具有高效三相界面的阻抗谱型NO_(2)传感器

Impedancemetric-type NO_(2) sensor with High Efficiency Three-phase Boundary

基于钆掺杂的二氧化铈(CGO)固体电解质和NiO敏感电极(NiO-SE)制备了阻抗谱型NO_(2)传感器,并研究了其的气敏特性。采用浓盐酸刻蚀CGO多孔层骨架,以获得较大的三相界面(TPB)面积,提高传感器的传感性能。采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)分析传感器的相组成和表面形貌。采用CHI660型电化学工作站测试传感器的传感性能。结果表明,浓盐酸刻蚀后,CGO多孔层的表面粗糙度增加。对刻蚀时间(30~180 min)进行了优化,刻蚀120 min时传感器的敏感性能最佳。当温度为500℃时,传感器在0~700 ppm的NO_(2)浓度中灵敏度高达12.95。该传感器对CO_(2)、CH_(4)、H_(2)、NO_(2)、NO具有良好的抗干扰能力,O_(2)对传感器性能具有一定的影响。

The gas sensing properties of the impedancemetric-type NO_(2)sensor based on gadolinia-doped ceria(CGO)solid electrolyte and NiO sensing electrode(NiO-SE)were studied.Concentrated hydrochloric acid was used to etch the porous skeleton of CGO layer to obtain larger three-phase boundary(TPB)area,enhancing the sensing performance of the sensor.The phase composition and surface morphology of the sensor were analyzed by X-ray diffractometer(XRD)and scanning electron microscope(SEM).The performance of the sensor was tested by electrochemical workstation CHI660.The results show that the surface roughness of the sensor increases after etching.The etching time(30~180 min)were optimized,and the results show that the sensor has the best sensitivity when the etching time is 120 min.The sensitivity of sensor is 12.95 with NO_(2)concentrations of 0~700 ppm at 500℃.The sensor has a good anti-jamming ability to CO_(2),CH_(4),H_(2),NO_(2),NO,but O_(2)has some influence on sensing performance of sensor.