Abstract Here we prepare a composite of tungsten oxide films/porous silicon (WO3/PS) hybrid structure synthesized by electrochemical deposition of WO3 films onto p-type PS with subsequent annealing process in air. The obtained WO3/PS products were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy (RS). The gas-sensing properties of WO3/PS composite to NO2 ranging from room temperature (RT, ∼25 °C) to 200 °C were studied. The result indicated that all the WO3/PS gas sensors showed typical p-type semiconductor behavior and had an optimal working temperature of RT. Furthermore, compared with PS, the proper deposited WO3/PS composite exhibited a higher gas response, shorter response-recovery time, good repeatability and selectivity toward NO2 gas at RT. This improvement probably owing to the heterojunction effect and its unique microstructure properties. In addition, the possible NO2-sensing mechanisms were also discussed in this paper.

中文翻译：

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在多孔硅上电沉积氧化钨膜，用于室温下的 NO 2 检测

摘要 在这里，我们制备了氧化钨膜/多孔硅 (WO3/PS) 混合结构的复合材料，通过将 WO3 膜电化学沉积到 p 型 PS 上，然后在空气中进行退火工艺合成。通过扫描电子显微镜 (SEM)、X 射线衍射 (XRD) 和拉曼光谱 (RS) 研究获得的 WO3/PS 产物。研究了 WO3/PS 复合材料在室温（RT，~25°C）到 200°C 范围内对 NO2 的气敏特性。结果表明，所有的 WO3/PS 气体传感器都表现出典型的 p 型半导体行为，并具有最佳工作温度 RT。此外，与 PS 相比，适当沉积的 WO3/PS 复合材料在室温下表现出更高的气体响应、更短的响应-恢复时间、良好的重复性和对 NO2 气体的选择性。这种改进可能是由于异质结效应及其独特的微观结构特性。此外，本文还讨论了可能的 NO2 传感机制。