文档介绍：摘 要
现代社会安全问题日益突出,对可靠性气体检测要求越来越高。生物、化工、医学和食品行业对具有高灵敏度、稳定性、选择性以及便携性等特征的乙醇气体传感器产生了日益迫切的需求,半导体氧化物纳米线基气体传感器在对环境保护和人体健康方面彰显了巨大的发展潜力和应用空间。本论文研究了超分散 V2O5 纳米线纳米棒以及 V2O5 多级纳米网络结构的种子层诱导原位制备并评价了其对乙醇气体的敏感性能。
在镀有叉指 Pt 电极的氧化铝基底上采用种子层诱导原位水热合成了 V2O5
多级纳米网络结构,实现了材料生长和传感器件组装的一步完成。通过控制不同偏钒酸铵反应物浓度,发现在氧化铝基底上分别形成了多孔纳米花状和纳米蜂巢状的 V2O5 多级纳米网络结构,尤其是多孔花状纳米结构由极细的纳米针和纳米
线自组装构成,并由无序重叠的纳米线、纳米带紧密联系形成网络结构,呈现出一种多孔疏松状的连续网状特征。
V2O5 多级纳米网络结构气敏元件对乙醇气体表现出双工作温度特性,在室
温(20℃)和 250℃下对乙醇气体均显示出了高的灵敏度,好的选择性和快速的响应恢复特性。在该双工作温度下,V2O5 多级纳米花型网络传感器可分别实现对浓度低至 25ppm 和 5ppm 的稀薄乙醇气体的高灵敏探测。随着工作温度的升高,
V2O5 纳米网络结构的导电类型由室温下的 p 型导电特征逐渐转变为 n 型导电特征。分析并探讨了其室温反常 p 型电导和升温导致的 p-n 导电转型的物理机理。
以 P123 作为模板导向剂,采用简单热蒸发生长方法,在空气中热处理氧化铝基片上的偏钒酸铵前驱层合成了具有超分散特征的 V2O5 纳米线、纳米棒结构,
其中单根纳米线的直径大约为 50-100nm,长度约为 10-20μm。纳米线/棒的超分
散特性为单根线/棒的移植和基于单根纳米线/棒的纳米器件的构筑提供了更大的便利和可能性。
关键词:氧化钒;气敏传感器;纳米网络结构;纳米线
ABSTRACT
With the development of modern society, security issues have e increasingly prominent, and the requirements of reliability gas detection are also increasing, Ethanol gas sensors with high sensitivity, stability, selectivity, and portability are used in the biological, chemical, medical and food industries. Gas sensor based on the semiconductor oxide nanowires has great potential applications with the environment and our health. In this article, the ultra-dispersed V2O5 nanowires and nanorods were studied, and gas sensors based on V2O5 hierarchical nanostructured were be able to evaluate the ethanol gas sensing properties.
Gas sensors based on V2O5 hierarchical works were formed through a direct seed-induced hydrothermal growth of nanostructured V2O5 on the substrate attached a pair of patterned Pt electrodes by controlling precursor (NH4VO3) concentrations, Porous flower- or b-like V2O5 hierarchical nanostructures are synthesized on the substrate, especially the flower-work with radially oriented ultrathin nanoneedles and nanoribbons and the overlaped nanowires as constituents, show the continuous works of porous feature.
The ethanol gas