PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.
Dispersions of small catalyst particles on metal oxide sensitive layers are commonly used as catalytic activators in gassensing
devices. Platinum and palladium are a well known catalyst, but their capability to increase the selectivity of
metal oxide gas sensors is however far from being well understood and is thus still a matter of investigation. One recent
trend is the size reduction of the catalyst particles.
We present an approach to optimize the specific response to gases by using specially prepared nano-sized palladium
clusters on highly dense sputtered polycrystalline SnO2. For the deposition of the palladium clusters energetic cluster
impact technique is used. Using this deposition technique, charged clusters are accelerated by an electric field of several
keV and directed onto the substrate. The deposited clusters consist of 3000 palladium atoms in average, forming clusters
of approx. 4 nm in diameter.
Structural and morphological analyses were performed. Gas measurements were carried out. The Pd-nano-clusters
covering the sensitive layer significantly affect the gas sensitivities and the corresponding dynamic response. For
example the sensors reaction to CO exposure is significantly different in two points in comparison to a sensor without
nano-sized clusters: even at room temperature CO can be detected and the sensitivity is increased at all investigated
operation temperatures of the sensor.
Nevertheless the CO sensitivity maximum still is around 400 °C, which corresponds with the maximum of O- adsorption
on the surface. Palladium acts as a catalyst for dissociating O2- to O-.
Stefan Palzer,Emmanuel Moretton,Chunrong Yin,Bernd von Issendorf, andJürgen Wöllenstein
"On the influence of nano-sized palladium clusters at the surface of SnO2 thin films on the gas response", Proc. SPIE 6589, Smart Sensors, Actuators, and MEMS III, 65891J (17 May 2007); https://doi.org/10.1117/12.722018
ACCESS THE FULL ARTICLE
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.
The alert did not successfully save. Please try again later.
Stefan Palzer, Emmanuel Moretton, Chunrong Yin, Bernd von Issendorf, Jürgen Wöllenstein, "On the influence of nano-sized palladium clusters at the surface of SnO2 thin films on the gas response," Proc. SPIE 6589, Smart Sensors, Actuators, and MEMS III, 65891J (17 May 2007); https://doi.org/10.1117/12.722018