基于水热法制备的ZnO纳米棒的CO传感器 = CO gas sensor based on ZnO nanorod array grown by hydrothermal decomposition

Abstract

纳米结构的氧化锌(ZnO)可以吸附大量的气体,并且在吸附了气体之后形成特定的表面态,从而对其导电性产生显著的影响.用水热法在ITO电极之间制备了ZnO纳米棒阵列,通过扫描电镜(SEM)、X射线衍射(XRD)和高分辨透射电镜(HRTEM)等表征后发现,制得的ZnO纳米棒具有较好的结晶性.在200℃下,当1.2mg/L的CO气体通过ZnO纳米棒时,ITO电极两端的电流发生了较明显的改变,显示该装置对CO气体具有较明显的响应(灵敏度为18).可以预见通过改变电极之间生长的ZnO纳米结构形貌,提高纳米结构的表面利用率,以及适当提高测试温度,可以进一步提高传感器的灵敏度.制作的气体传感器具有简单、廉价、环保的特点,对于气体传感器的设计提供了新的思路. Zinc oxide(ZnO) in nanostructure has the feature to adsorb great amount of gas in order to form a certain kind of surface state.The electronic conductivity of ZnO nanorod experiences a considerable change during the process of adsorption.In this work,gas sensor was fabricated from ZnO nanorod arrays prepared via a facile hydrothermal decomposition on Indium Tin Oxide(ITO) glass.The ZnO nanorods show very good crystalline characterized by Scanning Electronic Microscopy(SEM),X-Ray Diffraction and High Resolution Transmission Electronic Microscopy(HRTEM).It was found that the sensor show sensitive response to the introduction of CO of 1.25 mg/Lat 200℃ with a sensitivity factor(S) of 18.It would be desirable that even better sensitivity be achieved by means of enhancement of the ZnOcrystalline structure and improvement of the surface reaction efficiency.More importantly,this is a simple cheap approach to manufacture gas sensors with nice environment-friendly.It would probably turn out to be an economic way to produce gas sensors in a large scale with low cost to meet the industrial requirements.