Metallic Muscles at Work: High Rate Actuation in Nanoporous Gold/Polyaniline Composites

Eric Detsi, Patrick Onck, Jeff Th. M. De Hosson*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

92 Citations (Scopus)


Metallic muscles made of nanoporous metals suffer from serious drawbacks caused by the usage of an aqueous electrolyte for actuation. An aqueous electrolyte prohibits metallic muscles from operating in dry environments and hampers a high actuation rate due to the low ionic conductivity of electrolytes. In addition, redox reactions involved in electrochemical actuation severely coarsen the ligaments of nanoporous metals, leading to a substantial loss in performance of the actuator. Here we present an electrolyte-free approach to put metallic muscles to work via a metal/polymer interface. A nanocoating of polyaniline doped with sulfuric acid was grown onto the ligaments of nanoporous gold. Dopant sulfate anions coadsorbed into the polymer coating matrix were exploited to tune the nanoporous metal surface stress and subsequently generate macroscopic dimensional changes in the metal. Strain rates achieved in the single-component nanoporous metal/polymer composite actuator are 3 orders of magnitude higher than that of the standard three-component nanoporous metal/electrolyte hybrid actuator.

Original languageEnglish
Pages (from-to)4299-4306
Number of pages8
JournalAcs Nano
Issue number5
Publication statusPublished - May-2013


  • nanoporous gold
  • polyaniline
  • electrolyte-free actuation
  • GOLD
  • SIZE
  • AREA

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