Qi, ZhenZhenQiVainio, UllaUllaVainioKornowski, AndreasAndreasKornowskiRitter, MartinMartinRitterWeller, HorstHorstWellerJin, Hai-JunHai-JunJinWeissmüller, JörgJörgWeissmüller2019-12-162019-12-162015-03-16Advanced Functional Materials 17 (25): 2530-2536 (2015)http://hdl.handle.net/11420/4124© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. A preparation strategy is developed for monolithic samples of nanoporous gold with a hierarchical structure comprising two nested networks of solid "ligaments" on distinctly different structural length scales. The electrochemical dealloying protocol achieves a large retention of less noble element in a first corrosion step, thereby allowing an extra corrosion step which forms a separate structural hierarchy level. The beneficial impact of adding Pt to the Ag-Au master alloys that are more conventionally used in dealloying approaches to nanoporous gold is demonstrated. At ≈6 nm, the lower hierarchy level ligament size emerges extremely small. Furthermore, Pt favors the retention of Ag during the first dealloying step even when the master alloy has a high Au content. The high Au content reduces the corrosion-induced shrinkage, mitigating crack formation during preparation and favoring the formation of high-quality macroscopic (mm-sized) samples. The corrosion effectively carves out the nanoscale hierarchical ligament structure from the parent crystals tens of micrometers in size. This is revealed by X-ray as well as electron backscatter diffraction, which shows that the porous crystallites inherit the highly ordered, macroscopic crystal lattice structure of the master alloy.en1616-302820151725302536Wiley-VCHhttps://creativecommons.org/licenses/by-nc-nd/4.0/Ag-Au-Pt alloysdealloyingnanoporous metalstructural hierarchyChemieIngenieurwissenschaftenJournal Article10.15480/882.254210.1002/adfm.20140454410.15480/882.2542Journal Article