Investigation on Amperometric-type NO_2 Sensor Based on Nano CuO Electrode
Nano-size CuO sensing material was prepared by infiltration in the first time.A new type of amperometric NO2 sensor was fabricated using yttria-stabilized zirconia(YSZ) as electrolyte and CuO nanoparticles as sensing electrode.The phase composition and morphology of NO2 sensor were investigated by XRD and SEM,respectively.NO2 sensing properties of the sensor were investigated by IM6e electrochemical workstation.The results showed that the diameter of CuO grain was around 100 nm.The sensor showed preferential sensitivity to NO2.The response current value at-300mV was found to vary almost linearly with the NO2 volume fraction from 0 to 5.0×10-4 at 500-600 ℃.The response and recover time to 90% of level was around 50 s at 400 cm3/min.The response signal of the sensor was so stable during testing time.The sensor was hardly affected by co-exsitant O2 and CO2.