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MM: Fachverband Metall- und Materialphysik
MM 55: Nanomaterials - Nanocrystalline & Porous Materials II
MM 55.4: Talk
Thursday, March 14, 2013, 12:30–12:45, H25
Synthesis of nanoporous gold for electrochemical actuators — •Yi Zhong1, Jürgen Markmann1,2, Hai-Jun Jin3, and Jörg Weissmüller1,2 — 1Institut für Werkstoffforschung, Werkstoffmechanik, Helmholtz Zentrum Geesthacht, Geesthacht, Germany — 2Institut für Werkstoffphysik und Technologie, Technische Universität Hamburg-Harburg, Hamburg, Germany — 3Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, P.R. China
Dealloying, an alloy corrosion process of gold alloys was used to fabricate nanoporous gold (npg) with a porosity up to 80 % and structural sizes, i.e. ligament diameters, down to a few nanometers. Particularly, the formation of macroscopic cracks has been investigated for two different starting alloy compositions, Au25Ag75 and Au25Cu75 which represent substitutional solid solutions with more or less identical atom size (Au-Ag) and very different atom size (Au-Cu). Apart from the dealloying potential, different pretreatments of the starting consequently provided completely different microstructural starting conditions and were compared with respect to their ability to suppress cracks in the resulting nanoporous structure. The resulting samples were crack-free with ligament sizes below 10 nm. Within different electrolyte environments, the amplitude of actuation of this npg could be tuned to values up to 0.89 %. Npg with such small ligament sizes are expected for application in electrochemical actuators of high functionality.