Letter abstract
Nature Materials 8, 47 - 51 (2009)
Published online: 30 November 2008 | doi:10.1038/nmat2335
Subject Categories: Sensors and biosensors | Nanoscale materials | Porous materials | Surface and thin films
Surface-chemistry-driven actuation in nanoporous gold
J. Biener1, A. Wittstock1,2, L. A. Zepeda-Ruiz1, M. M. Biener1, V. Zielasek2, D. Kramer3, R. N. Viswanath3, J. Weissmüller3, M. Bäumer2 & A. V. Hamza1
Although actuation in biological systems is exclusively powered by chemical energy, this concept has not been realized in man-made actuator technologies, as these rely on generating heat or electricity first1. Here, we demonstrate that surface-chemistry-driven actuation can be realized in high-surface-area materials such as nanoporous gold. For example, we achieve reversible strain amplitudes of the order of a few tenths of a per cent by alternating exposure of nanoporous Au to ozone and carbon monoxide. The effect can be explained by adsorbate-induced changes of the surface stress2, and can be used to convert chemical energy directly into a mechanical response, thus opening the door to surface-chemistry-driven actuator and sensor technologies.
- Nanoscale Synthesis and Characterization Laboratory, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
- Institut für Angewandte und Physikalische Chemie, Universität Bremen, 28359 Bremen, Germany
- Institut für Nanotechnologie, Forschungszentrum Karlsruhe, 76021 Karlsruhe, Germany
Correspondence to: J. Biener1 e-mail: biener2@llnl.gov
