NiO/YSZ结构NO传感器的敏感特性

SENSING CHARACTERISTIC OF NO SENSOR WITH NiO/YSZ STRUCTURE

制备以Y2O3稳定的ZrO2(yttria stabilized zirconia,YSZ)为固体电解质、NiO为敏感电极的混合电势型NO传感器。用X射线衍射仪和扫描电镜对该传感器进行理化分析,测量其在不同高温和不同NO体积(下同)浓度的气氛中的响应电势,通过电化学阻抗谱分析法研究该传感器的高温阻抗谱特性。结果显示:在500～750℃,该传感器响应表现为与NO浓度的对数呈明显线性关系的负电势,电势幅值和灵敏度均随工作温度的升高而减小。在600℃,阻抗谱形成的半圆弧随NO浓度的增加呈规律性缩小。

Mixed-potential-type NO sensor based on yttria-stabilized zirconia（YSZ） with NiO sensing electrode was prepared by the screen-printing technique and its physical characteristics were studied by the X-ray diffraction and scanning electron microscope. The response of electromotive force （EMF） and complex impedance of the sensor were tested under different NO concentrations （in volume,the same below） and temperatures. The results show that,at the range of 550–750 ℃,the EMF values are negative and almost linear to the logarithm of NO concentration. But the sensitivity of the sensor and the amplitude of the EMF response to NO concentration both obviously decrease with the increase of the work temperature. In addition,the semicircular arcs of the complex impedance spectra shrink regularly with a raise of NO concentration at 600 ℃.