一种采用穴番-A敏感膜的新型声表面波瓦斯传感器的研究

本文利用笼形超分子材料穴番-A对甲烷分子的特异性包合作用，提出了一种能够在室温下工作的采用穴番-A敏感膜的新型声表面波瓦斯传感器。设计研制了中心频率为300 MHz的低损耗、高Q值SAW谐振器，并以所研制的谐振器构成双通道差分振荡器。分别以点涂法和旋涂法在传感通道SAW谐振器表面进行了敏感膜的镀膜。通过实验观察对比了采用两种镀膜方式的SAW瓦斯传感器在常温下对5%甲烷气体的响应。实验结果显示点涂镀膜的传感器响应约为1 kHz，远大于旋涂镀膜方式。AFM表面形貌表征显示了敏感膜表面粗糙度是造成这一差异的主要原因。实验还研究了传感器对不同浓度甲烷气体的响应，结果表明传感器响应随气体浓度降低而减小，两者存在良好的线性关系，测试灵敏度为205 Hz/%，检测下限约为0.2%。

A Novel Surface Acoustic Wave Methane Sensor Coated with Cryptophane-A

Utilizing the supramolecular compound cryptophane-A’s specific absorption to methane molecules,a novel room-temperature SAW methane sensor covered with cryptophane-A film is proposed. A 300 MHz SAW reso?nator with low insertion loss and high quality factor is designed. Two-channel differential oscillator using SAW reso?nators as feedback elements is fabricated.The film deposition on the SAW resonator is completed by drop-coating and spin-coating method respectively. Experiments have been conducted to study the response to 5% methane of sensors coated via two coating methods. The results show that the response of drop-coated sensors achieves 1 kHz, much larger than spin-coated ones. The surface topography via AFM illustrates that the surface roughness of sensing films is the main cause of the difference. The sensor’s response to various methane concentrations is also studied. The result demonstrates that the sensor’s response and methane concentrationare in approximatelinear relationship. The measured detection sensitivity is 205 Hz/%,and the detection limit is about 0.2%.