二氧化锡中空微球用于快速灵敏检测硫化氢

摘要

以氨基酚醛树脂球作模板,通过一种简单的模板法制备了具有中空微球(HMS)结构的二氧化锡;将其涂覆于氧化铝陶瓷管金电极表面,制得一种新型薄膜式硫化氢传感器.采用X射线衍射(XRD)及透射电子显微镜(TEM)表征了材料的微观结构和形貌,并考察了二氧化锡中空微球(SnO2 HMS)的气敏性能.结果表明,二氧化锡中空微球对硫化氢气体表现出良好的气敏特性.在最佳工作温度(200℃)下,所制作的传感器对142.6 mg/m3硫化氢的响应值高达97.13%,响应时间为22 s.该传感器对硫化氢的响应线性范围为0.2852~142.6 mg/m3,相关系数为0.9931,检出限达到0.1549 mg/m3,且几乎不受环境湿度和温度的影响,具有良好的重现性和选择性.对养殖场中硫化氢气体连续监测10个月后,传感器响应信号衰减了5.4%,表明该传感器具有长期稳定的使用寿命,可实现远程监测的实际应用.%Tin dioxide hollow microspheres ( SnO2 HMS ) were prepared using amino-phenol/formaldehyde resin spheres(APF) as templates. A novel thin-film type hydrogen sulfide(H2S) gas sensor was constructed by coating SnO2 HMS onto an alumina ceramic tube based Au electrode. The crystalline phase and microstructure of different nano-materials were characterized by means of X-ray diffraction( XRD) and trans-mission electron microscopy( TEM) , and the gas sensing properties of SnO2 HMS were studied in detail. The experimental results showed that SnO2 HMS had good sensing properties for H2 S. At the optimum operating temperature of 200 ℃, the response signal of the prepared sensor to 142. 6 mg/m3 H2 S was as high as 97. 13%, and the response time was very short, i.e. 22 s. The response linear range to H2S was from 0. 2852 mg/m3 to 142. 6 mg/m3 , with a detection limit of 0. 1549 mg/m3 , and the correlation coefficient was 0. 9931. Almost no effects on the sensor were observed from the environmental humidity and temperature. Also, the sen-sor possessed good reproducibility and selectivity. The sensor response signal reduced by 5. 4%after 10 months of continuous monitoring of H2 S gas in a pig farm, indicating that the sensor has a long-term stable lifetime with valuable application for remote monitoring in practice.