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As the world is moving towards technological advancement and industrial revolution, the need for eco-friendly and portable energy sources for various applications is and will going to increase. We are surrounded by so many gadgets to run our daily life smoothly. Li-ion battery stood out as the most reliable and suitable device for storing energy so far which have applications from small scale to bigger applications like electric vehicles. Highest theoretical capacity of 3860 mAhg−1 for Li metal anodes, lightweight, high energy density and many other parameters makes it attractive choice for the applications whereas it shows the lowest electrochemical potential of −3.04V versus standard hydrogen electrode (SHE). Researchers are trying the alternate materials for cathode and anode where different structural cathode materials are being tested and various anode chemistries have been tried. Silicon anode has the potential to replace the regular graphite anode-material as it has 10 times the specific capacity as compare to graphite. This paper reviews the anode materials which are currently under research to enhance the characteristics of Li-ion battery in comparison with the currently commercialized graphite anode (372 mAhg−1) that how structural and morphological modification can change the properties like cycle life, shelf life, specific capacity, charge rate and stability of the materials. [ABSTRACT FROM AUTHOR]

The production of organic molecules from CO2 is extremely desirable from both an energy and environmental standpoint. High-performance catalysts are necessary to accomplish such a desirable outcome. In this study, CO2 reducion reaction (CO2RR) pathways to formic acid, methanol, and CH4 are investigated over a two-dimensional transition metal diboride TiB2 using DFT calculations combined with the hydrogen electrode model. Analysis of the adsorption configurations and electronic structures demonstrated that CO2 could be chemically adsorbed on the Tis side of TiB2 with an adsorption energy of −2.47 eV. Further, our study revealed that the TiB2 enabled CO2RR to proceed through multiple electron paths to produce HCOOH and CH3OH with limiting potentials of 1.11 eV and 1.20 eV, respectively. Additionally, CO2RR via the two-electron pathway would result in HCOOH along the COOH pathway rather than CO with a comparatively low ΔG of −0.42 eV. Our research might open up new avenues for the electrocatalytic CO2 reduction applications of 2D metal diborides. [ABSTRACT FROM AUTHOR]

Two samples of (Ag NPs-zeolite) nanocomposite thin film have been prepared by the easy hydrothermal method for 6 times and 8 times respectively, inside the hydrothermal autoclave at a temperature of 100°C. The two samples were used in a photoelectrochemical cell as a photocatalyst inside a cell consisting of three electrodes: the working electrode photoanode (AgNPs-zeolite), platinum as a cathode electrode, and Ag/AgCl as a reference electrode, to study the performance of AgNPs-zeolite under dark and (532,473 nm) laser light for water splitting. The results show the high performance of an eight-hour sample with high crystallinity compared with a six-hour sample as a reliable photocatalyst to generate hydrogen for renewable energy. [ABSTRACT FROM AUTHOR]

Aspartame is one of the artificial sweeteners, which if it consumed in excess of the prescribed limits will promote negative effects such as headaches, dry mouth, and seizures. In this report, an electrochemical sensor for detecting aspartame is investigated by using square wave voltammetry (SWV) technique in phosphate buffer solution (PBS). In this study, aspartame analysis utilized glassy carbon electrodes (GCE) as working electrodes, platinum as counter electrodes, and Ag/AgCl as reference electrodes. The linear range was in the concentration range of 30 - 100 µM with limit of detection of 3.66 µM. The results also show the satisfactory of reproducibility with RSD of 2.20 %. [ABSTRACT FROM AUTHOR]

This paper presents the synthesis of a series of Schiff bases derived from phenothiazine derivatives with fluorine benzaldehydes. The compounds were characterized physicochemically by NMR and IR spectroscopy, and their parameters were determined by appropriate methods. Their antimicrobial activity against various microorganisms were studied. One of the compounds showed weak activity against Bacillus subtilis and Salmonella abony. The rest were not active against the microorganisms used. The corrosion characteristics of the obtained compounds were studied using electrochemical techniques (cyclic voltammetry, polarization curves and impedance spectroscopy) in a three-electrode corrosion cell relative to (hydrogen reference electrode) RHE. The samples were applied to an experimental, ground graphite electrode using a spray technique with a thickness of about 50 µm. A detailed analysis of the internal resistance was carried out, including equivalent model schemes and experimental data. [ABSTRACT FROM AUTHOR]

