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This paper presents a novel single-step method for preparation copper nanofluids by electrical explosion of wire in liquid. Three types of fluids were used as a medium of the wire explosion process: deionised water, cetyl trimethyl ammonium bromide (CTAB) solution 0.001 M and ethylene glycol. The X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), energy dispersive spectroscopy (EDS) and UV-vis spectroscopy were used to investigate the properties of the nanofluids. Pure copper phase was detected in the nanofluids using ethylene glycol and mixture of copper and oxide phase was observed in the nanofluids using water and CTAB solution. FE-SEM analysis showed that size of particles formed in ethylene glycol was about 90 nm, the smallest in three samples.

In this study, gold nanocolloid was produced via the electrical explosion of wire in water, for the purpose of medical treatment. Thus, the use of other additives was avoided to stabilize the gold nanocolloid. The temperature of the water that was to be used for explosion was changed, and its effect on the stability of the gold nanocolloid was investigated. The synthetic temperature was varied from ice temperature to 80 degrees C. The morphology and particle size were studied using a transmission electron microscope. The UV-Vis spectra confirmed the formation of gold nanoparticles in the water. The stability of the gold nanocolloid was estimated using the zeta-potential and Turbiscan methods. The results showed that the synthetic temperature affected the stability of the gold nanocolloid. The TEM images of the gold nanoparticles prepared at low temperatures (0 and 20 degrees C) have several big particles. But, when the synthetic temperature was increased to 80 degrees C, most of the nanoparticles formed a spherical shape, without neck connection. Better stability was obtained in the gold nanocolloid sample prepared at a higher temperature. The gold nanocolloid that was synthesized at 80 degrees C was stable for more than three months, with small sedimentation.

The electroexplosive route for nanopowders production is a rapidly occurring nonequilibrium process under the action of high power density energy. The electrical explosion of conductor (EEC) powder particles have a spherical shape with protective oxide-hydroxide layer which is an adsorbed layer of working gas on the surface of particles. The formation of EEC end products (nanopowder) occurs in conditions of coexistence of metal in different states: the vapor form (cluster), plasma and superheated liquid. In this work, the formation of particles and excess energy stored during EEC were studied. Themal analysis is suggested as a method for the determination of excess energy value. According to the results of the thermal analysis, the excess energy value for nanosized aluminum powder with various storage time after passivation are 61.99-11.89 kJ/mole, respectively.