A Micromachined Metal Oxide Composite Dual Gas Sensor System for Principal Component Analysis-Based Multi-Monitoring of Noxious Gas Mixtures

In-Hwan Yang; Joon-Hyung Jin; Nam Ki Min

doi:10.3390/mi11010024

A Micromachined Metal Oxide Composite Dual Gas Sensor System for Principal Component Analysis-Based Multi-Monitoring of Noxious Gas Mixtures

Micromachines (Basel). 2019 Dec 24;11(1):24. doi: 10.3390/mi11010024.

Authors

In-Hwan Yang¹, Joon-Hyung Jin¹, Nam Ki Min²

Affiliations

¹ Department of Chemical Engineering, Kyonggi University, 154-42 Gwanggyosan-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16227, Korea.
² Department of Electro-Mechanical Systems Engineering, Korea University, 2511 Sejong-ro, Sejong City 30019, Korea.

Abstract

Microelectronic gas-sensor devices were developed for the detection of carbon monoxide (CO), nitrogen dioxides (NO₂), ammonia (NH₃) and formaldehyde (HCHO), and their gas-sensing characteristics in six different binary gas systems were examined using pattern-recognition methods. Four nanosized gas-sensing materials for these target gases, i.e., Pd-SnO₂ for CO, In₂O₃ for NO_X, Ru-WO₃ for NH₃, and SnO₂-ZnO for HCHO, were synthesized using a sol-gel method, and sensor devices were fabricated using a microsensor platform. Principal component analysis of the experimental data from the microelectromechanical systems gas-sensor arrays under exposure to single gases and their mixtures indicated that identification of each individual gas in the mixture was successful. Additionally, the gas-sensing behavior toward the mixed gas indicated that the traditional adsorption and desorption mechanism of the n-type metal oxide semiconductor (MOS) governs the sensing mechanism of the mixed gas systems.

Keywords: dual-sensor system; metal oxide nanocomposite; microelectromechanical systems; noxious gas mixture.