World has come across various natural transformations and process which has its own pros and cons. Metals are widely used in the world for multiple reasons in which the materials are hard, lustrous, malleable used commonly in construction industry, technology development, medicinal products, space researches etc. A natural transformation process caused by essential phenomena like water, air and gaseous things which leads to an electro-chemical action called corrosion. The corrosion causes cautious destruction to the metals by attacking it through various chemical and electro-chemical processes. Corrosion of reinforcing steel and other embedded metals is the leading cause of deterioration in concrete. When steel corrodes, the resulting rust occupies a greater volume than the steel. This expansion creates tensile stresses in the concrete, which can eventually cause cracking, delamination, and spalling. This report aims to access and determine the range of corrosion in a reinforced structure by half-cell potentiometer with different reference electrode to get the accuracy between the them, impressed current technique is used for acceleration of corrosion. The experimental study includes the compressive strength, flexural strength and tensile strength tests are also conducted for the designed concrete sample in the grade of M20. [ABSTRACT FROM AUTHOR]

Hydrogenated diamond-like carbon (HDLC) thin film was synthesized using reactive gas plasma produced in a capacitively coupled plasma system onto silicon (100) wafer substrates. These thin films were extracted by boiling with cyclohexane under reflux in round bottom flux. The photophysical character of the extracted solution was studied by using a UV-Visible spectrometer. A reversible nature of the absorbance was observed in the extracted films solution with respect to over a temperature range from 20-80 0C. Cyclic voltametry experiment was run in the potential range -1.0-1.0 with scan rates (100 mVs-1) using redox couple [Fe(CN)6]4-/[Fe(CN)6]3- in an unperturbed 1mM ferricyanide solution in 0.1M H2SO4 solution. HDLC thin film substrate was used as the working electrode, a Silver wire was worked as a reference electrode and Pt wire as a counter electrode. It is seen that the potential difference between anode and cathode peaks is 0.449 V which referred that our HDLC's surface act as an irreversible electrode that is it can donate as well as accept an electron. [ABSTRACT FROM AUTHOR]

In the present work, the corrosion behavior of Zn67Mg33 and Zn62Mg29Y9 alloys (element concentration in at. %) has been investigated. The alloys were prepared by induction melting of pure elements in an argon atmosphere. The microstructure and phase constitution of the alloys were studied by scanning electron microscopy and X-ray diffraction, respectively. The cast materials were found to consist of several microstructure constituents. The Zn67Mg33 alloy was composed of Zn2Mg as the main component and a small amount of Zn2Mg+(Zn) eutectic. The Zn62Mg29Y9 alloy was composed of MgZn, Mg7Zn3, I-phase (Zn6Mg3Y) and H-phase ((Zn,Mg)5Y), respectively, in approximately equal amounts. The corrosion resistance of the as-cast alloys was studied at room temperature using the electrode polarization method. A three-electrode cell with a saturated Ag/AgCl reference electrode, a Pt counter electrode and a metallic working electrode was used for the measurement. The progress of the reaction was controlled by potentiostat. Corrosion potentials and corrosion currents were found by Tafel extrapolation of experimental polarization curves. The corrosion currents were subsequently used to estimate the corrosion rate. Three aqueous solutions of HCl (0.01 mol dm−3), NaOH (0.01 mol dm−3) and NaCl (0.6 mol dm−3) were chosen as corrosion media to study the effects of pH and chloride concentration on the corrosion rate. The highest corrosion rate of the alloys was found in the acidic HCl solution. The corrosion rate was found to decrease sharply with increasing pH of the electrolyte. The highest corrosion resistance of the alloys was found in the alkaline NaOH solution. For the investigated alloys, the corrosion mechanism is suggested and effects of both chemical compositions and microstructure are discussed. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) water splitting is among of the greatest assuring methods in producing hydrogen. One of the alternative semiconductor materials used as a photoanode for water-splitting applications is ZnO. However, this compound has several drawbacks that can be overcome by combining it with noble metal particles. In this study, ZnO nanorods (NRs) were synthesized using the hydrothermal method and then decorated with AuAg mesoflowers (MFs) synthesized by the wet chemical method. A linear sweep voltammogram (LSV) measurement under visible light and AM 1.5 G shows that the ZnO/AuAg MFs produced the highest photocurrent in the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) with the highest efficiency, of 0.034 % at a voltage of 0.874V vs reversible hydrogen electrode (RHE). The AuAg MFs may act as electron donors, injecting electrons into the ZnO conduction band to increase the photocurrent. [ABSTRACT FROM AUTHOR]

