Exclusive detection of volatile aromatic hydrocarbons using bilayer oxide chemiresistors with catalytic overlayers

Abstract

The accurate detection and identification of volatile aromatic hydrocarbons, which are highly toxic pollutants, are essential for assessing indoor and outdoor air qualities and protecting humans from their sources. However, real-time and on-site monitoring of aromatic hydrocarbons has been limited by insufficient sensor selectivity. Addressing the issue, bilayer oxide chemiresistors are developed using Rh–SnO2 gas-sensing films and catalytic CeO2 overlayers for rapidly and cost-effectively detecting traces of aromatic hydrocarbons in a highly discriminative and quantitative manner, even in gas mixtures. The sensing mechanism underlying the exceptional performance of bilayer sensor is systematically elucidated in relation to oxidative filtering of interferants by the CeO2 overlayer. Moreover, CeO2-induced selective detection is validated using SnO2, Pt–SnO2, Au–SnO2, In2O3, Rh–In2O3, Au–In2O3, WO3, and ZnO sensors. Furthermore, sensor arrays are employed to enable pattern recognition capable of discriminating between aromatic gases and non-aromatic interferants and quantifying volatile aromatic hydrocarbon classifications.

Enhanced sensing performance of armchair stanene nanoribbons for lung cancer early detection using an electric field

“…As a result of industrial developments, the need for environmental gas monitoring has grown. In recent years, gas sensors have become more vital for many applications such as the detection of harmful and industrial gases, [1][2][3][4] military applications, 5 and disease diagnostics. [6][7][8] The analysis of exhaled breath biomarkers for disease diagnosis is one of the most recent applications of gas sensors.…”

“…A number of theoretical and experimental investigations have been carried out on stanene to explore its application as topological insulators 24 and sensors. [21][22][23] Because of its buckling structure and also its hybridization, which is a mixture of sp 2 and sp 3 , it is a promising alternative for graphenebased materials in sensing applications. Furthermore, Sn atoms are heavier than carbon atoms in graphene, which causes the intrinsic spin-orbit coupling effect (SOC) and opens a band gap of 0.1-0.44 eV.…”

Behind the gas sensors: revealing sensing mechanisms with advanced magnetic resonance technology

“…CO 2 , H 2 O, and N 2 ) and oxidizing gases, giving potential for various gas sensing techniques. 35 These properties of chemical structures are easily characterized by EPR spectroscopy, compared to XPS or other methods which suffer from low sensitivity and limitations in detection depth. Therefore, extensive research has been conducted on the surface defects of numerous metal oxides, perovskites, and single atom doped sensing materials using EPR.…”

In situ construction of AFe2O4/Fe2O3 (A = Cd, Ca, Zn) array structures for selective detection of VOCs

“…6,7 However, it is difficult to detect mixed VOC gases based on pure MOS gas sensors. 8 Consequently, the development of integrated gas sensors will enable the selective detection of mixed VOC gases, 9–11 which will be more relevant for the application of sensors in real environments.…”