Real-time Plant Health Monitoring System based on a Metal Oxide Semiconductor Gas Sensor Array

Plants express their health condition by emitting various gases, and the microbe-induced plant volatile (MIPV) is produced when plants become ill. Existing studies have limitations in that real-time plant health monitoring cannot be performed because the plant scent is analyzed using gas chromatography equipment. In this study, a real-time plant health monitoring system was developed by using a gas sensor array that can measure various gases in real-time and provide a more comprehensive view of plant health. First, as a preliminary experiment for selecting a sensing material, the reaction to geraniol was measured using a gas sensor made of three sensing materials (In
2
O
3
, SnO
2
, and WO
3
). In addition, a gas sensor array with In
2
O
3
coated with three catalysts (Au, Pd, Ag nanoparticles) was fabricated, and a gas test was performed on 2-phenylethanol, geraniol, and MeJA. The experimental results show that the three gases have different responses for each gas. Hence, in this study, plant health can be monitored in real-time by using the gas sensor array.