【作者】 姚爽；

【导师】 龚剑；

【作者基本信息】 东北师范大学 ， 无机化学， 2008， 硕士

【摘要】 本文主要以气体传感器测试系统及半导体气敏材料为研究对象,在传统方法的基础上根据实际需要对系统进行了适当的改进以使其具有更加广泛的使用范围,同时将计算机技术与测试系统结合,实现了气敏测试的数字化与图像化。根据气体测试对象的特点制备了两种半导体气敏材料并对其进行了表征和气敏性研究。1.设计和制作了一套气敏测试系统,此系统以传统的旁热式气敏元件为基础,同时可以用于对高分子半导体气敏材料的常温测试。系统操作方法简单易学,有利于气敏性测试在实验室的普及。2.介绍了实验室气敏测试系统的具体使用方法,包括气敏元件制作,系统调试和测试等。通过对数据的拟合和转换,将得到的负载电阻电压合理的转换成气敏元件电阻,从而为表达材料灵敏度提供了更多的可靠数据。3.以海胆状MnO₂为模板用固相法合成了聚苯胺/MnO₂复合材料,用红外光谱、X-射线粉末衍射（XRD）对其进行了表征。复合材料为直径5-6微米的球形,表面粗糙,覆盖着大量的纳米纤维。气敏性测试表明,此复合材料与固相法制备的纯聚苯胺相比灵敏度上升4-5倍。4.通过硝酸纤维素的辅助作用,在水热体系中制备了三维花朵状Ni（OH）₂以此为前驱体得到了三维花朵状NiO。对比实验显示,硝酸纤维素对三维花状结构的形成起着至关重要的作用。气敏性测试显示,三维花朵状NiO制备的气敏元件最佳工作状态是加热电流为1000mA时,材料对甲醛有较好的响应速度。更多还原

【Abstract】 In this article, we focus on the assembly of testing system of gas-sensor and researches of semiconductor gas-sensing materials. According to the actual requirement, some change has been made on the basis of the traditional system to enlarge the testing range. Meanwhile, computer technology and testing system have been integrated, which is propitious to the numeralization and the picturelization of the gas-sensing test. Furthermore, we have synthesized two kinds of semiconductor gas-sensing materials according to the testing system. The gas-sensing property of the materials has been characterized by the self-maded testing system.1. A testing system of gas-sensor has been designed and manufactured which is made on the basis of traditional indirect-heat gas sensor. The testing system can be also used by the macromolecule gas-sensing materials at normal temperature.2. The operating method of the lab-used gas-sensing testing system has been introduced, including facture of gas sensor, debugging and testing. In addition, the export voltage has been transform to resistance through the simulation and transformation of relative data, which offers more reliable data to express the sensitivity.3. PANI/MnO₂ complex material has been successfully prepared by using urchin-like MnO₂ as a single template through solid state method. The structure and morphology of the complex material were characterized by IR spectrum, XRD pattern, and SEM images. The diameter of the product with sphere-like structure was from 5 to 6μm. The surface of the spheres was coarse covered with large amount of nanofibers. The sensitivity to NH₃ has been increased by 4-5 times compared with other PANI material4. Pyroxylin were used as assistant agent to synthesize flower-likeβ-Ni（OH）₂ through hydrothermal process. Then NiO crystal could be obtained through thermal decomposition of the flower-likeβ-Ni（OH）₂. Meanwhile, The flower-like morphology could be preserved during the thermal decomposition process. Series of experiments indicated that pyroxylin played a key role in the formation of the flower-likeβ-Ni（OH）₂ structure. Gas sensing test indicated that flower-like NiO is in the best working state with the heating current 1000 mA, and had a better performance when exposed to formal dehyde.更多还原