Exploding Wire Technique Research Articles

Experimental analysis on the exploding wire process for nanopowder production: Influence of initial energy and exploding atmosphere

Metallic nanopowder is employed in several applications for its flexibility of use, thus its production is growing over the years. Exploding wire technique can produce a wide range of nanoparticles from electrically conducting samples, and it has a potential for high efficiency and productivity, due to the strongly localized power dissipation. On the other hand, the phenomena involved during the explosion are complex, and phenomenological relationships are usually considered for controlling the output product characteristics. In this study, we investigated the effect of the input energy and the medium in which the explosion takes place on the final dimensional distribution of the nanopowder. Utilizing a proper power supply and an exploding system developed on purpose, we applied up to 10 GA/m2 to copper wire samples immersed in air or water. We collected the products for morphological analysis, we carried out a shape and dimensional characterization based on a statistical analysis of the obtained particles, and we compared and discussed the results concerning the adopted initial conditions and the most recent literature data.

Modelling of the exploding wire technique, a novel approach utilized for the synthesis of nanomaterials

Abstract Of late, the exploding wire technique (EWT) is being popularly utilized for high yield synthesis of diverse nanomaterials. In this paper, we propose an equivalent electrical circuit-based model of this technique when the explosion of wire against a metallic plate takes place in the presence of aqueous medium. The wire transforms into plasma state immediately after explosion and formation of liquid-vapour mixed phase is imminent in this process. We elucidate the conversion of metallic wire into partially ionized plasma by a set of semi-empirical mathematical equations. We propose a mathematical electrical conductivity model for analysing complex behaviour of wire explosion in a liquid medium. The present work results are restricted to one-dimension but could be extended to two- and three-dimensional codes associated with the dynamics of z-pinch or x-pinch.

Dielectric study of pure CuO nanoparticles prepared through exploding wire technique

Dielectric study of pure CuO nanoparticles prepared through exploding wire technique

A Single Layer of Chromium Oxide Nanoparticles Films Coated with Carbon by Applying Exploding Wire Technique for Efficient Solar Selective Absorber

The efficiency of solar energy absorption in solar heaters is increased by the use of selective absorption coating that possesses high absorption of solar radiation in the UV-visible spectrum as well as low emission at the operating temperature in the infrared region. In this work, novel selective coatings were synthesized by improving the selectivity of chromium oxide (Cr2O3) nanoparticles by doping with carbon nanoparticles using the exploding wire technique for carbon rods by high current in suspended Cr2O3 particles. The structural properties and surface topography were studied by XRD and FE-SEM, which illustrate the carbon-coated Cr2O3 nanoparticles. The prepared nanoparticles were mixed with a support material, Polyvinyl pyrrolidone (PVP) as a matrix, for use as a selective coating for three metals, namely copper, aluminium and stainless steel (SST). Reflectivity measurements were performed within the UV-Visible spectrum to calculate the absorption of solar radiation using numerical integration. The reflectivity was also measured in the range from 2.5 to 25 μm to calculate the thermal emission of the solar heater within the proposed operating temperature of 373 K. The measurements showed good efficiency of using the produced material as a selective coating which was prepared in a simple way compared to conventional methods. The best sample with efficient absorptance (α) for solar spectrum and of lowest emittance (ε) in IR region was for Al substrate coated by Cr2O3:C:PVP of α =0.886 and ε= 0.260.

Stable exploding wire plasma at times larger than electrical current presence

Copper gas produced with the exploding wire technique at times much larger than the total current lifetime has been explored, and its excitation temperature estimated from spectrographic data. It has been found that excitation temperature is stable for microseconds after the electrical current finish to flow and dependent only on charging voltage for the conditions of these experiments, with plasma spectra taken at instants more than 10 times longer than total electrical current discharge.

