Gas Sensor Based On Noble Metal-doped ZnO

In the context of the development of the society towards the direction of intelligence and informatization,the Internet of things technology has accelerated the process of change in all walks of life and provided great help for it.As the "gateway" of the Internet of things,sensor is a kind of detection device that converts the measured signal into electrical signal.To some extent,the performance of sensor directly affects the development of Internet of things technology.With the explosive development of all walks of life,toxic and harmful gases are also increasing.This is not only a threat to people's property security,but also a threat to people's own security.With the strong demand of people,gas sensors are actively developed by researchers.SMO gas sensor is a kind of gas sensor,which is famous for its low cost,simple manufacturing process,fast response speed,good selectivity,high sensitivity and small volume.However,there are several shortcomings that restrict SMO gas sensor.First,a higher detection limit and a narrower detection range.Secondly,SMO gas sensor is greatly affected by the surrounding environment and has weak anti-interference ability.In this paper,ZnO based gas sensors are prepared by hydrothermal synthesis method.Noble metal doping is used to improve the gas sensing performance of gas sensors,and the mechanism is explained.The main research contents include:1.ZnO nanorods were successfully synthesized by hydrothermal method,and the gassensing properties of ethanol gas based on ZnO nanorods were investigated.The experimental results show that when the optimal working temperature is 250?,the sensitivity of Z3 based sensor for ethanol gas is the highest,about 2.1,and the response time is 16 s.In addition,at the optimal operating temperature of 250?,the sensor has good selectivity,repeatability and low detection limit for ethanol gas.2.Noble metal(Ag,Pd)doped ZnO was synthesized by hydrothermal method with low cost and easy operation.The Ethanol Sensor Based on Ag-ZnO nanorods and the gas sensor based on Pd-ZnO were fabricated.The gas sensing characteristics of the sensor to ethanol gas were compared and analyzed.The results of gas sensing test show that the gas sensing performance of Ethanol Sensor Based on 3at% Ag-ZnO nanorods and Pd-ZnO Gas sensor is the best at 250?.At the same time,it has low detection limit,good selectivity and excellent repeatability.