AIT Austrian Institute of Technology, Donau-City-Strasse 1, Vienna, Austria.
Nanotechnology. 2013 Aug 9;24(31):315501. doi: 10.1088/0957-4484/24/31/315501. Epub 2013 Jul 12.
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.
在这项工作中，我们给出了二氧化锡单纳米线气体传感器中一氧化碳吸附/解吸过程的动力学参数的计算数值。在不同温度下研究了这种传感器对氮气中 50ppm 一氧化碳脉冲的响应，以提取所需信息。速率方程方法用于模拟反应动力学，这导致了在耦合非线性常微分方程组中确定系数的问题。数值通过逆模型技术计算，然后用于模拟传感器响应。通过我们的模型，可以研究由于气体-表面相互作用而导致的传感器的动态响应，以找到用于检测的最佳设置，这是这些器件选择性的重要步骤。我们还研究了纳米线中电流的噪声及其由于传感器环境中存在一氧化碳而发生的变化。在这里，我们提出使用小波变换来分解信号并分析实验数据中的噪声。该方法表明，一些波动是针对这里研究的气体种类特有的。