Raman Scattering Enhancement by silver Nanostructures Prepared by Electrical Exploding Wire Technique

This project aims to fabricate nanostructures (AgNPS) using the electrical exploding wire (EEW) technique using Rhodamine 6G dye as the probe molecule, investigate the effect of AgNPS on the absorption spectra and surface-enhanced Raman scattering (SERS) activities, and advance using porous silicon as an active substrate for surface-enhanced Raman scattering (SERS). X-Ray diffraction (XRD) was used to investigate the structural properties of the nanostructures (AgNPs). Field emission scanning electron microscopy (FE-SEM) was used to investigate surface morphology. A double beam UV-Vis Spectrophotometer was used to analyze the mixed R6G laser dye(of concentration 1x M) absorption spectra with the nanostructures AgNPS (of concentration 24x M). A sunshine Raman microscope device (the objective lens used was (50x)). was used to analyze R6G combined with nanostructures Raman spectra. All samples have shown SERS activity that increased with increasing the hot spots. The SERS enhancement factor for R6G dye(of 1x10-6 M concentration) when mixed with (AgNPS) nanostructures has reached to(2.48 x 106) and the lowest detection limit reached to (1 x 10-14 M) at the wave number (1652 cm-1) using excited laser source (λexc. = 532nm)

Development of Effectual Substrates for SERS by Nanostructurs-Coated Porous Silicon

The current paper provides an efficient method for making active and effectual substrates used for detecting molecules by improving surface-enhanced Raman scattering (SERS). These substrates were fabricated using nanostructure-coated porous silicon. The nanostructures were prepared through the electrical exploding wire (EEW) technique. The silver nanowires (AgNWs) were coated with a polydopamine (PDA) layer to form an AgNWs@PDA colloidal solution. Then, the Ag wire was electrically exploded in the colloidal solution to form the (AgNWs@PDA@AgNPs) plasmonic nanostructures as a metal-insulator-metal. The effect of the plasmonic nanostructures’ morphologies on the absorptances spectra and SERS activities were studied utilising Rhodamine 6G (Rh6G) dye as examination molecules. X-ray diffraction (XRD) was used to investigate the structural properties of these nanostructures. Field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) were used to investigate the morphologies of these nanostructures. Atomic force microscopy (AFM) was used to study the surface topographies of SERS-effectual substrates. A double beam ՍV-Visible Spectrophotometer was used to measure Rh6G laser dye absorptance with a concentration of M) that mixed with the nanostructures at different concentrations. Sunshine Raman spectrometer with a (50 x) objective lens was used to analyse the Raman spectra of Rh6G Sunshine Raman spectrometer with a (50 x) objective lens was used to analyse the Raman spectra of Rh6G dye using a porous silicon substrate (PSi) on which silver nanowires are deposited (PSi-AgNWs). Another porous silicon substrate (PSi) on which nanostructures are deposited that consisting of silver nanowires, coated with a polydopamine layer, and decorated with silver nanoparticles are deposited (PSi-AgNWs@PDA@AgNPs). The results showed that hot spots and roughness on the nanostructures' surfaces caused an increase in intensities of absorptances spectra and signals of SERS. After the effectual substrates were excited by a (λexc.=532nm) laser source, the enhancement factor (EF) of SERS signals of Rh6G (1 M) attained (26.3 ) and (28.7 ) of the characteristic peaks at wavenumber (1650 ) for PSi-AgNWs and PSi-AgNWs@PⱰA@AgNPs effectual substrates respectively. This study showed that nanostructure-coated porous silicon substrates have a repeatable and high signal frequency, stability in storage, cost-low technique, and ease of use. They allow researchers to recognise and analyse a wide range of molecules, including biomolecules, with detection limits ranging between milli- and femtomolar. These effectual substrates have a bright future as a bioanalytical tool using SERS spectroscopy.

Tailoring magnetic properties through variation of cations distribution in Zn-Cu ferrite nanoparticles prepared by exploding wire technique

In this paper, Zinc-Copper ferrite nanoparticles, synthesized via a novel exploding wire technique. The Fe3+ cation distribution of tetrahedral and octahedral sites of prepared nanoparticles is estimated through intensity analysis of powder X-ray diffraction. The preference of Zn2+ and Cu2+ towards tetrahedral and octahedral sub-lattices and their influence on hyperfine magnetic lines are determined through Mössbauer spectroscopy. The cation distributions of Fe3+ at tetrahedral and octahedral sites of Fe2O3 powder used as precursor for the synthesis of samples are estimated through sextet’s areas. The existence of Fe3+ oxidation state Zn-rich Zn0.7Cu0.3Fe2O4 and Cu-rich Zn0.3Cu0.7Fe2O4 nanoparticles is ascertained through Mössbauer and electron spin resonance analysis. The ferroelectric properties are studied through polarization versus electric field analysis. Zero field cooling-field cooling investigation substantiated superparamagnetic behavior and demonstrated the variation of saturation magnetization with respect to Zinc/Copper concentration, as per Neel’s and Yafet-Kittel models.

