Highly Selective and ppb-Level Butanone Sensors Based on SnO₂/NiO Heterojunction-Modified ZnO Nanosheets with Electron Polarity Transport Properties

Abstract

Gas sensors require the construction of composites with high reactivity to reduce the detection limit, but this can lead to a broad-spectrum response between the adsorbed oxygen and the target gas, making it difficult to improve selectivity. In this study, the phenomenon of electron polar transport properties of the two-dimensional heterojunction material is first discovered in gas sensing and utilized to greatly improve the selectivity of butanone sensors. Ultra-thin porous ZnO nanosheets modified with SnO 2 / NiO heterogeneous particles are synthesized to achieve 20 ppb detection limits for butanone with a response of 328 to 100 ppm butanone, which is the lowest known detection limit. The combination of reaction kinetics and liquid chromatography−mass spectrometry reveals a good synergistic catalytic effect of SnO 2 /NiO heterogeneous particles, which may contribute to the high response and low detection limit of butanone. Finally, the possible mechanism for the generation of electron polar transport phenomenon is analyzed in the two-dimensional heterojunction material. This work provides a novel perspective for achieving both selectivity and detection limits in gas sensors, with universal applicability and application potential.

Microflowers Composed of VO2 Nanoflakes for Selective Detection of Acetone and Ammonia

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Theoretical Validation of Non-Noble Cu Sites Integrated on SnO2 Nanoflowers for Enhanced Gas Sensing of Ethanethiol at Room Temperature

“…Consequently, detecting its presence in the environment is crucial for protecting human health and reducing safety risks. The detection of volatile reduced sulfur compounds is currently facilitated by three methods, including gas sensors, chemiluminescence analysis, and optical detection technologies. − These techniques are differentiated by their unique contributions to enhanced sensitivity, rapid response times, and the ability to perform simultaneous multicomponent analyses. , Metal-oxide gas sensors have notably garnered considerable attention for their widespread adoption in multiple devices, attributed to their cost-effectiveness, compact design, and high sensitivity to various gases. − For instance, PdO x -CuO x -loaded WO 3 microspheres show a response value of 8.6 to 0.5 ppm methanethiol at 200 °C, while Cr-doped NiO nanoparticles have demonstrated a response of 1.6 to 100 ppb benzyl mercaptan at a temperature of 250 °C . Despite their operation under high-temperature conditions, these gas sensors exhibit unsatisfactory responses, suggesting weak interactions between the sensing materials and target gases.…”