Study on the Gas Sensitivity Properties of TiO2 Nanoparticles Modified by ZnO

Abstract

TiO2 nanomaterials and ZnO doped TiO2 nanomaterials were synthesized by sol-gel method. The gas sensing properties of ZnO-doped TiO2 nanomaterials were investigated by using a parathermal gas sensor. Studies have shown that the responsiveness of ZnO-doped gas sensor to ethanol gas is increased from 80% to 87%, and the response recovery time is shortened to (1.5s, 1s). This method improves the gas sensitivity of the sensor. Introduction With the increasing emphasis on environmental protection, higher requirements are placed on the detection and monitoring of industrial waste gas, toxic and harmful gases, and the research of gas sensor has become an important research topic [1-3]. Semiconductor gas sensors have been widely studied due to their small size, low cost, simple structure, simple preparation and long service life. At present, the widely used gas sensor materials are ZnO and TiO2, which have good sensitivity to many gases such as ethanol, methane, hydrogen sulfide, carbon monoxide, etc. [4-9], semiconductors made of ZnO and TiO2. Gas sensors can be widely used in the monitoring of toxic gases in various fields of production and living. Generally, gas sensing elements prepared by using pure semiconductor metal oxide powder have low sensitivity, high operating temperature, and difficult performance to meet applicable requirements. At present, the gas of semiconductor metal oxides is mainly improved by methods such as compounding and doping [10]. Sensitive performance. Taking TiO2 as an example, the doping of elements can significantly change the band gap energy of TiO2 and lead to diversified physicochemical properties, thereby improving the detection performance of the sensor on the target gas. By doping the TiO2 gas sensitive material, the sensitivity can be greatly improved.