Optical Emission Spectroscopy for Studying Fe Plasma Parameters Produced by Exploding Wire Technique in Carbon Nanotubes - Water Colloid

The goal of this work is to study plasma parameters for Fe plasma generated by exploding wire (EEW) in carbon nanotubes-water colloid with three current values (50, 100 and 150)A. In this research, the plasma electron temperature (Te), the electron density (ne), electron density (ne), plasma frequency(f p), Debye length (λD) and Debye number (ND) were found for Fe produced by Arc discharge plasma. Boltzmann plot was used to calculate the plasma electron temperature (Te);electron density (ne) was calculated from Stark broadening. It was found that the electron temperature values increased from (0.4134 _ 0.415) eV and the electron density increased from( 0.93 - 1.16)× 1017cm-3.

Supersonic jet by blast wave focusing

A supersonic jet of Mach number M = 4.5 in air is produced experimentally at the apex of a miniature 150 × 50 × 5 mm converging section with a 2 × 5 mm opening by the principle of blast wave amplification through focusing. An initial plane blast wave of M = 2.4 in the convergence section is generated by the exploding wire technique. The profile of the convergence section is specially tailored to smoothly transform a plane blast wave into a perfectly cylindrical arc, imploding at the apex of the section. The cylindrical form of the imploding shock delivers maximum shock amplification in the two-dimensional test section and maximum subsequent jet flow velocity behind the shock front. Blast wave propagation in the convergence chamber as well as jet generation through a 2 mm opening at the apex into the adjacent exhaust chamber is optically captured by a high-speed camera using the shadowgraph method. Visualizing the flow provided a distinct advantage not only for obtaining detailed information on the flow characteristics but also for validating the numerical scheme which further enhanced the analysis. Experimental images together with the numerical analysis deliver detailed information on the blast wave propagation and focusing as well as subsequent jet initiation and development. One of the main advantages of the described method apart from being simple and robust is the effective focusing of low initial input energy levels of just around 500 Joules, resulting in production of supersonic jets in a small confined chamber.

Preparation and characterization of graphene nanosheet doped with silver nanoparticles

Simple process (exploding wire technique) was used to Prepared sliver nanoparticles (AgNPs). The graphene sheet was added to AgNPs with different concentrations (0.002g/ml and 0.01g/ml). well dispersion of AgNPs are achieved by simple chemistry process. The samples were characterized by ultraviolet-visible spectroscopy (UV-Vis), x-ray diffraction (XRD), atomic force microscopy (AFM) and Field emission scanning electron microscope (FESEM). The results showed a wide band absorption of AgNPs-graphene (AgNPs-GN) extended from VU to IR region, surface plasmon resonance (SPR) absorption peak position for the AgNPs at (350-600) nm, XRD confirmed the clear distribution of the peaks attributed to polycrystalline for AgNPs appeared at 20=38.14°, 44.27°, 64.33, and 77.37° respectively and AgNPs-GN at 2θ=26.51° and 54.65°. The AFM showed that AgNPs have uniformly distribution on the surface of graphene sheet. The average size of AgNPs was confirmed by around (50-80) nm by FESEM and the AgNPs-GN have average particle size (20-40) nm. The AgNPs-GN could become prominent candidate for optoelectronic applications.

