以低温水热法制备了TiO2-SnO2复合纳米晶粒,采用提拉法涂敷于带有金电极的氧化铝陶瓷管表面形成敏感薄膜,设计了一种新型薄膜式臭氧传感器。采用 X 射线衍射仪、热场发射扫描电子显微镜、能量色散X 射线谱仪和紫外-可见光谱能谱仪,表征了TiO2-SnO2纳米晶粒的晶体结构和微观形貌。采用紫外-可见吸收光谱法和电化学方法,讨论了TiO2-SnO2纳米晶粒对臭氧敏感机理与光电化学特性。在气体传感器静态测试系统上,采用XEDWS-60A型气敏元件分析仪测试了紫外光下臭氧传感器敏感特性、动态响应、抗干扰和稳定性。结果表明,以Ti与Sn摩尔比为6的TiO2-SnO2纳米晶粒为敏感薄膜的臭氧传感器,在相对湿度为40%和温度为25℃条件下,臭氧浓度为0.1~1.8μg/L时,有、无紫外光照射的臭氧传感器线性度分别为97.5%和78.5%,动态响应分别为2和9 s,恢复时间分别为5.5和15 s。此传感器对CO、NOx、甲醛、丙酮、丁醇和甲醇等气体具有良好的抗干扰性能。在汽车上连续使用12个月后,响应衰减了4.7%,响应正常时间为8.5个月。%TiO2-SnO2 composite nanocrystalline was prepared by the low temperature hydrothermal method. A new film-type ozone sensor was developed by using TiO2-SnO2 composite nanocrystallines transferred onto an alumina ceramic tube with Au electrodes by dip-coating method. The crystalline phase and microstructure of TiO2-SnO2 nanocrystallines were characterized by X-ray diffraction ( XRD) , field emission scanning electron microscope ( FE-SEM) , energy dispersive X-ray analysis ( EDAX) and ultraviolet-visible spectrometry ( UV-Vis) . The ozone sensitive mechanism and photoelectrochemical properties of TiO2-SnO2 nanocrystallines were analyzed by using ultraviolet-visible spectrometry and electrochemical method. These characteristic tests of ozone sensor were carried out on the traits of sensitive performance, dynamic response, interference and stability under ultraviolet-visible illumination by the XEDWS-60 A type multifunction analyzer in gas sensor static test system. the conclusion demonstrates that when the ozone sensor based on TiO2-SnO2 composite nanocrystalline ( molar ratio of Ti and Sn is 6 ) was under conditions of 40% relative humidity and 25 ℃operating temperature, when ozone concentration was increased from 0. 1 to 1. 8 μg/L, the best linearity of ozone sensor upon ultraviolet illumination and visible illumination were 97 . 5% and 78 . 5%, the dynamic response time was 2 s and 9 s, the recovery time was 5. 5 s and 15 s. This kind of sensor showed good anti-disturbance to the gases, such as CO, NOx , formaldehyde, acetone, butanol and methanol. The response value of ozone sensor was attenuated about 4 . 7%, when ozone sensor was applied continually on the automobile about 12 months, and its normal time was 8. 5 months.
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