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.
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 cavitation effect was studied. The mechanism of the formation of energy inhomogeneities providing for the generation of nanoparticles with a high specific energy intensity was considered. Dynamic heterogeneity forms in three stages. There is a breakdown of the inter-electrode gap and the formation of a vacuum volume filled with a vapor-gas medium. When the pressure inside the bubble increases, a pulsed gas discharge is ignited, thus generating metal nanoparticles. This leads to the formation of a localized volume in which the discharge energy reaches values of up to 106 K. The increase in energy in the bubble leads to its collapse, after which the metal nanoparticles pass from the high-energy (106) medium into water at room temperature, resulting in their hardening. Highly pure nanoparticles of various metals 5–15 nm in size are obtained; these 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.
The influence of parameters of high-voltage electric spark dispersion of materials on the granulometric composition of nanopowders of metals and alloys is considered. The most interesting feature of the developed experimental setup is the presence of an air discharge gap (FV1), which creates an overvoltage on the working discharge gap (FV2). The discharge gaps form a voltage divider when the capacitor (C) is discharged. It was assumed that the voltage divider should have a significant impact on the operation of the experimental setup. Studies have shown that when the air gap (FV1) is much larger than the working gap (FV2), their exact ratios do not affect the size of the resulting nanoparticles. At such ratios of discharge gaps, the voltage divider allows to regulate only the performance of the process of obtaining nanopowders. The resulting silver nanopowders had a spherical shape and a rather narrow size distribution. It is necessary to further study the process of high-voltage spark dispersion of materials with a significant overvoltage of the discharge gap.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.