Research on gas-sensing properties of lead sulfide-based sensor for detection of NO2 and NH3 at room temperature

In the present paper, the gas-sensing characteristics of novel gas sensors based on PbS were investigated. The sensors exhibited high responses to NO2 and NH3 at room temperature. No response to other gases was observed. The response magnitude of sensors based on PbS prepared with Na2S at 50 °C was 266.4 to NO2 at operating voltage 5 V. The response and recovery time was about 54 and 43 s, respectively. The response magnitude of PbS prepared with Na2S at 80 °C was about 301 to NH3 at operating voltage 5 V. The response and recovery time was about 46 and 67 s, respectively. The influence of the working temperature and operating voltage on the sensor response was also studied. The sensing mechanism of the sensor was discussed.