Thin films of tin selenide (SnSe) were synthesized by electrochemical process at a deposition potential of -0.6 V (Ag/AgCl reference electrode) at room temperature (27oC). X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were employed to characterize the thin films and morphology of the material and to indicate chemical composition respectively. Thermoelectric properties were measured with temperature variation. Figure of merit (ZT) has been calculated with varying temperature and ZT=1.31 has been obtained at 373 K. [ABSTRACT FROM AUTHOR]

Thermal runaway is occurs in batteries of almost all electrochemical systems. In the event of thermal runaway, the system containing the battery inevitably fails. The paper analyzed a number of experimental facts that prove that the generally accepted point of view on thermal runaway in nickel-cadmium batteries is incorrect. It is proved that thermal runaway is associated with the emergence of a powerful exothermic reaction, i.e. recombination reactions of atomic hydrogen accumulated in the electrodes. It is shown that in sealed nickel-cadmium batteries, thermal runaway occurs about ten times less intensively than in unpressurized batteries. [ABSTRACT FROM AUTHOR]

The effects of boric acid (H3BO3) concentration in the formation of electrodeposited Ni-TiAlN composite coating has been studied. The coatings were electrodeposited at fixed current density of about 1,5 mA for 15 minutes. The electrolyte solution consists 0.09 M NiCl2.6H2O, 0.63 M NiSO4.6H2O, 0.2 g/L Sodium Dodecyl Sulfate (SDS), 4 g/L AlN and 4 g/L TiN. The concentration of H3BO3 was varied into 30, 35 and 40 g/L. Three electrode cells were used in this study, silver (Ag) wire as reference electrode, Pt wire as counter electrode and tungsten carbide (WC) rod as working electrode. The surface morphology and composition of coatings were evaluated by using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS), respectively. The crystal structure and hardness of coating was identified by using X-Ray Diffraction (XRD) and hardness Vickers test, respectively. The results indicated that the increase in H3BO3 concentration modified the surface morphology and crystal structure of Ni-TiAlN composite coating and promote the improvement of its hardness. [ABSTRACT FROM AUTHOR]

pH is an important parameter in desulfurization facilities and the generation of boiler tube scales in thermal power plants. As an indicator of hydrogen ion concentration in aqueous solution, it is a major item in the management of pure water and wastewater quality treatment. The most important problem in pH is the difficulty of maufacturing pH electrode. The pH measurement does not follow other ion analysis in terms of sensitivity or measurement range. Therefore, the pH electrode needs to be more realistically considered than any other pH electrode. In this paper, we propose a method of manufacturing solid state electrolyte which can solve the difficulties of preventing the backflow in raw water quality management of thermal power plants and further identify the method of manufacturing pH combination electrode processed by injecting solid state electrolyte into the lower portion of inner electrolyte formed of reference electrode where even if pressure or surrounding environment changes and any external foreign debris flows through the junction, the flow of the outer electrolyte is blocked and prevents reference electrode from being hazardously contaminated by any outer source or environmental changes. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal anode has long been regarded as the "Holy Grail" in the field of battery, owing to the lowest redox potential (-3.045 V vs. standard hydrogen electrode) and ultra-high theoretical specific capacity (3860 mAh/g). However, its practical application is seriously hindered by Li dendrite growth, parasite reaction, infinite volume change, etc. Herein, to construct a stable surface for advanced electrochemical performance, a homogeneous ZrO2 film was sputtered on lithium metal anode. The symmetric cell of Li metal coating with 37 nm ZrO2 exhibits long life-span over 920 h at 0.5 mA/cm² for 1 h in carbonate electrolyte. The coating layer prevents the parasite reaction efficiently. Furthermore, the flat and dense ZrO2 coating layer regulates homogeneous deposition of Li metal so that the dendrite-free Li is achieved. [ABSTRACT FROM AUTHOR]

