【作者】 马兴法；

【导师】 汪茫；

【作者基本信息】 浙江大学 ， 材料物理与化学， 2005， 博士

【摘要】 气敏材料与传感器已广泛用于电子鼻、电子舌等仿生系统的设计。在食品工业、环保检测、反恐、防恐、毒品检测、人类、动物一些疾病的早期预测和适时在线监控等方面具有重要的应用价值。研究高灵敏度、快速响应、重现性良好和室温可逆的有机薄膜传感器。同时,通过材料-工艺-器件性能的相关性研究,探讨有机膜的气敏规律性,用于指导新材料的设计和开发。对该领域的深入研究开发和材料与器件的推广应用具有重要的意义。 本文概述了有机气敏材料的研究进展,分析了影响气敏性的主要因素及改进措施。针对这些问题,从敏感材料和制备工艺入手,探讨了如何改善这些性能的有效途径。 研究了酞菁薄膜-非氧化性气体这一弱相互作用体系,比较了全氟代酞菁化合物对室温气敏性的影响。结果表明,氟取代明显改善了ZnPc对系列还原性气体(氨、三甲基胺、甲基胺和三乙基胺)的敏感性和选择性,对部分气体大幅度提高了其响应速度和灵敏度。其灵敏度可提高2-3个数量级。对卟啉类化合物及其全氟代衍生物电响应敏感性的考察结果表明,氟代显著改善了卟啉锌对氨的敏感性,响应速度提高了30倍以上。 为进一步提高有机薄膜的灵敏度和响应速度,对导电性聚合物进行了相应研究。基于导电聚合物的电导强烈依赖于掺杂和去掺杂,采用原位制备、自掺杂等方式,获得了快速响应、高灵敏的有机薄膜。其灵敏度和响应速度远远高于采用传统的旋涂方式获得的相应薄膜,其灵敏度提高了3-4个数量级。为进一步完善旋涂工艺,通过添加少量聚电解质诱导的方式,在保持较高敏感性和快速响应的前提下,改善了其成膜工艺。 通过添加少量的三氟化硼乙醚,利用分子间的相互作用降低噻吩的更多还原

【Abstract】 Gas-sensitive materials and sensors have been widely used in the designs of electronic nose and tongue of bionic systems, and have many potential applications in food industry, environmental monitoring, and counter terror, inspection of drugs and toxic gases, and prognoses of some diseases. To study an organic film sensor with high sensitivity, rapid response and good reproducibility, and attempt to explore some rules to conduct the design and development of new materials by the research of relationship among materials, technologies and properties of devices, it would be very important for investigations in-depth and accelerating applications in these fields.The progresses of organic gas-sensitive materials were reviewed in this paper, and the affecting factors and improving approaches to gas-sensitivity were also analyzed. Being aimed at the sensitivity, response rate, reproducibility and reversibility at room temperature, how to improve these properties were discussed from sensitive materials and film-forming technologies.The gas-sensitivities of weak interaction systems between phthalocyanine film and absorbed gases were studied in this paper, good results on recovery at room temperature were obtained. The gas-sensitivities of zinc phthalocyanine (ZnPc) and its fluorinated derivative (zinchexadecafluorophthalocyanine-ZnF16Pc) films to a series of reducing gases at room temperature are investigated. The results indicate that the gas-sensitivities and the response rates of ZnPc film to ammonia, trimethylamine and methylamine can be improved significantly via fluorination, the gas-sensitivity values to some vapors were increased 2-3 orders, and the fluorination film has a good selectivity and stability, and it can be completely recovered by high-purity N2 at room temperature. The results of examination on the gas-sensitivities of zinc tetraphenylporphyrin evaporation film and zinc-meso-tetra (2,3,4,5,6-pentafluorophenyl)-porphyrin film to a series of organic volatiles under similar conditions show that the sensitivity of zinc porphyrin film to ammonia can also be improved greatly via fluorination, the response speed was enhanced over 30 folds.In order to enhance the sensitivities and response rates of organic films greatly, the gas-sensitivities of conductive polymers and their composite films were studied. Basing on the conductivity of polymer strongly depending on the doping and undoping, several organic films with high sensitivity and rapid response were obtained via in-situ polymerization approach and self-dopingmethod. The values of gas-sensitivity and response rate are much higher than that of poly(aniline) film obtained via conventional spin-coating (polyaniline was dissolved in N-methylpyrrolidone). The gas-sensitivity value was increased 3-4 orders. To improve the film-forming further, the film-forming technology was improved greatly by adding a small amount of poly (sodium-p-styrenesulfonate) under holding high sensitivity.Polythiophene composite film on the interdigital electrodes of carbon was formed with an in-situ polymerization approach at room temperature by adding a small amount of boron trifluoride etherate, which purpose is decreasing the oxidation potential utilizing interaction between molecules. The results indicated that this film showed a good sensitivity to ammonia, and had also a good selectivity to analogy gases and a fast response while exhibiting a good reproducibility. The gas-sensitivity value can reach to 3 orders within 250s.To increase the heat stability of organic films, and expect to obtain new kind composite materials with synergetic or complementary behaviors, and be used in electronic or nanoelectronic devices. Considering P-zeolite being one of type materials with regular channels, which has outstanding surface feature, and is widely used in carrier of catalyze. At the same time, it is also good candidates for template of nano-materials preparation, some organic-inorganic hybrid materials were investigated. The results indicated that, in spite of the heat stability of organic films increasing at certain extent, the gas-sensitivities of some composite systems were decreased. However, the gas-sensitivity was enhanced obviously via adjusting the ratio of Si/Al in zeolite, organic-inorganic hybrid materials with synergetic or complementary behaviors was obtained.Some conductive polymers with nano-structure were obtained via several simple methods, such as: template method, non-template approach and nano-fiber seeding method. Their gas-sensitivities were also examined, and preliminary discussions on dependences among materials, technology, structure and their properties to obtain some valuable information. Comparing to that of conventional polyaniline film via organic solution spin-coating, the value of gas-sensitivity and response rate of the film with nano-wire structure obtained by non-template approach were increased dramatically. Its gas-sensitivity value was increased 3-4 orders.更多还原