B1.2 Sensitivity and Selectivity of Pd based Thin Film Hydrogen Sensors
- Event
- SMSI 2020
-
(did not take place because of Covid-19 virus pandemic) - Band
- SMSI 2020 - Sensors and Instrumentation
- Chapter
- B1 Hydrogen Sensors
- Author(s)
- M. Wienecke, L. Godenrath, M. Hoffmann - Materion GmbH, Wismar (Germany), J. Heeg - Hochschule Wismar, Wismar (Germany)
- Pages
- 95 - 96
- DOI
- 10.5162/SMSI2020/B1.2
- ISBN
- 978-3-9819376-2-6
- Price
- free
Abstract
Pd-based thin film hydrogen sensors are available on the market since several years. They run due to different physically mechanisms, such as optical switching, changing resistance or capacity of thin film structures. This article describes the capabilities of Pd-thin film optical sensors (POS) and of new micro-electromechanical systems (MEMS). MEMS Pd-based sensors utilise the volume change of Pd due to the hydrogenation, thus they switch mechanically. Both systems detect hydrogen concentrations between 100 vol.-ppm and 100 vol.-% hydrogen in any gas mixtures. They show low cross sensitivities and particularly no cross sensitivity to methane (CH4) since the switching mechanism is a physical one. The response time (t90) for POS and MEMS sensors is about 20 s and 5 s, respectively. Thus, both senso