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An effective way of monitoring the biomarker is with electrochemical sensor studies. In this work, it was formed using electrochemical deposition of high conductivity gold nanoparticles (AuNPs) and an amine-functional reduced graphene oxide (NH2-RGO) nanocomposite. This technique not only reduced HAuCl4 and graphene oxide in situ but also improved the electrocatalytic performance. XRD, SEM, and FTIR analytical methods confirmed the size and structure of the AuNPs/NH2-RGO nanoparticle. As a result of XRD analysis, AuNPs/NH2-RGO crystal structure was formed. In addition, antibodies (Ab) were immobilized on the modified electrode surface using a self-assembled monolayer. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods were used to evaluate the interaction of Ab with antigen. SHBG detection had a dynamic linear range of 0.6–12 nmol/L and a limit of detection (LOD) of 0.0043 µM in enhanced sensor applications. The AuNPs/NH2-RGO based sensor has the potential to be a valuable tool in clinical diagnostic applications in the future. [ABSTRACT FROM AUTHOR]

Controlling water and food contamination by pathogenic organisms requires quick, simple, and low-cost methods. Using the affinity between mannose and type I fimbriae in the cell wall of Escherichia coli (E. coli) bacteria as evaluation elements compared to the conventional plate counting technique enables a reliable sensing platform for the detection of bacteria. In this study, a simple new sensor was developed based on electrochemical impedance spectroscopy (EIS) for rapid and sensitive detection of E. coli. The biorecogniton layer of the sensor was formed by covalent attachment of p-carboxyphenylamino mannose (PCAM) to gold nanoparticles (AuNPs) electrodeposited on the surface of a glassy carbon electrode (GCE). The resultant structure of PCAM was characterized and confirmed using a Fourier Transform Infrared Spectrometer (FTIR). The developed biosensor demonstrated a linear response with a logarithm of bacterial concentration (R2 = 0.998) in the range of 1.3 × 10 1~1.3 × 106 CFU·mL−1 with the limit of detection of 2 CFU·mL−1 within 60 min. The sensor did not generate any significant signals with two non-target strains, demonstrating the high selectivity of the developed biorecognition chemistry. The selectivity of the sensor and its applicability to analysis of the real samples were investigated in tap water and low-fat milk samples. Overall, the developed sensor showed to be promising for the detection of E. coli pathogens in water and low-fat milk due to its high sensitivity, short detection time, low cost, high specificity, and user-friendliness. [ABSTRACT FROM AUTHOR]

Carbon materials have been used in the field of supercapacitors. However, the lower electrochemical performance limits its wide application. Polyaniline (PANI) possesses excellent controllable electrochemistry. Therefore, a composite material composed of polyaniline and carbon materials will significantly improve the electrochemical performance of carbon materials alone. In this article, the carbon/PANI composite mesh electrode materials were prepared by electrochemical polymerization. The carbon mesh with highly wrinkled nanoscale microstructure is an excellent substrate material of polyaniline. The agglomerate morphology of polyaniline on the carbon mesh can be efficiently controlled by the number of CV cycles. The polyaniline agglomerated coating of the carbon/PANI-45 composite mesh exhibits a multi-scale pore microstructure: abundant macropores, mesopores and micropores. This unique electrochemically deposited porous structure can significantly improve electrochemical performance of the carbon/PANI-45 mesh electrode material due to efficient ion transport channels and electron transport path. The area-specific capacitance of the carbon/PANI-45 based interdigital supercapacitors is up to 246.7 mF/cm2 at the current density of 20 μA/cm2. The area-specific capacitance retention rate is about 93.1% when the current density increases to 200 μA/cm2. The carbon/PANI composite mesh electrode materials were prepared by electrochemical polymerization, exhibiting good electrochemical performance. [ABSTRACT FROM AUTHOR]

In this report, effects of Cr doping on structural, morphological, mechanical and magnetic properties of Ni–Co–Cr alloy thin films have been prepared by electrodeposition method with different concentration. The influence of Cr substitution on the formation of phases, structure, morphology, hardness and magnetic properties of the electrodeposited films are studied by X-ray diffraction (XRD), scanning electron microscope (SEM), Vickers hardness tester (VHT) and vibrating sample magnetometer (VSM). The SEM micrographs of the electrodeposited films with different concentration of Cr have no micro-cracks with uniform surface morphology. The predominant peaks in XRD spectra of Ni–Co–Cr alloy thin films reveal nanostructure. The VHT result clearly showed that thin films coated with high concentration of Cr have highest hardness value. The magnetic properties such as saturation magnetization and coercivity influenced more by varying the concentration of Cr. [ABSTRACT FROM AUTHOR]

The present paper describes the use of electrodeposited Co(OH)2 on transparent conducting fluorine-doped tin oxide electrode (FTO) as functional material for ascorbic acid electrooxidation in different electrolyte solutions. The structure, composition, and morphology of film were investigated through Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectrum (EDS), and scanning electron microscope (SEM). The electrochemical characterization in different electrolyte solutions was carried out by cyclic voltammetry (CV) and chronoamperometry. The voltammetric profile showed the presence of two possible reactions involving almost reversible redox processes during sweeping potential in KOH solution and a single redox process in KCl solution. The Co(OH)2 film presented electrocatalytic activity in ascorbic acid electrooxidation, being the sensitivity values found were 182.3 mA L mol−1 cm−2 and 119.4 mA L mol−1 cm−2 in KOH and KCl solutions, respectively. The results showed that the electrolytic solution strongly influenced the sensitivity of the FTO/Co(OH)2 film in ascorbic acid electrooxidation reaction. Kinetic studies showed that the electrode process was controlled by mass diffusion. In addition, chronoamperometric technique was carried out to verify the stability of the electrode. The obtained results reveal a good stability of electrode in the KCl solution; once in current density terms, the results are quite similar. [ABSTRACT FROM AUTHOR]

Poly(3-methylthiophene)/reduced graphene oxide (P3MT/RGO) modified glassy carbon electrode (GCE) was fabricated via a facile procedure. P3MT was directly electrodeposited on the RGO coated electrode and employed for the electrochemical detection of paracetamol (PCT). The morphology of composite was characterized by scanning electron microscopy (SEM). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to investigate the electrochemical behaviors of PCT on P3MT/RGO/GCE. Experimental parameters, such as the scan rates, polymerization laps and the pH of buffer solution were optimized. Under the optimal conditions, the anodic peak current in DPVs varies linearly with the concentration of PCT, and the limit of detection was 0.025 μ M. Moreover, the proposed P3MT/RGO/GCE also exhibited superior stability and reproducibility. The poly (3-methylthiophene)/reduced graphene oxide (P3MT/RGO) material was firstly proposed for the fast, sensitive electrochemical determination of paracetamol (PCT). The RGO can efficiently provide abundant reaction sites and promote the electron transfer, while the P3MT was electrodeposited on the surface of RGO/GCE. The redox current response increased further and the reversibility of the redox reaction was improved. The developed sensor showed excellent stability, high selectivity, low detection limit and good applicability in real samples. [ABSTRACT FROM AUTHOR]

An investigation about influence of deposition current density on electrodeposited magnetic film is reported in this paper. Ferromagnetic NiFe thin films were electrodeposited on copper wires of 100 μm diameter for various electrdepostion current densities ranging from 10 to 60 mA/cm maintaining equal thickness in all films. The composition of deposited film varied with deposition current density and in particular, a composition of NiFe was achieved for a current density of 20 mA/cm. The surface microstructure of the film deposited at the current density of 20 mA/cm was found to have excellent smoothness. The coercivity of the film was lowest and highest value of magnetoimpedance was measured for this film. The influence of current density on film composition and hence magnetic properties was attributed to the change of deposition mechanism. [ABSTRACT FROM AUTHOR]

Three kinds of Fe-based thin films, Fe–20%Ni–80%, Fe–60%Co–40%, and Fe–10%Ni–60%Co–30% (at %), were prepared on silicon (1 1 1) substrates by direct current electrodeposition with the optimized plating conditions. Films were annealed at various temperatures from 200 to 400 °C, varying time from 2 to 4 h. The microstructure, surface morphology, and chemical composition have been investigated by X-ray diffraction, scanning electron microscopy, energy dispersive spectrometer with electron probe micro-analysis, respectively. The magnetic properties were measured by the superconducting quantum interference device magnetometer. Effect of heat treatment on films is then discussed. [ABSTRACT FROM AUTHOR]

The objective of this study was to clarify the effect of an electrodeposited Ca film on hydrogen entry behavior into API-X65 by measuring the hydrogen content and by an electrochemical hydrogen permeation technique in Ca(OH)2 and NaOH solutions under constant current cathodic hydrogen charging. As a result, the hydrogen content in the steel cathodically charged in the Ca(OH)2 solution was larger than that in the NaOH solution, which was attributed to the formation of the Ca film. The hydrogen permeation efficiency on the area where the electrodeposited Ca film did not exist (reaction part) was measured by the electrochemical hydrogen permeation technique. It was clarified that with 0 to 40% of electrodeposited Ca film coverage, the hydrogen permeation efficiency increased and hydrogen entry was enhanced at the reaction part. It was clarified that hydrogen permeation efficiency decreased and hydrogen entry was inhibited at the reaction part when the electrodeposited Ca film coverage was more than 40%. [ABSTRACT FROM AUTHOR]

