Carbon SH-SAW-Based Electronic Nose to Discriminate and Classify Sub-ppm NO2

Abstract

In this research, a compact electronic nose (e-nose) based on a shear horizontal surface acoustic wave (SH-SAW) sensor array is proposed for the NO2 detection, classification and discrimination among some of the most relevant surrounding toxic chemicals, such as carbon monoxide (CO), ammonia (NH3), benzene (C6H6) and acetone (C3H6O). Carbon-based nanostructured materials (CBNm), such as mesoporous carbon (MC), reduced graphene oxide (rGO), graphene oxide (GO) and polydopamine/reduced graphene oxide (PDA/rGO) are deposited as a sensitive layer with controlled spray and Langmuir–Blodgett techniques. We show the potential of the mass loading and elastic effects of the CBNm to enhance the detection, the classification and the discrimination of NO2 among different gases by using Machine Learning (ML) techniques (e.g., PCA, LDA and KNN). The small dimensions and low cost make this analytical system a promising candidate for the on-site discrimination of sub-ppm NO2.

Controllable-assembled functional monolayers by the Langmuir–Blodgett technique for optoelectronic applications

“…50,139,140 Graphene and its oxide nanosheets are typical 2D materials. Since its discovery in 2004, 141 graphene has been active as a promising material in various fields such as electrochemical storage, 142 sensitive response sensor devices, 143 and optoelectronic devices 144 due to its excellent characteristics such as low cost, high specific surface area, high electrical conductivity, and high transmittance. 141 The chemical vapor deposition (CVD) method is commonly used to produce graphene nanosheets or other 2D materials on specific substrates and arealimited regions, restricting the scope of applications of twodimensional materials.…”

Integrating LoRa-Based Communications into Unmanned Aerial Vehicles for Data Acquisition from Terrestrial Beacons

“…For example, in precision agriculture, it has been used to monitor crops and detect diseases [27,28]. In environmental monitoring, e-noses have been applied to monitor atmospheric pollution [29,30]. Medical applications have also employed e-noses in diagnosing diseases [31].…”

Forecasting the Post-Pandemic Effects of the SARS-CoV-2 Virus Using the Bullwhip Phenomenon Alongside Use of Nanosensors for Disease Containment and Cure

“…A successful presentation of an e-nose device with a sensor array, a data acquisition system, and machine learning that can identify changes of volatile organic compounds (VOC) present in the exhaled breath of patients and healthy beings with a 92.3% accuracy was produced [ 25 ]. For NO 2 detection, classification, and discrimination among some of the most significant ambient toxicants, a miniature electronic nose (e-nose) based on a shear horizontal surface acoustic wave (SH-SAW) sensor array was presented by [ 26 ]. Acquiring real-time breath humidity data is critical for calibrating gas sensors and precisely monitoring a patient’s physiological information for non-invasive and point-of-care diagnostic applications.…”