Sub‐ppm sulfur dioxide detection using MoS₂ modified multi‐wall carbon nanotubes at room temperature

Abstract

Sulfur dioxide (SO2) is highly toxic to environment and has an adverse effect on a living being. In this report, a chemiresistive SO2 gas sensor based on carboxylic‐acid functionalized multiwalled carbon nanotubes/molybdenum disulfide nanocomposite sensing film is reported. The receptor film was characterized with various morphological, microstructural, and compositional tools such as transmission electron microscope, X‐ray diffraction, and X‐ray photoelectron spectroscopy, respectively. The systematic investigation of gas sensing with this film suggests its selectivity towards SO2 gas with an absolute response of 0.22‐1.81% in the concentration range of 500ppb–3 ppm. The room temperature operation of the device at a low biasing voltage (i.e., 100 mV) makes the device energy efficient. Response and recovery time of the device were found to be of the order of tens of seconds without applying any external stimuli. A plausible sensing mechanism is proposed based on active sites present in the nanocomposite is also proposed.

Indium-doping-induced selenium vacancy engineering of layered tin diselenide for improving room-temperature sulfur dioxide gas sensing

“…With a reaction of 1.81% at a concentration of 3 ppm, the test indicates its selectivity to SO 2 . 19 From the foregoing research studies, it can be concluded that LMD materials exhibit room-temperature SO 2 sensing ascendency. However, because there are few surface defect states and it is difficult to exchange electrons with gas, relatively high detection concentrations and low responsiveness can occur, making it difficult to satisfy the aforementioned industry criteria requirements.…”

Gases in Food Production and Monitoring: Recent Advances in Target Chemiresistive Gas Sensors

“…4 FeO 3 displayed the best gas sensing performance, with a sensor response of 7.6 at an SO 2 concentration of 3 ppm at a low working temperature of 120 • C. The thin film was made using the DC-sputtering technique. The sensor showed a preferential selectivity for the detection of SO 2 gas under the operating condition compared to CH 4 , CO 2 , and CO. An MWCNT/MoS 2 nanocomposite prepared via a simple chemical method was proposed as a low-energy and RT operating sensor layer [88]. The device is selective towards SO 2 gas.…”

Development of MoS2 doping strategy for ehanced SO2 detection at room temperature

“…Air contamination with this gas is one of the causes of many respiratory (laryngitis, chronic bronchitis, respiratory tract infections), and cardiovascular diseases [14,15]. Exposure of a human organism to a concentration of SO 2 equal to 100 ppm is related to a direct threat to life [16][17][18]. The maximum exposure can not exceed 175 ppb per 10 minutes and 2 ppm per 10-hour time period according to air quality standards [17].…”

“…However, their sensitivity toward other gas molecules (including SO 2 ) was reported low in comparison. The response of TMD sheets toward selected analytes can be enhanced via substitutional doping [39][40][41][42][43][44][45][46][47][48], or decoration of their surfaces with single atoms [49], nanoparticles [50,51], and nanotubes [18]. Doping can be an effective strategy to tune the sensitiv-ity of MoS 2 sheets to a relatively wide range of gases, e.g.…”