The late stage abnormal grain growth in the electrodeposited nickel is characterised by the occurrence of very large grains with unusual planar interfaces in a uniformly growing matrix. In our study, the nickel specimens deposited in electrolytic bath with different saccharin concentrations presented different abnormal grain growth tendencies, while the common feature is the cubic shape of the abnormal grain. The planar interfaces between the large grain and the matrix were proved to incline on the {1 0 0} plane, and the cubic shape of the abnormal grain in three dimensions was reconstructed by analysing the orientation relationship of the grains. [ABSTRACT FROM AUTHOR]

A systematic variation of film composition was done during electrodeposition of NiFe thin films onto 100 μm diameter copper wire. Current density of deposition was maintained at 20 mA/cm to ensure constant film thickness. Pure Ni film as well as Fe rich NiFe film were not magnetically soft enough and showed poor magnetoimpedance effect. As Fe concentration was systematically varied, softest magnetic properties and magnetoimpedance value were found for the film composition NiFe. Soft magnetic properties induced and magnetoimpedance effect observed at this composition was attributed to the lowering of magnetoelastic anisotropy as well as magnetocrystalline anisotropy. [ABSTRACT FROM AUTHOR]

The Young's moduli of electrodeposited Ni with different dimensions were measured carefully in this paper. The dimensions of tensile specimens were 200, 35, or 5 μm thick and 2400, 200 or 50 μm wide. These specimens were measured with three different approaches. The measured Young's moduli of Ni decrease from 122.1 ± 4.3 to 92 ± 5.2 GPa when the thickness changes from 200 to 5 μm and width changes from 2400 to 50 μm. [ABSTRACT FROM AUTHOR]

The anneal response and high-temperature ductility for four commercial- grade 35-µm rolled (R: GR5) and electrodeposited (ED: GR1, GR3, and TCAM) copper foils, used for rigid and flexible printed circuits, are investigated. Using tensile and microhardness monitors, the anneal response is examined to 900°C for up to 300 min, and the high-temperature ductility is characterized to a 200°C test temperature. For comparison, the ED "control" foils, using deposition parameters identical to those for the commercial foils but without the additives usually introduced in the electrolyte, are also examined. The ED control foils thermally soften readily; the temperature range of softening decreases with the electrodeposition overvoltage (ζ). For the commercial grade foils, the proprietary additives help tailor thermal softening but cause severe disruption of anneal kinetics (TCAM) and embrittlement at (TCAM) and above (GR1, GR3) 23°C. [ABSTRACT FROM AUTHOR]

Diffusion brazing has gained much popularity as a technique capable of joining dissimilar lightweight metal alloys and has the potential for a wide range of applications in aerospace and transportation industries, where microstructural changes that will determine the mechanical and chemical properties of the final joint must be controlled. This study explores the effect of Al2O3 nanoparticles on the mechanical and microstructural properties of diffusion brazed magnesium (AZ31) and aluminium (Al-1100) joints. The results showed that the addition of Al2O3 nanoparticle to the electrodeposited Cu coating increased the volume of eutectic liquid formed at the interface which caused a change to the bonding mechanism and accelerated the bonding process. When the Cu/Al2O3 nanocomposite coatings were used as the interlayer, a maximum bond strength of 46 MPa was achieved after 2 min bonding time while samples bonded using pure-Cu interlayers achieved maximum strength after 10 min bonding time. Chemical analysis of the bond region confirmed that when short bonding times are used, the intermetallic compounds formed at the interface are limited to the compounds consumed in the eutectic reaction. [ABSTRACT FROM AUTHOR]

In this study, alpha nickel sulfide (α-NiS) nanosphere films have been successfully synthesized by electroplating the nickel nanosheet film on the indium tin oxide (ITO) glass substrate and sulfuring nickel-coated ITO glass substrate. First, we electrodeposited the nickel nanosheet films on the ITO glass substrates which were cut into a 0.5 × 1 cm2 size. Second, the nanosheet nickel films were annealed in vacuum-sealed glass ampoules with sulfur sheets at different annealing temperatures (300, 400, and 500 °C) for 4 h in vacuum-sealed glass ampoules. The α-NiS films were investigated by using X-ray diffraction (XRD), variable vacuum scanning electron microscopy (VVSEM), field emission scanning electron microscopy/energy dispersive spectrometer (FE-SEM/EDS), cyclic voltammogram (CV), electrochemical impedance spectroscopy (EIS), ultraviolet/visible/near-infrared (UV/Visible/NIR) spectra, and photoluminescence (PL) spectra. Many nanospheres were observed on the surface of the α-NiS films at the annealing temperature 400 °C for 4 h. We also used the high-resolution transmission electron microscopy (HR-TEM) for the analysis of the α-NiS nanospheres. We demonstrated that our α-NiS nanosphere film had a linear current response to different glucose concentrations. Additionally, our α-NiS nanosphere films were preserved at room temperature for five and a half years and were still useful for detecting glucose at low concentration. [ABSTRACT FROM AUTHOR]