![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
We report a strategy for preparing macroscopic samples of nanoporous (np-) Pd by electrochemical dealloying. Starting out with the master alloy , single-step dealloying in 1 M
at
C provides a hierarchical network structure with two well-defined ligament sizes, 35 and
10 nm. The material is distinguished by its uniform microstructure and its excellent mechanical deformability. Thereby, it may provide an alternative to dealloying-made nanoporous gold as a model system for nanoscale functional materials. Our study exemplifies this by exploring actuation through electrochemically controlled hydrogen sorption. Hydrogen underpotential deposition, bulk sorption isotherms and the concentration strain coefficient are found to agree closely with previous studies of H adsorption on planar surfaces and of hydrogen absorption in bulk, respectively. The actuation strain reaches amplitudes up to 4.0%. Even though each strain cycle brings the np-Pd-H through the
phase transformation, the strain amplitude remains stable during much more than 1000 cycles. Furthermore, in view of the macroscopic sample size in all three dimensions, the switching time for actuation is remarkably fast.
Acknowledgements
S. Shi acknowledges support by the Chinese Scholarship Council. We thank Dr. M. Ritter, J. Timmermann and Dr. J. Shen for assistance with scanning electron microscopy.
Notes
No potential conflict of interest was reported by the authors.
Supplemental data for this article can be accessed http://dx.doi.org/10.1080/14786435.2017.1311428.
