MgO掺杂SnO2甲醛传感器的气敏性能

用MgO掺杂SnO₂材料(SnO₂/MgO)研制了旁热式甲醛传感器，采用紫外光激发的方式使传感器能在室温下工作.利用X射线衍射仪、热场发射扫描电镜、比表面积与孔隙率分析仪对SnO₂和SnO₂/MgO材料进行了物相组成、微观形貌的表征和比表面积的测定，并在不同退火温度、不同紫外光照射强度下对传感器进行了性能测试.结果表明:掺杂后的材料比表面积更大、吸附能力更强，当退火温度为650 ℃、紫外光照射强度为1.75 mW/cm2时SnO₂/MgO传感器的灵敏度最好.在以相同体积分数的O₂、C₂H₆O作为干扰气体时，SnO₂/MgO气敏传感器对甲醛具有良好的选择性.研究结果为探索高灵敏的甲醛检测新技术提供了参考.

Gas Sensing Properties of the MgO Doped SnO2 Formaldehyde Sensor

A side-heating formaldehyde sensor (SnO₂/MgO) was fabricated by doping SnO₂ with MgO. The UV light excitation method allowed the sensor to work at room temperature. The phase composition, microstructure and specific surface area of SnO₂ and SnO₂/MgO materials were characterized with the X-ray diffractometer, thermal field emission scanning electron microscopy and specific surface and porosity analyzer, and the performance of the sensor made of SnO₂ and SnO₂/MgO was tested under different annealing temperatures and different UV light irradiation intensities. The results show that the doped material has larger specific surface area and stronger adsorption capacity, and the sensitivity of SnO₂/MgO sensor has the best sensitivity when the annealing temperature is 650 ℃ and the UV light irradiation intensity is 1.75 mW/cm2. When O₂ and C₂H₆O of the same volume fraction are used as the interference gas, it is found that the SnO₂/MgO sensor has good selectivity for HCHO. The research results provide a reference for the exploration of a new highly sensitive formaldehyde detection technology.