, the hunt of suitable electrodes and reactor are a must to be tackled in order to improve the efficiency of the system. In this study, three-dimensional nickel foam was selected as cathode for in situ generating H2O2 efficiently and graphite was the control group in an enhanced oxygen mass transfer reactor. The micro-structure and electrochemical performance of electrodes were tested by scanning electron microscopy (SEM), X-ray diffraction (XRD), cyclic voltammetry (CV), electro-chemical impedance spectroscopy (EIS) and Tafel polarization techniques, respectively. The concentration of H2O2 produced by nickel foam cathode was 780.63 μmol/L and the removal efficiency of rhodamine B (RhB) was reached to 92.5% in 60 min. SEM and Tafel results showed that both nickel foam and graphite electrodes were porous structure cathodes. Moreover, CV and EIS experimental results indicated nickel foam electrode was controlled by charge transfer process while had a better transfer than graphite electrode. Electron spin resonance (ESR) spectra results demonstrated that the main oxidant species involved was ·OH, accounting for RhB degradation in electro-Fenton progress. Therefore, in terms of pollutant degradation in the electro-Fenton process, nickel foam electrode together with novel reactor was a promising technique. [ABSTRACT FROM AUTHOR]

Assembly of NiCo double hydroxide@NiC2O4 porous microspheres on Ni foam was fabricated by the direct anodisation of nickel foam (NF) and the subsequent electrodeposition of NiCo double hydroxide (NiCo-DH). The obtained Ni foam-supported NiCo-DH@NiC2O4 (NiCo-DH@NiC2O4/NF) was used as the binder-free electrode for electrochemical capacitor (EC). The combination of NiC2O4 and NiCo-DH increases the amount of active sites for redox reactions while the hierarchical porous morphology significantly enhances the diffusion of electrolyte. With Ni foam as 3D conductive substrate and current collector, the electronic conductivity of the electrode material was significantly improved and the diffusion of the electrolyte on the electrode surface was effectively enhanced. NiCo-DH@NiC2O4/NF demonstrates a high areal capacity, a good cycling stability and a good rate capability. In addition, a hybrid supercapacitor (HSC) assembled with NiCo-DH@NiC2O4/NF as the positive electrode and activated carbon (AC) as the negative electrode exhibited good performance with high energy density and power density. [ABSTRACT FROM AUTHOR]

LixNil/3Co1/3Mnl/3O2 powders were synthesized using a starch assisted combustion method, which reduced the heat-treatment time and decreased the particle size of the cathode materials. Particle size of the products gradually decreased with the increase of improver but the charging/discharging performance degraded by adding surplus improver. The results showed that performance of the sample was the best, when the amount of starch added was 650 g/L, of which the initial discharge capacity reached 156 mAh/g and the capacity remained 81.6% after 30 cycles. The starch added diminished the grain diameter but caused the phenomenon of burning and agglomeration when excessive used. [ABSTRACT FROM AUTHOR]

In this work, a high-performance electrode material has been fabricated by the incorporation of carbon nanotubes (CNTs) and polyaniline (PANI) on a carbon foams (CF) to improve its electrochemical performance. The microstructure and performance of as-prepared material was characterized in detail. Results showed that the resultant material exhibited a high gravimetric capacitance up to 467.1 F g−1, higher energy density of 104. 2 Wh kg−1 and power density of 3000 W kg−1 at a current density 3 A g−1 when the electrochemical doping time of PANI equals to 20 min. Furthermore, it appeared a good cycling stability with capacitance retention of 94.5% after 10000 cycles. The enhanced electrochemical performance can be attributed to the unique carbon nanostructure and synergistic effects of active materials CNTs and PANI. It indicates that this novel CF/CNTs/PANI-20 composite is a promising candidate for electrochemical capacitors. [ABSTRACT FROM AUTHOR]

