Actuating and sensing properties of nanoporous gold.
We show that variations in the relative humidity give rise to reversible macroscopic dimensional changes in nanoporous gold exposed to ambient air. The macroscopic strain is the consequence of changes in the nanoporous gold surface stress. We have measured reversible strain amplitudes up to 0.02% in response to a 15% change in relative humidity. The direct conversion into mechanical work of the energy involved in the liquid to vapor phase transition of water is attractive for environmentally friendly short-stroke actuator and sensor applications.
Department of Applied Physics, Zernike institute for Advanced Materials and Materials Innovatrion Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
E
E
Detsi
Z G
ZG
Chen
W P
WP
Vellinga
P R
PR
Onck
J T M
JT
De Hosson
D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D006813:Humidity; D008422:Materials Testing; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D009038:Motion; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D016062:Porosity; D013314:Stress, Mechanical; D014159:Transducers; D014867:Water / Q000737:chemistry*
D014867:Water; D006046:Gold