【摘要】 为了提高ZnO纳米线的酒敏特性,利用紫光激发经浸渍法获得Ag修饰的ZnO纳米线.利用扫描电子显微镜(SEM),X射线衍射仪(XRD)对修饰后的ZnO纳米线进行了晶体结构和形貌的表征.结果表明其晶体结构中既有六方纤锌矿结构的ZnO,又有面心立方的Ag.三维网络结构的ZnO纳米线的表面被一层致密的具有高孔隙率的Ag颗粒覆盖,使得ZnO纳米线具有更高的比表面积.纯ZnO纳米线和Ag修饰的ZnO纳米线都用作气敏基料,根据它们在酒精蒸气中紫光照射和无紫光照射条件下电阻的变化来测定它们的气敏特性.结果显示紫光照射下经质量分数为6%AgNO3修饰的ZnO纳米线对酒精蒸气的最大灵敏度由75.8提高到175.77.此过程中光催化氧化-还原反应起到了重要作用.更多还原

【Abstract】 To improve the gas sensitivities of ZnO nanowires to alcohol,the Ag-modified ZnO nanowires via immersion method were obtained by violet irradiation.The crystal structure and morphology of Zn0 nanowires were characterized by scanning electron microscope(SEM)and X-ray diffraction(XRD),respectively.The results show that the obtained Ag-modified ZnO nanowires are composed of hexagonal wurtzite ZnO structure and face-centered cubic Ag structure.The three-dimensional network of ZnO nanowires,modified by condensed Ag grains,forms a highly porous structure with a high surface-to-volume ratio.Pure ZnO and Ag-modified ZnO nanowires were tested as the gas-sensing material,whose gas-sensing properties were measured according to changes of their electrical resistance when they were exposed to alcohol with and without violet irradiation.The measurement indicates that the maximum gas sensitivity of ZnO nanowires to alcohol,modified by AgNO3 with mass fraction of 6%,is increased from 75.8 to 175.77.It is believed that the photo-catalytic oxidation-reduction reaction has an important effect on the gas-sensing properties to alcohol.更多还原