Abstract
In this work, we present a novel approach for preparing atom probe tomography (APT) specimens from Pd electrocatalyst nanoparticles of less than 10 nm in size. This method is based on electrophoresis of nanoparticles on a substrate followed by electroplating of a metallic layer. Using transmission electron microscopy (TEM) we could observe that particle shape and size were well preserved after these two process steps. We could routinely prepare APT specimens from the deposited nanoparticle/metal films using focused-ion- beam milling (FIB). Using APT we were not only able to map the elemental distribution within the nanoparticles but also the distribution of surfactants i. e. stabilizing and shape-controlling agents, used in the synthesis of the nanoparticles.