A newly developed electrochemical sensor for chlorothalonil based on nylon 6,6 film deposited onto screen printed electrode (SPE) with electrochemical modulation of pH at the electrode/solution interface was studied for the first time. Differential pulse cathodic stripping voltammetry (DPCSV) was used to carry out the electrochemical and analytical studies. Experimental parameters such as accumulation potential, initial potential, accumulation time and pH of Britton-Robinson buffer have been optimized. Chlorothalonil gave optimum analytical signal in a medium of 0.04 M Britton-Robinson buffer at pH 6.0. A well-defined reduction peak was observed, at Ep= −0.851 and −0.938 V vs. Ag/AgCl (3.0 M KCl) for both bare SPE and modified SPE, respectively. The peak currents of modified SPE were significantly increased as compared to bare SPE. At the modified SPE, a linear relationship between the peak current and chlorothalonil concentration was obtained in the range from 0.1 to 2.8 × 10−6 M with a detection limit of 1.53 × 10−8 M (S/N= 3). The practical applicability of the newly developed method has been demonstrated on analyses of real water samples. The newly developed sensor shows good reproducibility with RSD of 3.92%. The nylon 6,6 modified SPE showed itself as promising sensor with good selectivity for chlorothalonil determination. [ABSTRACT FROM AUTHOR]

Application of a low-intensity electric field is known to influence oxidation-reduction (redox) potential in a saturated matrix. In this study, such redox manipulation was attempted in at a site with contaminated aquifer. At the experiment field site, electrodes connected to a direct current (DC) source provided an electric field with an intensity of 1.82 V m−1. Redox potentials at locations 3.0 m and 7.9 m from the cathode decreased by 111 mV and 33 mV within a few hours, respectively, indicating that reducing conditions in the aquifer may be established within the electric field. Overall, it is possible to manipulate in situ redox potential in saturated subsurface matrices by applying low-intensity electric fields. [ABSTRACT FROM AUTHOR]

In this article, the utility of a boron-doped diamond electrode for the determination of the fungicide oxycarboxin is demonstrated. For the first time, the square-wave voltammetry was employed in a quantitative determination of oxycarboxin on the boron-doped diamond electrode. It was found that oxycarboxin displays a well-expressed oxidation peak at a potential of ca. +1.5 V vs. Ag/AgCl in Britton–Robinson buffer with the maximum response in pH 4.0. As observed in cyclic voltammetry, oxycarboxin undergoes diffusion-controlled irreversible electrochemical oxidation. At optimised square-wave voltammetry parameters, the current response of oxycarboxin was linearly proportional to its concentration in the wide linear dynamic range of 8.0–100.0 μmol L−1(2.1–26.7 mg L−1). The developed electroanalytical method yielded a relatively low limit of detection of 1.6 μmol L−1(0.4 mg L−1), associated with high repeatability of the peak current expressed as relative standard deviation in the range of 1.1–2.9% for each concentration of oxycarboxin solution. This simple and sensitive method was proved to be suitable for an analysis of spiked river water samples with satisfactory results (relative standard deviation of 1.4%, recovery of 100.2%). The impact of possible interferences was tested and evaluated, and obtained results proved good selectivity of the proposed method. In addition, the influence of oxycarboxin on the corrosion properties of AISI 316 L stainless steel used as a construction material in farming was tested using potentiodynamic method, and a corrosive damage was characterised by means of scanning electron microscopy. [ABSTRACT FROM PUBLISHER]

This work describes the use of organosmectite modified electrode to evaluate the electrochemical behaviour and to develop an electroanalytical procedure for the determination of methyl orange (MO) dye in natural water. Organosmectites were prepared by intercalation of hexadecyltrimethylammonium cations at various ratios into the interlayer of smectite. The synthesised organosmectites were characterised by various physicochemical techniques such as Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy and transmission electron microscopy. An amperometric sensor based on organosmectite as electrode modifier for MO sensing purposes was then evaluated by means of clay-film modified electrode using square wave voltammetry (SWV). The electrochemical procedure for MO analysis by stripping voltammetry involves two successive steps: accumulation of MO at open circuit conditions followed by a voltammetric detection in a same medium by the SWV technique. The peak current obtained (after 5 min preconcentration of 15 µmol L−1 MO solution) on a glassy carbon electrode coated by a thin film of the modified clay was more than 2.5 times higher than that exhibited by the same substrate covered by a film of the pristine clay. Under optimised conditions, a linear calibration curve for MO was obtained in the concentration range from 0.1 to 1.6 µmol L−1, leading to a detection limit of 4 × 10−8 mol L−1(signal-to-noise ratio equal to 3). The interfering effect of various inorganic and organic ions likely to influence the stripping determination of the MO was also examined. To further validate application of this sensor, the proposed method was successfully used to the determination of MO in natural water with satisfactory results. [ABSTRACT FROM PUBLISHER]