In order to understand the H" extraction mechanism and investigate the effect of the extraction voltage applied by the puller-electrode on the H- extraction in the Linac4 negative ion source, we are developing a 2D3V-PIC (two dimensions in the real space and three dimensions in the velocity space, Particle in Cell) model with volume produced H" ions. It is shown that how to take the magnetic filter field direction is important for the 2D modeling to take into account the important 3D effect of electron ExB drift. It is also shown that the meniscus formation is not symmetric due to the electron ExB drift in the extraction region and the divergence of the H" beam is asymmetric. In order to make more quantitative comparison of the extracted H- and electron currents with the experiments and 3D modeling, further improvements, especially the electron loss along the magnetic filter field line will be needed. [ABSTRACT FROM AUTHOR]

This study used a fast, simple, and low-cost method to fabricate arrayed flexible glucose biosensor, and the glucose biosensor was integrated with microfluidic framework for investigating sensing characteristics of glucose biosensor at the dynamic conditions. The indium gallium zinc oxide (IGZO) was adopted as sensing membrane and it was deposited on aluminum electrodes / polyethylene terephthalate (PET) substrate by the radio frequency sputtering system. Then, we utilized screen-printed technology to accomplish miniaturization of glucose biosensor. Finally, the glucose sensing membrane was composed of glucose oxidase (GOx) and nafion, which was dropped on IGZO sensing membrane to complete glucose biosensor. According to the experimental results, we found that optimal sensing characteristics of arrayed flexible IGZO glucose biosensor at the dynamic conditions were better than at the static conditions. The optimal average sensitivity and linearity of the arrayed flexible IGZO glucose biosensor were 7.255 mV/mM and 0.994 at 20 µL/min flow rate, respectively. [ABSTRACT FROM AUTHOR]

In this study, the radio frequency (R. F.) sputtering system and screen printing technology were used to fabricate the arrayed pH sensor. And the glucose oxidase (GOx) enzyme was immobilized on the arrayed pH sensor as the arrayed glucose biosensor. Furthermore, the computer numerical control (CNC) technique was used to fabricate the microfluidic mold. The differential reference electrode can provide a stable potential in different pH solutions, which was applied in arrayed pH sensor and arrayed glucose biosensor. The arrayed pH sensor and arrayed glucose biosensor were integrated to the poly-dimethylsiloxane (PDMS) microchannel as the microfluidic device for observing the characteristics of the arrayed pH sensor and arrayed glucose biosensor at dynamical conditions. At dynamical conditions with flow rate controlled at 20 ml/min, the average sensitivity and linearity of the arrayed pH sensor were 57.27 mV/pH and 0.986, respectively. And at the flow rate controlled at 5 ml/min, the average sensitivity and linearity of the arrayed glucose biosensor were 9.67 mV(100 mg/dL)-1 and 0.943, respectively. [ABSTRACT FROM AUTHOR]

The Reversible Hydrogen Electrode (RHE) was applied as a sensor for real time bacterial hydrogen production rate determination, since the RHE potential depends on the dissolved hydrogen concentration (at pH=const) determined by the H2 pressure according to the Henry's law. The rapid RHE response allows real time determination of the kinetic parameters of the photosynthetic bacterial hydrogen generation. The photosynthetic strain Rodobacter Capsulatus , genetically modified variety IR3 in RCV medium was employed for this purpose in 10 ml reactor at anaerobic conditions and pH=const. for optimization of the bacterial photosynthetic hydrogen generation conditions [ABSTRACT FROM AUTHOR]