摘要
Ag-WO_3纳米复合材料通过低温溶胶凝胶法(sol-gel)和共渍法成功合成,并且基于该纳米复合材料制备了检测低浓度NO_2气体的旁热式气敏元件。研究了100~300℃的温度范围内该传感器对H_2S、CO、NO_2、C_2H_5OH、CH_3COCH_3的气敏性能。结果表明,质量分数为1.0%Ag-WO_3气敏传感器对10 ppm的NO_2气体展现了最高的灵敏度和选择性。同时对Ag-WO_3气敏传感器探测气体前后的气敏机理进行了讨论和分析。
The Ag-WO_3 nanocomposites were successfully synthesized by the low-temperature sol-gel method and the impregnating method.Meanwhile,the heater-type gas sensors were made to detect NO_2 in the low concentration range.The gas sensing performance of sensors were studied towards H_2S,CO,NO_2,C_2H_5OH and CH_3COCH_3 gases at 100 ℃ to 300 ℃.The experiment results demonstrated that,1.0% Ag-WO_3 sensor was maximally sensitive and selective towards 10 ppm NO_2 gas.At the same time,the mechanism of Ag-WO_3 gas sensor before and after gas detection was discussed and analyzed.
引文
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