Multi-walled carbon nanotubes (MWCNTs) were grown on cathode deposit by arc discharge plasma under H2, Ar, and air ambient environment. The influence of ambient gas pressure on the structure and physical properties of carbon nanotube were compared. Herein, we highlight the influence of ambient environment and pressure to grow high quality carbon nanotubes. Field emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and X-ray diffraction were used for structural characterization and yield determination. The result revealed that background gas and pressure were crucial factor for growing highly crystalline and highly graphitic with ID/IGratio 0.237 obtained for MWCNTs' synthesized in H2environment with extreme low defects. [ABSTRACT FROM AUTHOR]

Electrochemical machining (ECM) plays an important role in blisk manufacturing. There are two steps in blisk ECM: machining of channels and precise shaping of blade profiles. In channel machining, channels are machined in the workpiece with allowance left to the following process. Therefore, the main aim of channel machining with ECM is to improve the allowance distribution. With this aim, a new ECM method for blisk channels, spiral feeding ECM, is developed in which the cathode feeds from blade tip to hub along with rotation motion around its axis. Through this combined motion, twisted channels are produced in the workpiece. The relationship between feed position and rotation angle is presented in the form of a mathematical model. Experiments with a feed rate of 1 mm/min confirm that spiral feeding ECM is feasible and efficient. Compared with radial ECM, the allowance differences in blank back and blank basin decrease by 32.7% and 33.6%, respectively. The surface roughnesses Ra in blank back, blank basin, and hub are 0.358, 0.308, and 0.102 µm, respectively. Thus, the allowance distribution is improved to be more uniform considerably and the surface quality is relatively high. [ABSTRACT FROM AUTHOR]

A poly(Alizarin Red S)-conducting polymer was prepared on glassy carbon electrodes by multiple scan cyclic voltammetry using 0.1 M Alizarin Red S in pH 7 phosphate buffer. The poly(Alizarin Red S)-modified electrode was used for the direct determination of 2,3-dimethoxystrychnidin-10-one (brucine). The prepared poly(Alizarin Red S) electrodes were characterized by impedance spectroscopy and cyclic voltammetry. The influence of the supporting electrolyte, pH, and scan rate on the brucine current was characterized. The second cycle and the current signal value were selected to be optimum for quantitaive measurements. An irreversible oxidative peak and two pairs of well-defined peaks were obtained at the poly(Alizarin Red S)–glassy carbon electrode. The current from the second scan increased linearly with the concentration of brucine from 30 to 1,000 nM. The limit of detection for brucine was 5.0 × 10−9 M. The developed method was successfully used for the determination of brucine in human urine. [ABSTRACT FROM AUTHOR]