Structural, optical, magnetic and dielectric properties of magnetite (Fe3O4) nanoparticles prepared by exploding wire technique

Structural, optical, magnetic and dielectric properties of magnetite (Fe3O4) nanoparticles prepared by exploding wire technique

Study of the temperature and electron density of the cadmium sulfide plasma produced by the exploding wire technique using optical emission spectroscopy

The current study was conducted to reveal the most important parameters of the plasma which are the temperature and density of the electron, the plasma response, the Debye length and the number of particles inside the Debye sphere of the cadmium sulfide by a spectrometer. The results of the electron temperature (Te) and the electron density (ne) were discussed. The results of the cadmium sulfide plasma were discussed. It is generated by using the explosive wire and with different currents.

Significant magnetic, dielectric and magnetodielectric properties of CuO nanoparticles prepared by exploding wire technique

The CuO nanoparticles, prepared by exploding wire technique (EWT) followed by annealing in oxygen atmosphere at 900 °C, have been studied for phase purity and structure formation by employing X ray diffraction (XRD) method. Rietveld refinement and Debye-Scherrer analyses ensured the formation of monoclinic single phase of CuO nanoparticles with an average crystallite size of ~ 21 nm. Irregular shape nanoparticles in the size range of 5–30 nm were observed by Transmission Electron Microscopy. The temperature dependent (5–300 K) magnetization measurements have been performed to ascertain the magnetic properties of the prepared nanoparticles, which indicated the antiferromagnetic behavior around 230 K. The temperature dependent (10–300 K) dielectric measurements in 0 T and 1.3 T external magnetic fields demonstrated the frequency dependent dispersive behavior of CuO nanoparticles in the temperature range 100–200 K. The dielectric relaxation mechanism of CuO nanoparticles was further analyzed and found to follow the Arrhenius like behavior. Finally, we could observe that the Variable range hopping (VRH) is more precise in present case of CuO nanoparticles. Notably, the magnetodielectric response (MDR) of the order of 2.5 is also observed at 12 kHz frequency at the temperature around 150 K in the optimal magnetic field of 1.3 T. This proves to be an uncommon interesting property of prepared CuO nanoparticles and may lead to new technological applications.

The Effect of Plasmonic Nanostructures Prepared by Electrical Exploding Wire Technique on the Optical Properties of R6G Dye

The Effect of Plasmonic Nanostructures Prepared by Electrical Exploding Wire Technique on the Optical Properties of R6G Dye

Signature of Plasmonic Nanostructures Synthesised by Electrical Exploding Wire Technique on Surface-Enhanced Raman Scattering

This work aims to fabricate two types of plasmonic nanostructures by electrical exploding wire (EEW) technique and study the effects of the different morphologies of these nanostructures on the absorption spectra and Surface-Enhanced Raman Scattering (SERS) activities, using Rhodamine 6G as a probe molecule. The structural properties of these nanostructures were examined using X-Ray diffraction (XRD). The morphological properties were examined using field emission scanning electron microscopy (FESEM) and scanning transmission electron microscopy (STEM). The absorption spectra of the mixed R6G laser dye (concentration 1×10-6 M) with prepared nanostructures were examined by double beam UV-Vis Spectrophotometer. The Raman spectra of the R6G mixed with the prepared nanostructures were examined using a Horiba HR Evolution 800 Raman microscope system with an objective lens (50 ×). The FESEM and STEM images indicated that the Ag nanoparticles (AgNPs) with 35 nm average particle sizes were decorated on the surface of the AgNWs and the PDA layer by EEW technique, forming AgNW@AgNPs and AgNW@PDA@AgNPs nanostructures. The results indicated that the increased intensities of the absorption spectra peaks and the SERS arise from the hot spots and the roughness of the surface of nanostructures. The SERS enhancement factor of R6G (1×10-6 M) was reached at 2.3×107 and 2.5×107, at the wave number of 1650 cm-1, for the AgNW@AgNPs and AgNW@PDA@AgNPs nanostructures, respectively, after being excited by (λexc. = 532 nm) laser source. It can be concluded that the AgNW@AgNPs and AgNW@PDA@AgNPs nanostructures were fabricated with an easy and simple way without the need for additional chemical compounds. These nanostructures attained a reliable and sensitive detection and can be utilized in a variety of SERS applications, such as chemical and biological sensors.

