Basic study on the development of high performance gas-sensing system based on the holographic method.

本研究的目的是，通过理论和实验的方法，在高性能的气体传感系统的发展，使用全息光栅的方法。主要研究内容如下：1.全息图的制备及其表征通过在真空蒸镀的Au薄膜、SnO_2和ITO涂层的玻璃基底上曝光光致抗蚀剂，用两束紫外激光干涉，制备了全息图。暴露、冲洗，2.金基全息图上巯基自组装（SA）的原位监测研究了亚甲基蓝在Au-和ITO-上的电极反应初步结果的全息图表明，在衬底表面的介电性能的变化是可能的监测本方法。因此，该方法被应用于研究巯基在金全息图上的SA过程，该过程预计将在没有颜色变化的情况下进行。首次从实验上获得了SA结晶的动力学参数。3.金属氧化物全息图对可燃气体的响应研究了SnO 2基全息图对H2和CO的响应，观察到了对模型气体的响应，但发现响应与温度有一定的关系。研究了影响时间响应和气体选择性的因素。混合基板被建议是有用的全息图的基础材料，用于选择性地检测感兴趣的气体。4.原位监测的光催化反应的TiO 2全息图由于本方法被证明是高度敏感的表面光学常数的微小变化，它也被应用到研究的光诱导的表面反应的TiO 2基全息图。实验证明，监测亚单层吸附的中间体，在现场期间获得的。

The present research has aimed, by both theoretical and experimental approaches, at the development of a high performance gas-sensing system using a holographic grating method. Those major issues studied are as follows :1.Preparation of holograms and their characterizationHolograms were prepared on vacuum-evaporated Au thin films, SnO2 and ITO coated glass substrates by exposing the overcoated photoresist to the interfering two UV-laser beams. Exposure, rinsing, optical geometry and other conditions were optimized to give holograms of higher diffraction and higher exposure of the bare substrate as sensing material.2.In situ monitoring of thiol self-asembly (SA) on Au-based hologramsPreliminary results on the electrode reaction of methylene bule using Au- and ITO-based holograms showed that the change in dielectric properties of the substrate surface are possibly monitored by the present method. Thus, the method was applied to study SA process of thiol on Au-hologram which is expected to proceed with no color change to be monitored. The kinetic parameters of SA crystalization was experimentally obtained for the first time.3.Holographic response to flammable gas by metal-oxide semiconductorsSnO2-based hologram was tested as sensor to H2 and CO.The response to the model gas was observed but found to be somewhat temperature dependent. Factors affecting the time response and the gas selectivity were also studied. Hybrid substrate was suggested to be useful as hologram base material for the selective detection of the gas of interest.4.In situ monitoring of the photocatalytic reaction on a TiO2 hologramSince the present method was shown to be highly sensitive to the small change in the surface optical constant it was also applied to the study of a photoinduced surface reaction of photocatalysis using TiO2-based hologram. The experimental proof of monitoring submonolayr adsorbed intermediates was obtained in situ during the photocatalysis.