High temperature oxygen sensors are widely used for exhaust gas monitoring in automobiles. This particular study explores the use of thin film single crystalline samaria doped ceria as the oxygen sensing material. Desired signal to noise ratio can be achieved in a material system with high conductivity. From previous studies it is established that 6 atomic percent samarium doping is the optimum concentration for thin film samaria doped ceria to achieve high ionic conductivity. In this study, the conductivity of the 6 atomic percent samaria doped ceria thin film is measured as a function of the sensing film thickness. Hysteresis and dynamic response of this sensing platform is tested for a range of oxygen pressures from 0.001 Torr to 100 Torr for temperatures above 673 K. An attempt has been made to understand the physics behind the thickness dependent conductivity behavior of this sensing platform by developing a hypothetical operating model and through COMSOL simulations. This study can be used to identify the parameters required to construct a fast, reliable and compact high temperature oxygen sensor.
Revised: July 25, 2020 |
Published: January 1, 2011
Citation
Sanghavi R.P., M.I. Nandasiri, S.N. Kuchibhatla, W. Jiang, T. Varga, P. Nachimuthu, and M.H. Engelhard, et al. 2011.Thickness Dependency of Thin Film Samaria Doped Ceria for Oxygen Sensing.IEEE Sensors Journal 11, no. 1:217-224.PNNL-SA-69764.doi:10.1109/JSEN.2010.2050766