National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Key Laboratory for Thin Film and Microfabrication of Ministry of Education, Department of Micro/Nano Electronics, School of Electronic information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
ACS Sens. 2020 Apr 24;5(4):994-1001. doi: 10.1021/acssensors.9b02458. Epub 2020 Mar 25.
Although volatile organic compound samples can be detected by gas nanosensors in adsorption principles, extreme concentrations of target gases imply the excessive adsorption, which would lead to a long recovery time and even a shortened lifetime. Herein, we report the observations of the ionization current sensing behavior on the volatile organic compounds in an ionization gas sensor with silicon-based nanostructures. The micro ionization gas sensor consists of a pair of silicon microneedle array electrodes covered by nanolayer structures and a microdischarge gas gap. The dynamic response behaviors of the sensors to the exposure of ethanol, acetone, and 2-chloroethyl ethyl sulfide have been carefully scrutinized. The sensor exhibits sound performances to the high-concentration volatile organic compounds with a fast-recovery property and could generate effective responses well at 36 V, namely, the safety operation voltages. It could be well understood by the Jesse effect where small proportion of impurities in gases could lead to an intensive increase in the overall ionization probability. Besides, the reproducibility, recovery time, sensitivity, and selectivity properties have been systematically characterized.
虽然气体纳米传感器可以通过吸附原理检测挥发性有机化合物样品，但目标气体的极端浓度意味着会过度吸附，这将导致较长的恢复时间，甚至缩短传感器的使用寿命。在此，我们报告了在具有硅基纳米结构的电离气体传感器上对挥发性有机化合物的电离电流感应行为的观察。微电离气体传感器由一对硅微针阵列电极组成，这些电极覆盖有纳米层结构和微放电气体间隙。我们仔细研究了传感器对乙醇、丙酮和 2-氯乙基乙基硫醚暴露的动态响应行为。该传感器对高浓度挥发性有机化合物具有良好的性能，具有快速恢复特性，在 36V 时可产生有效的响应，即安全工作电压。这可以通过杰西效应来很好地理解，即气体中的小比例杂质会导致整体电离概率的剧烈增加。此外，还系统地表征了重复性、恢复时间、灵敏度和选择性特性。
