Nanoparticles formed by spark discharge and by laser ablation
Résumé
Both laser ablation and spark discharge techniques are promising green methods of nanoparticle (NPs) formation [1, 2, 3]. The produced particles have found numerous applications in such areas as electronics, biomedicine, textile production etc. The main advantages of laser ablation are in the possibilities of control over laser ablation process, whereas the ones of spark discharge are in the possibility to use these discharges in parallel and to increase nanoparticle yield.
To optimize NP production processes, we consider different stages involved and analyze the resulting plasma and nanoparticle parameters. Based on the performed calculations, such properties as mean size and mean density are calculated.
The performed analysis shows how the experimental conditions are connected with the resulted nanoparticle characteristics in agreement with several previous experiments. The dynamics of plasma expansion is shown to govern primary nanoparticle formation in the presence of a gas. After well-defined delays, particles start appearing. In fact, a mixture of the evaporated vapor with a much the background gas leads to a strong supersaturation. Such processes as nucleation, collision growth and coalescence are accounted for.
The obtained size distributions agree with the available experimental results obtained by the partners of EU project BUONAPART-E.
[1] T. E. Itina, Modeling nanoparticle formation by laser ablation and by spark discharges. SPIE LASE. International Society for Optics and Photonics, 2016. p. 973704-973704-6.
[2] T.E. Itina and A. Voloshko, Nanoparticle formation by laser ablation in air and by spark discharges at atmospheric pressure, Appl. Phys. A. vol. 113, no3, pp. 473-478 (2013).
[3] T.E. Itina and A. Voloshko, "Nanoparticle formation by laser ablation and by spark discharges: properties, mechanisms and control possibilities."Nanoparticles Technology (2015).