Mixed potential electrochemical NO2 sensor with YSZ ceramic electrolyte for monitoring in online vehicle diagnosis system
Xidong Hao, Yinglin Wang, Pengfei Cheng, Shanfu Sun, Luping Xu, Yintang Yang, Yue Hao
Abstract
For real-time and in-situ NO x monitoring in an online vehicle diagnosis (OBD) system, yttria-stabilized zirconia (YSZ) based high-performance NO 2 mixed potential sensor was successfully fabricated with an MMn 2 O 4 (M = Co, Cd and Zn) sensing electrode(SE). Compared to CdMn 2 O 4 and CoMn 2 O 4 , the ZnMn 2 O 4 sensing electrode had the smallest interface resistance to 100 ppm NO 2 , and the sensor based on ZnMn 2 O 4 -SE exhibited the highest response. To further improve the sensing performance of the device, the effect of the sintering temperature was studied and the sensor based on ZnMn 2 O 4 sintered at 1000 °C has the highest response of 23 mV to 10 ppm NO 2 . Moreover, the present NO 2 sensor has a wide detection range of 1–1000 ppm, with sensitivities of 18 mV/decade for 1–10 ppm NO 2 and 64 mV/decade for 10–1000 ppm NO 2 . In addition, the device also performs excellent repeatability , terrific selectivity, acceptable O 2 resistance and marvelous long-term stability during continuous measurements over 10 days. Overall, based on its excellent sensing performance, the developed sensor has marvelous application prospects for in-situ NO x monitoring in online vehicle diagnosis (OBD) systems.