Vacuum as a continuum medium forming energy inhomogeneities with high energy density in the liquid phase

A method for the formation of metal nanoparticles in a localized volume with a high energy density due to the flow of a pulsed electric discharge and the effect of cavitation has been studied. The mechanism of formation of energy inhomogeneities, which provides the generation of nanoparticles with high specific energy intensity, is considered. The formation of dynamic heterogeneity is carried out in three stages. There is a breakdown of the interelectrode space and the formation of a vacuum volume, which is filled with a vapor-gas medium. As a result of an increase in pressure in the bubble, a pulsed gas discharge is ignited, which leads to the generation of metal nanoparticles. As a result, there is a localized volume in which the energy in the discharge reaches a value of up to 10⁶ K. The growth of energy in the bubble leads to its collapse and metal nanoparticles pass from a medium with high energy (10⁶) into water at room temperature, which leads to their hardening. Particularly pure nanoparticles of various metals with a size of 5–15 nm are obtained, which can be grown on a single-crystal silicon surface at room temperature and positioned on the surface of porous materials and products of complex configuration.

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