A GdAlO3 Perovskite Oxide Electrolyte-Based NOx Solid-State Sensor.

ABSTRACT: NOx is a notorious emission from motor vehicles and chemical factories as the precursor of acid rain and photochemical smog. Although zirconia-based NOx sensors have been developed and showed high sensitivity and selectivity at a high temperature of above 800?°C, they fail to show good performance, and even don't work at the typical work temperature window of the automotive engine (<500?°C). It still is a formidable challenge for development of mild-temperature NOx detector or sensor. Herein, a novel amperometric solid-state NOx sensor was developed using perovskite-type oxide Gd1-xCaxAlO3-?(GCA) as the electrolyte and NiO as the sensing electrode. NOx sensing properties of the device were investigated at the temperature region of 400-500?°C. The response current value at -300?mV was almost linearly proportional to the NOx concentration between 300 and 500?ppm at 500?°C. At such a temperature, the optimal sensor gave the highest NO2 sensitivity of 20.15?nA/ppm, and the maximum response current value reached 5.57??A. Furthermore, a 90% response and 90% recover time to 500?ppm NO2 were about 119 and 92?s, respectively. The excellent selectivity and stability towards NOx sensing showed the potential application of the sensor in motor vehicles.

SUBMITTER: Xiao Y 

PROVIDER: S-EPMC5122901 | biostudies-other | 2016 Nov

REPOSITORIES: biostudies-other