Nano-droplet ejection and nucleation of materials submitted to non-thermal plasma filaments

J.-P. Borra (1) , N. Jidenko (1) , C. Dutouquet (2) , O. Aguerre (2) , J. Hou , A. Weber

1 LPGP - Laboratoire de physique des gaz et des plasmas
2 INERIS - Institut National de l'Environnement Industriel et des Risques

Methods to induce non-thermal atmospheric pressure plasma filaments are presented with related properties for micro, streamer and prevented spark discharges, respectively, induced in planar Dielectric Barrier Discharges with one electrode covered by dielectric material (mono-DBD) or point-to-plane Corona. Two mechanisms of nano-particles formation are depicted from aerosol size distributions and TEM analysis. 0.1-10 mJ prevented spark discharges produce 10-100 nm droplets ejected from melted craters as well as nucleated primary particles and subsequent 10-100 nm agglomerates, by nucleation and coagulation in expanding vapor jets. With smaller energy per filament, 0.1-10 J micro-discharges and 0.1-100 J streamers, the initial local vapor fluxes emitted from spots of interaction between plasma filaments and electrodes are reduced. Subsequent smaller primary particle density limits the local coagulation in the vapor plume since 2-10 nm non-agglomerated crystalline metal nano-particles are produced in mono-DBD with Au, Ag and Cu electrode. Besides, the evolution of the aerosol size from primary nano-particles to agglomerates with transit time suggests slow coagulation of these primary metal particles in mono-DBD. Aerosol properties depend on the energy per filament and on the electrode. The final size is controlled by plasma parameters and transit time in and after the plasma. The aim is to underline emerging applications of atmospheric pressure plasmas for the production of tailored particles with tunable size, composition and structure with non-thermal plasma filaments to control the resulting properties of nano-powders and materials. Production rates and related energetic yields are compared.

Mots clés: Physical Sciences

Domaines: Physique [physics]

J.-P. Borra, N. Jidenko, C. Dutouquet, O. Aguerre, J. Hou, et al.. Nano-droplet ejection and nucleation of materials submitted to non-thermal plasma filaments. European Physical Journal: Applied Physics, 2011, 56 (2), pp.24019. ⟨10.1051/epjap/2011110201⟩. ⟨hal-00746219⟩