Sensors and Sensor Networks: Design, Synthesis and Performance Evaluation of Nanocomposite Semiconductor Gas Sensors

拟议研究计划的主要目标是成功证明使用一种新的合成方法制造的纳米复合材料SnO2传感器的性能显著提高。纳米颗粒的分段成核将用于在多元扩散燃烧器上制备掺杂贵金属添加剂的高附加值SnO2传感器材料。特别是，由于金的催化活性极高，先前的研究表明，金纳米岛有望显著提高传感器的灵敏度。因此，Au/SnO2体系将成为研究的重点。颗粒大小、Au负载量和相对颗粒形貌对传感器性能的影响将被定量地确定。将使用高分辨率显微镜成像(例如，结合元素分析方法的扫描和透射电子显微镜)来表征材料的特性。这些粉末在气体传感器应用中的性能将通过传感器的时间响应、灵敏度、选择性和稳定性来量化。这项研究的成果包括有可能创造出机械简单、快速响应、灵敏、选择性、稳定的有毒气体传感器，这些传感器可以在很大的温度范围内运行。由于在内燃机系统中的应用，具有这些特性的NOx传感器是该研究计划的具体重点。因此，更广泛的影响包括更精确地设计汽车尾气催化剂和相应的材料，并节省成本。

The primary objective of the proposed research program is to successfully demonstrate dramatically improved performance of nanocomposite SnO2 sensors made using a novel synthesis approach. Staged nucleation of nanoparticles will be used to make high-value-added SnO2 sensor materials doped with noble metal additives using a multi-element diffusion burner. In particular, gold nano-islands are expected to yield remarkable increases in sensor sensitivity due to the extremely high catalytic activity of Au demonstrated in previous studies. Therefore, the Au/SnO2 system will be the primary focus of the research effort. The effects of particle size, Au loading and relative particle morphologies on sensor performance will be quantitatively determined. High-resolution microscope imaging (e.g. scanning and transmission electron microscopy coupled with elemental analysis methods) will be used to characterize the materials properties. Performance of the powders in gas sensor applications will be quantified in terms of sensor time response, sensitivity, selectivity and stability. Outcomes of the research include the potential to create mechanically simple, rapid time response, sensitive, selective, stable, toxic-gas sensors that can be operated over a large temperature range. NOx sensors with these properties are a specific focus of the research program due to applications in internal combustion engine systems. The broader impacts therefore include more precise design of automotive exhaust gas catalysts and corresponding materials and costs savings.