A mesoporous composite of single-walled carbon nanotube-doped ionic liquid/sol-gel titania/Nafion has been used for the fabrication of a highly sensitive electrochemical sensor for bisphenol A. Four ionic liquids with varying hydrophobicity, 1-butyl-3-methylimidazolium, 1-ethyl-3-methylimidazolium, 1,3-dimethoxy-2-methylimidazolium, and 1-benzyl-3-methylimidazolium hexafluorophosphates, were incorporated into the composite films. Although the composite- modified electrode with 1-butyl-3-methylimidazolium hexafluorophosphate exhibited the largest voltammetric response, the incorporation of ionic liquids, regardless of the type, into the composite-modified electrodes increased the electron transfer ability of the composite due to the high conductivity of ionic liquids and accumulated bisphenol A on the electrode surface due to p-p interactions between aromatic rings of bisphenol A and imidazole groups of the ionic liquids. Therefore, the combination of ionic liquid and electrocatalytically active single-walled carbon nanotube in the composite film provided excellent analytical performance compared to other electrochemical sensors for bisphenol A. Under the optimized conditions, the electrochemical sensor provided a linear response to bisphenol A from 1.0x10-9 to 1.0x10-5 M with a detection limit of 5.0x10-10 M. The sensor was selective to the analyte and also exhibited good reproducibility, with a relative standard deviation of 3.5%. [ABSTRACT FROM AUTHOR]

An improvement of the sludge electrodewatering process is proposed: anode flushing by filtrate recirculation. According to this technique, the mixture of filtrates obtained at cathode and anode sides is used for continuous flushing of the anode chamber of the filter press during electrodewatering. Anode flushing aims to eliminate essential problems of electrodewatering: ohmic heating, rise of electric energy consumption, electrode corrosion, and filtrate contamination. This is attained by better control of the filtrate pH, the filter cake temperature, and the dryness at the anode side, where the physicochemical conditions are most aggressive. The efficiency of the proposed technique is evaluated at lab scale on drilling sludge electrodewatering with and without anode flushing. In experiments without anode flushing, increasing electric current density caused strong increase of anode temperature, desiccation of the filter cake at the anode side, rise of voltage, and significant alkaline contamination of filtrate. The application of anode flushing allowed controlling the electric field strength and temperature. Thus, the dewatering of the sludge has been extended at high electric field without damaging the filter equipment by drastic heating. Furthermore, it reduced filtrate contamination by neutralization of the electrolysis products. [ABSTRACT FROM PUBLISHER]

Electrochemical oxidation of 1,3-di(para-tolyl)-5-para-toluidinomethyl-1,3,5-diazaphosphorinane on various soluble metallic anodes (Al, Cu, Ni) was investigated. Influence on the electrochemical process of such factors as the nature of the metal, anode potential of electrolysis and amount of the passed electricity was established. [ABSTRACT FROM AUTHOR]

Carbon nano-onions, multiwall carbon nanotubes and Y-branched nanotubes are synthesised in a simple production apparatus. A pulsed plasma is generated by discharging a high voltage needle pulse between two graphite electrodes. A strong electric field is presented along anode and cathode electrodes. The pulse width is 0.3 μs. Acetone vapour, as a precursor, is introduced to the plasma through a graphite nozzle in the cathode assembly. A magnetic field, perpendicular to the plasma path, is provided. The possibility of carbon nanotube production through a short-pulsed arc discharge technique is investigated in this article. The results show that adding an electric field between electrodes prevents carbon ions’ dispersion, facilitates charge transferring between ions and electrodes, orients the growth of carbon nanotubes along the applied electric field and finally makes it possible to produce functionalised carbon nanoparticles such as Y-branch nanotubes and nanoknees. In this work, the growth mechanism of carbon nanotubes in a needle-pulsed arc-discharge reactor is discussed. And a possible explanation is provided for the synthesis of Y-branch carbon nanotubes. The products are examined by using scanning probe microscopy technique. [ABSTRACT FROM AUTHOR]

Phase pure, monoclinic and nanostructured LiFePO4/C composites have been synthesised via rheological phase method at different temperatures and characterised by X-ray diffraction, thermogravimetry and SEM. The electrochemical measurements showed that calcination temperatures have great influence on the electrochemical performances of LiFePO4/C composite as the cathode materials for Li ion batteries. When the calcination temperature was 650°C, the LiFePO4/C composite showed high capacities and good cyclabilities with the discharge capacities still reaching 151.3 mA h g− 1 after 50 charge-discharge cycles. It shows that the properly chosen temperature was significant for LiFePO4/C composite with good electrochemical performance for Li ions batteries application. [ABSTRACT FROM AUTHOR]