High-Response Dual-Purpose No2 Sensor With Layered-Bi2wo6 Sensing Electrode

In this work, we successfully synthesized Bi2WO6 via hydrothermal method. Then, we fabricated a mixed potential-type yttria-stabilized zirconia (YSZ)-based NO2 sensor, incorporating this material. Layered-Bi2WO6 exhibits excellent performance for NO2 detection at 550 degrees C. We found that the working curve of the sensor is divided into two sections. Sensor sensitivities are 13.4 and 65.83 mV/decade in the range of 1-4 and 6-50 ppm NO2 concentration, respectively, indicating that the sensor has the prospect of a dual-purpose sensor to detect NO2 in air and automobile exhaust. The sensor also has good selectivity, stability, and repeatability. The layered structure of Bi2WO6, which significantly increases the threephase boundary area and provides more active sites for the adsorption of NO2, plays a paramount role in enhancing the sensing performance. We discuss the associated sensing mechanism in detail. (C) 2021 Elsevier B.V. All rights reserved.