A special gas sensor based on mesoporous WO3 sensing electrode in medium low temperature for NO2 detection

•Excellent NO2 sensitivity (99.78 mV/decade) and high selectivity were obtained.•The sensor by GDC solid electrolyte followed the mixed-potential mechanism.•Good sensitivity and selectivity were attributed the mesoporous WO3 SE. Herein, a NO2 sensor based on mesoporous WO3 (M−WO3) sensing electrode and Ce0.8Gd0.2O1.9 (GDC) has been fabricated. This device shows high sensitivity in the range of 30–500 ppm NO2 concentration. at different temperatures. Meanwhile, the sensor response value (V) reached 99.78 mV/decade for NO2 detection at 250 °C. Moreover, a high NO2 selectivity, prominent repeatability and stability have been proved for this sensor. The optimization of mesoporous structure for sensing performance has also been discussed.