Using Sol-Gel and Hydrothermal Method to Fabricate ZnO Nanostructure and its Gas Sensing Application

• Main Authors: Ching-Feng Li, 李青峰
• Other Authors: Yuan-Yao Li
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/57837700072727686881

碩士 === 國立中正大學 === 化學工程研究所 === 101 === In this study, ZnO was synthesized on SiO2 substrate and Microelectromechanical system was conducted to fabricate the gas sensors. The performance of gas sensors was demonstrated using a diluted NH3 in a variety of operational conditions. The experiments are divided into two parts The first part is to synthesize ZnO thin film via sol-gel method. The highest sensitivity was observed at 150 oC and the sensitivity was decreased with the operation temperature from 150 to 300 oC. In order to realize the sensing mechanism of ZnO thin film, the oxygen ratio in the carrier gas and the sensing area of ZnO thin film was varied. It was observed that the gas sensing characteristics such as response time, recovery time, and sensitivity depend on the gas concentration and temperature. The second part is to synthesized ZnO nanorod gas sensor via photolithography and hydrothermal method .The ZnO nanorods have a length longer than 2 um and diameters of 300±100 nm. The best gas sensing performance of ZnO nanorod was found at 250 oC and the sensitivity was about 46.4%.