快速吸附与脱附的声表面波H_2S传感器  

Fast absorption and desorption H_2S sensors based on surface acoustic waves

作　　者：王秀东[1] 李红浪[1] 付琛[1] 梁勇[1] 何世堂[1] 

机构地区：[1]中国科学院声学研究所,北京100190

出　　处：《应用声学》2011年第3期213-219,共7页Journal of Applied Acoustics

基　　金：国家自然科学基金资助项目(61071054)

摘　　要：本文主要研究了基于SnO_2/CuO薄膜的声表面波(SAW)传感器(室温下,工作频率约为147.8 MHz)检测H_2S气体的特性。以36°YXLiTaO_3为基片制作声表面波器件,通过采用射频磁控溅射法在其表面淀积SnO_2/CuO的复合薄膜制作出H_2S气体传感器。由场发射电子扫描电镜观察薄膜,薄膜连续均匀且表面分布大量微气孔,因而具有良好的吸附性。然后本文在85℃～205℃范围内对传感器的吸附和脱附速率、灵敏度及选择性等进行了实验研究。实验结果表明,所制备的传感器在较低温度下同时具备快速吸附和脱附特性,工作在190℃时气体吸附和脱附速率最快,检测20ppm H_2S的响应和恢复时间分别为30s、15s;工作在160℃时,传感器检测20ppmH_2S的灵敏度最高,工作频率变化约230 kHz,且对于低浓度2 ppm H_2S,频率变化可达45 kHz。同时,传感器也表现出良好的重复性和选择性。A surface acoustic wave （SAW） sensor （operating at about 147.8 MHz at room temperature） based on SnOJCuO composite thin films has been investigated for detecting H2S gas in this paper. The films were deposited onto a 36°YXLiTaO3 SAW device by a RF magnetron sputtering technique. From field emission electron scanning electron microscope image, it can be concluded that the films were continuous, uniform, and porous, exhibiting high absorbability. Then at different operating temperatures varying from 85 ℃ to 205 ℃, the speed of adsorption and desorption, sensitivity, selectivity and other properties of sensing H2S gas were studied by experiments. Our experimental results showed that the prepared sensor possessed fast adsorption and desorption characteristics, operating at relatively low temperature. For detecting 20ppm H2S, the shortest response and recovery time of 30s and 15 s respectively were obtained at 190℃, and the highest sensitivity of about 230kHz frequency shift wasobserved at 160℃. Moreover, 45 kHz response can be seen for detecting low concentration of 2 ppm H2S. Satisfied repeatability and selectivity were also demonstrated by our experiments.

关 键 词：声表面波 SnO2/CuO H2S 气体传感器 

分 类 号：TQ426[化学工程]