Protecting of Nanoscaled nonoxidic Particles from Oxygen Uptake by Coating with Nitrogen Containing Surfactants

To suppress the reactivity of nanoscaled powders titaniumnitride, titaniumcarbide and siliconcarbonitride with oxygen and water, chemical surface modification with nitrogen containing surfactants was investigated.Among these surfactants long chain primary amines, ethylen diamines, guanidines, nitriles und succinimides were examined.It was found, that the oxygen uptake of the treated powders decreased as the number of carbon atoms in nitrogen containing surfactants increased. Significant differences in the protection efficiency according to the polar head groups of the surfactants were observed.Chemical stability increased within the following sequence:Nitrile<succinimide<guanidine<primary amine<ethylene diamine.r