In this work, we present calculated numerical values for the kinetic parameters governing adsorption/desorption processes of carbon monoxide at tin dioxide single-nanowire gas sensors. The response of such sensors to pulses of 50 ppm carbon monoxide in nitrogen is investigated at different temperatures to extract the desired information. A rate-equation approach is used to model the reaction kinetics, which results in the problem of determining coefficients in a coupled system of nonlinear ordinary differential equations. The numerical values are computed by inverse-modeling techniques and are then used to simulate the sensor response. With our model, the dynamic response of the sensor due to the gas-surface interaction can be studied in order to find the optimal setup for detection, which is an important step towards selectivity of these devices. We additionally investigate the noise in the current through the nanowire and its changes due to the presence of carbon monoxide in the sensor environment. Here, we propose the use of a wavelet transform to decompose the signal and analyze the noise in the experimental data. This method indicates that some fluctuations are specific for the gas species investigated here. © 2013 IOP Publishing Ltd.
|Original language||English (US)|
|State||Published - Jul 12 2013|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This work was supported by the WWTF (Vienna Science and Technology Fund) high-potential project no. MA09-028 and by award no. KUK-I1-007-43 funded by the King Abdullah University of Science and Technology (KAUST). The computations were performed on the Vienna Scientific Cluster (VSC). The authors acknowledge Christian Gspan from the Institute for Electron Microscopy and Fine Structure Research, Graz University of Technology, and Center for Electron Microscopy Graz for the TEM analyses.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.