Synthesis of RuO2 Nanowires by Alkali-Assisted Oxidation of Ruthenium in Plasma Afterglow at Atmospheric Pressure

Duclair Kuete Saa, Thomas Gries, Sylvie Migot-Choux, Jaafar Ghanbaja, Pascal Boulet, Samuel Laminsi, Thierry Belmonte
2017 IEEE transactions on nanotechnology  
RuO2 nanowires are synthesized by oxidation of ruthenium thanks to a micro-post-discharge at atmospheric pressure. However, RuO2 nanowires form islands. The growth mechanism depending on surface defects, the surface density of the nanowires is limited. We report on the influence of two alkali salts, NaCl and KCl, deposited as grains on ruthenium to act as defects and increase the nanowire density. These grains induce the growth of RuO2 nanowires all around them, creating a circular area where
more » ... nowires are found. Nanowires start growing at the triple point at the grain base where the alkali-salt grain, ruthenium from the substrate and oxidizing gaseous species coexist. When nanowires grow, the stress induced in the surrounding layer creates new cracks, making possible the radial propagation of the nanowires. The presence of nanowires on grains is due to the etching mechanism that converts the alkali salt into an oxide, enabling onward oxidation of ruthenium. Index terms-1Ruthenium oxide, nanowires, plasma oxidation, afterglow, atmospheric pressure L This is the author's version of an article that has been published in this journal. Changes were made to this version by the publisher prior to publication. The final version of record is available at http://dx.
doi:10.1109/tnano.2017.2699861 fatcat:343cieito5hajkgwpzq4yzqpr4