Gas Sensing Properties Of In-Doped ZnO Nanorods For Ethanol

ZnO is the most widely used gas sensitive material. It is common, abundant,non-toxic harmless, so ZnO is a kind of ideal gas sensitive materials. However,traditional ZnO materials have some disadvantage, such as low sensitivity, poor selectivity and high working temperature, we usually change morphology or dope other metallic element to improve their gas sensitive properties.In his paper, we prepare ZnO nanorods materials and In-doped ZnO nanorods marerials by sol-gel to improve gas sensitive properties of ZnO material for ethanol.Firstly, prepare ZnO sol and 2at.%, 3at.%, 4at.% In-oped ZnO sol and spin them on the interdigital electrode respectively. After drying pretreatment and high temperature annealing, we gain gas sensitive element made by different ZnO materials.Then we begin to test these samles by test system made by ourselves.When working temperature is 300?, the sensitivity of the ZnO nanorods on the same concentration of ethanol gas is higher than the traditional ZnO thin film materials,the sensitivity of 3at.% In-ZnO nanorods film on the same concentration of ethanol gas is higher than the undoped and 2at.% and 4at.% In-ZnO nanorods films, which indicates that nanorods and the dopement of In element increase the sensitivity to ethanol, and the best doping content is 3at. %. Under different temperature, we measure the response of different samples to 200 ppm ethanol gas. We find the best working temperature of undoped ZnO nanorods films is 350 ?, and In-doped ZnO nanorods films is325?,which indicates that the dopement of In element reduce the working temperature.The selectity, response, recovery time and repeatability were also tested. Through analysis and comparison, the conclusion of results is that In-doped ZnO nanorods material shows a better gas sensitive performance relative to the undoped ZnO nanorods and traditional of ZnO materials.