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

ABSTRACT: NO_x is a notorious emission from motor vehicles and chemical factories as the precursor of acid rain and photochemical smog. Although zirconia-based NO_x 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 NO_x detector or sensor. Herein, a novel amperometric solid-state NO_x sensor was developed using perovskite-type oxide Gd_1-xCa_xAlO_3-δ(GCA) as the electrolyte and NiO as the sensing electrode. NO_x 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 NO_x 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 μA. 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 NO_x sensing showed the potential application of the sensor in motor vehicles.

SUBMITTER: Xiao Y 

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

REPOSITORIES: biostudies-literature