Sekulić Dalibor L, Ivetić Tamara B
Department of Power, Electronic and Telecommunication Engineering, Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovića 6, 21000 Novi Sad, Serbia.
Department of Physics, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia.
Sensors (Basel). 2023 Oct 6;23(19):8261. doi: 10.3390/s23198261.
In this study, we report on the room-temperature characteristics of an impedance-type humidity sensor based on porous tin oxide/titanium oxide (SnO/TiO) composite ceramics modified with Mo and Zn. The SnO/TiO-based composites synthesized in the solid-state processing technique have been structurally characterized using X-ray diffraction, scanning electron microscopy, energy dispersive, and Raman spectroscopy. Structural analysis indicated the desired porous nature of the synthesized ceramics for sensing applications, with an average crystallite size in the nano range and a density of about 80%. The humidity-sensing properties were evaluated within a wide relative humidity range from 15% to 85% at room temperature, and the results showed that a better humidity response had a sample with Mo. This humidity-sensing material exhibits a linear impedance change of about two orders of magnitude at the optimal operating frequency of 10 kHz. Furthermore, fast response (18 s) and recovery (27 s), relatively small hysteresis (2.8%), repeatability, and good long-term stability were also obtained. Finally, the possible humidity-sensing mechanism was discussed in detail using the results of complex impedance analysis.
在本研究中，我们报告了一种基于用钼（Mo）和锌（Zn）改性的多孔氧化锡/氧化钛（SnO/TiO）复合陶瓷的阻抗型湿度传感器的室温特性。采用固态加工技术合成的基于SnO/TiO的复合材料已通过X射线衍射、扫描电子显微镜、能量色散和拉曼光谱进行了结构表征。结构分析表明，合成的陶瓷具有用于传感应用所需的多孔性质，平均微晶尺寸在纳米范围内，密度约为80%。在室温下，在15%至85%的宽相对湿度范围内评估了湿度传感特性，结果表明含Mo的样品具有更好的湿度响应。这种湿度传感材料在10 kHz的最佳工作频率下表现出约两个数量级的线性阻抗变化。此外，还获得了快速响应（18秒）和恢复（27秒）、相对较小的滞后（2.8%）、可重复性和良好的长期稳定性。最后，利用复阻抗分析结果详细讨论了可能的湿度传感机制。
