Rapidly detecting the carcinogen acetaldehyde: preparation and application of a flower-like MoS2 cataluminescence sensor at low working temperature

Abstract

In this paper, a cataluminescence (CTL) gas sensor based on flower-like molybdenum disulfide (MoS₂) is developed. The experimental results show that it has high sensitivity and selectivity to acetaldehyde. The CTL sensor has the advantage of fast response; the response time is about 3 s and the recovery time is about 40 s. The optimal working temperature of this sensor is 174 °C, which is lower than that of the CTL sensors used for acetaldehyde detection in many other reports. Under the optimized conditions, the CTL signal intensity shows a good linear relationship with acetaldehyde concentration (R² = 0.9991) within the concentration range of 40–2000 ppm, and the detection limit (LOD) is 3.75 ppm. The selectivity experiment results show that the sensor has an obvious response to acetaldehyde and a very weak response to acetic acid, and has no response to many other VOCs (ether, cyclohexane, butyl ether, carbon tetrachloride, ethanol, toluene, formaldehyde, glycerol, trichloromethane and xylene). After 8 repeated measurements for four weeks, the relative standard deviation (RSD) of the CTL sensor is 1.03%, indicating that it has good reproducibility and stability, which shows that the CTL sensor has a promising prospect for the detection of acetaldehyde.