We report the effects of various tensile velocities on the nanocrack formation in a Pd thin film on an elastomeric polydimethylsiloxane substrate and its H2 sensing properties. A tunable nanocrack along the x and y axes was created by mechanical stretching/compression cycles with varying tensile velocities. From the microstructural analyses, we found that the tensile velocity has a significant effect on the crack density but little effect on the average crack width. The Pd nanogap sensor prepared under a high tensile velocity showed a high performance with a low detection limit of 500 ppm of H2 in air. Our results indicate that the higher crack density with the narrow nanocrack width (55-100 nm) propagated over the entire film provides the enhanced H2 sensing properties in air.
Bibliographical noteFunding Information:
This work was supported by the Priority Research Centers Program through the National Research Foundation of Korea (NRF) (2009-0093823).
© 2016 Elsevier B.V. All rights reserved.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry