Double-layer capsule of mesoporous ZnO@SnO2 for sensitive detection of triethylamine

Phase-Dependent Dual Discrimination of MoSe2/MoO3 Composites Toward N,N-Dimethylformamide and Triethylamine at Room Temperature

Herein, we present, a chemiresistive-type gas sensor composed of two-dimensional 1T-2H phase MoSe2 and MoO3. Mixed phase MoSe2 and MoSe2/MoO3 composites were synthesized via a facile hydrothermal method. The structure analysis using X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy revealed the formation of different phases of MoSe2 at different temperatures. With increase in synthesis temperature from 180 to 200 °C, the relative percentage of 1T and 2H-MoSe2 phases changed from 80 to 48%. On the other hand, at 220 °C, 2H-MoSe2 was obtained as a major component. The gas sensing properties of individual MoSe2 and composites were investigated at room temperature toward various analytes. The obtained results revealed that composites possess improved sensing features as compared with individual MoSe2 or MoO3. Data also revealed that the composite with dominating 1T-phase exhibits relatively higher response (10%, at 10 ppm) for dimethylformamide (DMF) compared to triethylamine (TEA) (3%, at 10 ppm). In contrast, the composite with larger 2H-phase exhibited affinity toward TEA and had a relative response of about 2%. Therefore, selectivity of a sensor device can be tuned by an appropriately designed MoSe2/MoO3 composite. These results signify the importance of MoO3-based composites with dual-phase MoSe2 for successfully discriminating between DMF and TEA at room-temperature.

Metal Oxide Semiconductor Sensors for Triethylamine Detection: Sensing Performance and Improvements

Triethylamine (TEA) is an organic compound that is commonly used in industries, but its volatile, inflammable, corrosive, and toxic nature leads to explosions and tissue damage. A sensitive, accurate, and in situ monitoring of TEA is of great significance to production safety and human health. Metal oxide semiconductors (MOSs) are widely used as gas sensors for volatile organic compounds due to their high bandgap and unique microstructure. This review aims to provide insights into the further development of MOSs by generalizing existing MOSs for TEA detection and measures to improve their sensing performance. This review starts by proposing the basic gas-sensing characteristics of the sensor and two typical TEA sensing mechanisms. Then, recent developments to improve the sensing performance of TEA sensors are summarized from different aspects, such as the optimization of material morphology, the incorporation of other materials (metal elements, conducting polymers, etc.), the development of new materials (graphene, TMDs, etc.), the application of advanced fabrication devices, and the introduction of external stimulation. Finally, this review concludes with prospects for using the aforementioned methods in the fabrication of high-performance TEA gas sensors, as well as highlighting the significance and research challenges in this emerging field.