Structural, magnetic and dielectric study of Fe2O3 nanoparticles obtained through exploding wire technique

We propose an exploding wire technique based facile approach to prepare Fe2O3 nanoparticles in ambient conditions. TG-DSC analysis of the prepared precursor (Fe(OH)3) nanoparticles were done. The phase, lattice parameter and the average crystallite size were evaluated through X-ray diffraction analysis. The morphology of prepared nanoparticles was studied by scanning electron microscopy and Transmission electron microscope. The functional group formation of Fe2O3 nanoparticles and intrinsic stretching vibration bands of Fe–O were estimated through FTIR analysis. The direct band gap of Fe2O3 nanoparticles occurring in conjunction with indirect band gaps was established via Tauc plot. The magnetic parameters were studied through Mössbauer spectroscopy, ESR, M-H and M-T plot analysis. The attributes of dielectric behaviour like dielectric constant (ε′), loss tangent (tan δ), dielectric loss (ε″) and alternating current (AC) conductivity (σAC) were measured at various temperatures in the frequency range of 10 Hz-106 KHz.

Au–Ag–Cu nanoparticles alloys showed antifangal activity against the antibiotics-resistant Candida albicans

Formation of Au–Ag–Cu ternary alloy nanoparticles (NPs) is of particular interest because its trimetallic process that includes miscible (Au–Ag and Au–Cu) and immiscible (Ag–Cu) system. So there is a possibility of phase segregation in this ternary system. At this challenge, it was an attempt to use the synthetic technique to generate such trimetallic alloy nanoparticles by exploding wire technique. This work aims to develop an effective antifungal treatment against the pathogenic fungus Candida albicans using Au–Ag–Cu nanoparticles alloys. In this work, three metals alloys (A, B, and C) containing Au–Ag–Cu nanoparticles were prepared as a physical methods by exploding wire with different ratio of each elements (A: 50% Au 25% Ag 25% Cu; B: 25% Au 50% Ag 25% Cu; C: 15% Au 60% Ag 25% Cu). The antifungal activity of the alloy nanoparticles was tested against pathogen fungi, Candida albicans grown on a solid medium using disk diffusion method. The highest antifungal activity against Candida albicans was observed on alloy B that was prepared by 160 A and concentrations 12.5 μg.ml-1. The treatment with this alloy showed more than 85% inactivation of the fungus growth.

Structural and optical properties of CdZnS nanoparticles by exploding wire technique

In this paper, we report the synthesis of CdZnS nanoparticles employing a low cost and facile novel approach based on Exploding wire technique (EWT). The particles obtained through this method were subjected to structural and optical characterization using X-ray diffraction (XRD) and UV–Visible spectroscopy. Formation of pure hexagonal phase CdZnS nanoparticles, along with an additional minority phase of CdS, is revealed by XRD analysis. Furthermore, dislocation density and lattice parameters and crystallite size of 35.8 nm was also determined for prepared nanoparticles. Notably, UV–visible spectrum and Tauc’ plot analysis not only ascertained the enhanced band gap of 3.59 eV nanoparticles but more significantly, established the predominant formation of ternary hexagonal phase CdZnS nanoparticles by our EWT based proposed synthesis route.

Magnetic and dielectric study of nanoparticles of Cu-ferrite prepared by explosion technique

In this article, the structural, surface morphology, dielectric and magnetic property of nanoscale Copper ferrite (CFO), synthesized by exploding wire technique (EWT) are studied. The sample is annealed at 650° for 7 h to remove impurities and defects. The structural analysis of XRD data confirms inverse spinel crystalline structure of average lattice parameter 8.41 Å. The homogenous and fine nanospheres of size varying from micro to nano dimensions are affirmed through micrographs of scanning electron microscopy (SEM). The real part of dielectric constant and dielectric loss (tan δ) as a function of frequency are studied. The sample exhibits high values of dielectric constant and dielectric loss in the form of heat at lower frequencies and saturate to lower value at high frequencies. The normal ferromagnetic behaviour of CFO at room temperature is established though magnetic characterization performed by (VSM) vibrating sample magnetometer. The values of remanence, coercivity and maximum obtained magnetization are evaluated.