复合生物膜气敏传感器及其测试系统研究

Study on Biological Complex Film Gas Sensor and Its Measurement System

为了降低气体传感器功耗、获得高的灵敏度和选择性,利用生物提取液的气敏特性,制作了石英晶体复合生物膜气体传感器。对石英晶体表面进行三种不同的预处理后,表面涂覆数种生物提取液膜,研究了基片预处理方法对传感器敏感度的影响和传感器响应信号的长期稳定性。采用紧凑高效的振荡电路,充分利用数据采集卡资源,构成了灵敏的气体检测系统。新型传感器不需要加热、灵敏度高,响应特性在30天内保持稳定。对8MHz左右的石英晶体气体传感器所采用的频率测量方法准确度为±5Hz。

In order to reduce the power consumption of gas sensor, obtain high sensitivity and excellent selectivity, the biological complex film gas sensor was manufactured using quartz crystal as the substrate that is coated by biological liquid film. Three kinds of pretreatment for the quartz crystal were carried out before the biological liquid films were coated. The influence of pretreatment methods on sensor sensitivity was investigated. The long - term stability of the sensor response signal was studied. The frequency measurement system for the gas sensor was built, which uses compact and efficient circuit and makes full use of the function of data acquisition card. The new gas sensor doesnt require any heating and has high sensitivity; the response signal curve of the new sensor stays stable in 30 days. The frequency measurement accuracy for 8MHz quartz crystal gas sensor is ± 5Hz.