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The development of high-performance, portable and miniaturized gas sensors has aroused increasing interest in the fields of environmental monitoring, security, medical diagnosis, and agriculture. Among different detection tools, metal oxide semiconductor (MOS)-based chemiresistive gas sensors are the most popular choice in commercial applications and have the advantages of high stability, low cost, and high sensitivity. One of the most important ways to further enhance the sensor performance is to construct MOS-based nanoscale heterojunctions (heteronanostructural MOSs) from MOS nanomaterials. However, the sensing mechanism of heteronanostructural MOS-based sensors is different from that of single MOS-based gas sensors in that it is fairly complex. The performance of the sensors is influenced by various parameters, including the physical and chemical properties of the sensing materials (., grain size, density of defects, and oxygen vacancies of materials), working temperatures, and device structures. This review introduces several concepts in the design of high-performance gas sensors by analyzing the sensing mechanism of heteronanostructural MOS-based sensors. In addition, the influence of the geometric device structure determined by the interconnection between the sensing materials and the working electrodes is discussed. To systematically investigate the sensing behavior of the sensor, the general sensing mechanism of three typical types of geometric device structures based on different heteronanostructural materials are introduced and discussed in this review. This review will provide guidelines for readers studying the sensing mechanism of gas sensors and designing high-performance gas sensors in the future.
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http://dx.doi.org/10.1038/s41378-022-00410-1 | DOI Listing |
Nano Lett
September 2025
School of Materials and Chemistry, University of Shanghai for Science & Technology, Shanghai 200093, China.
Developing low-temperature gas sensors for parts per billion-level acetone detection in breath analysis remains challenging for non-invasive diabetes monitoring. We implement dual-defect engineering via one-pot synthesis of Al-doped WO nanorod arrays, establishing a W-O-Al catalytic mechanism. Al doping induces lattice strain to boost oxygen vacancy density by 31.
View Article and Find Full Text PDFAnal Chem
September 2025
National Key Laboratory of Laser Spatial Information, Harbin Institute of Technology, Harbin 150001, China.
In this paper, a single-quartz-enhanced photoacoustic-photothermal dual spectroscopy sensor based on a spherical acoustic resonator (SAR) is reported for the first time. The dual spectroscopy of quartz-enhanced photoacoustic spectroscopy (QEPAS) and quartz-enhanced photothermal spectroscopy (QEPTS), utilizing a single quartz tuning fork (QTF), eliminates the frequency mismatch issue that occurs when multiple QTFs are used. The dual spectroscopy model was constructed using the finite element method, which provides numerical simulation support for subsequent experiments.
View Article and Find Full Text PDFACS Sens
September 2025
School of Electronic Information, Northwest University, Xi'an 710127, China.
High-sensitivity, multiparameter sensing is increasingly critical for environmental monitoring and electronics. Existing sensing platforms struggle to integrate precise, rapid, and stable monitoring of parts per billion-level hazardous gases and temperature within a single miniaturized device. This study developed a novel sensor based on two-dimensional (2D) indium selenide (InSe), complemented by first-principles density functional theory calculations elucidating the layer-dependent NO adsorption mechanism.
View Article and Find Full Text PDFDalton Trans
September 2025
School of Electronics and Information Engineering, Hebei University of Technology, Tianjin Key Laboratory of Electronic Materials and Devices, 5340 Xiping Road, Beichen District, Tianjin, 300401, China.
Layered double hydroxides (LDHs) have attracted considerable attention in gas sensing applications due to their highly tunable chemical composition and unique two-dimensional layered architecture. In this study, a series of ZnAl-LDHs with varying Zn/Al molar ratios were synthesized a facile hydrothermal method, and their ethanol sensing performance at room temperature was systematically evaluated. The influence of composition on the structural, morphological, and electronic properties of the materials was thoroughly investigated using a suite of characterization techniques, including XRD, FTIR, SEM, TEM, BET, XPS, PL, and EPR.
View Article and Find Full Text PDFNanoscale
September 2025
School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Uttar Pradesh 221005, India.
Early-stage cancer diagnosis is considered a grand challenge, and even though advanced analytical assays have been established through molecular biology techniques, there are still clinical limitations. For example, low concentration of target biomarkers at early stages of cancer, background values from the healthy cells, individual variation, and factors like DNA mutations, remain the limiting factor in early cancer detection. Volatile organic compound (VOC) biomarkers in exhaled breath are produced during cancer cell metabolism, and therefore may present a promising way to diagnose cancer at the early stage since they can be detected both rapidly and non-invasively.
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