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The energy consumption of MOS (metal oxide semiconductor) sensors has always been a challenge in improving their performance. In this study, bougainvillea‐like Au/ZnO nanostructures were successfully synthesized using the hydrothermal method and the sol fixation technique. The composition, crystallinity, crystal structure, and morphology of the materials were characterized using X‐ray diffraction, energy‐dispersive spectroscopy, and field emission scanning electron microscopy. The experimental results confirm the successful synthesis of a substantial quantity of bougainvillea‐like Au/ZnO nanostructures through nanoparticle self‐assembly. The sensitive performance of the bougainvillea‐like Au/ZnO sensor was evaluated using a CGS‐8 intelligent gas‐sensitive analysis system. Results demonstrate that modification of ZnO with Au in a bougainvillea‐like nanostructure significantly enhances sensitivity to ethanol vapor compared to those of unmodified material sensors. Specifically, the optimal work temperature was greatly reduced by 64%, whereas the sensitivity increased approximately 12 times and the response time decreased nearly 5 times. The significantly enhanced ethanol sensitivity can be attributed to the precious metal modification and unique three‐dimensional morphology. It provides the necessary experimental exploration for reducing energy consumption and improving the performance of MOS gas sensors. [ABSTRACT FROM AUTHOR]

Photophysics and photochemistry of 2,2-diphenylhexamethyltrisilane (1) were studied. Diphenyltrisilane 1 had an intense fluorescence band assignable to the intramolecular charge transfer (ICT) band in a polar solvent. While silylene extrusion and 1,3-silyl migration were the primary photoreactions of 1 in a nonpolars solvent, there was substantial solvolytic cleavage of the Si-Si bond in an ethanol-hexane mixture with the ICT state causing the latter reaction.

ZnO is often used as gas sensor. In order to increase the sensitivity of the sensors, many methods are used to change the gas‐sensing properties. In this paper, ZnO was synthesized by hydrothermal method using Zn (NO3)2 as a zinc source. Sodium lauryl sulfate (SDS) and polyvinylpyrrolidone (PVP) were added into the system to control microstructure and surface morphology of ZnO nanoparticles. The SDS was kept constant, and the PVP was changed. The morphology and composite were investigated by field emission scanning electron microscopy and X‐ray diffraction. The chemical valence of the elements was determined by X‐ray photoelectron spectroscopy. The sensing properties were investigated at different PVP components. It is found that ZnO has a red zinc structure. When the mSDS:mPVP = 1:1, the sensing sensitivity is best. The mechanism of equivalent matching structure optimization performance is proposed. [ABSTRACT FROM AUTHOR]

Carbon nanotubes-coated/filled by Fe3O4 nanoparticles were successfully fabricated by a facile in-situ coprecipitation method at low temperature. The effects of the adding amounts of Carbon nanotubes (CNTs) on the morphology, structure, magnetic and adsorption properties of the nanocomposites were studied in detail. The XRD patterns showed that the sizes of Fe3O4 nanoparticles in the nanocomposites could be well tuned from a few nanometers to a dozen nanometers. The SEM and TEM images revealed that different coverage density and composite mode had happened between CNTs and Fe3O4 nanoparticles. All of the nanocomposites exhibited favorable superparamagnetic properties, and the saturation magnetization was affected by the average grain sizes and the loading amounts of Fe3O4 nanoparticles. Strong magnetization and high dispersion of Fe3O4/CNTs nanocomposites implied the excellent adsorption capacity and recycle of nanocomposites in the practical application. The adsorption kinetics of methylene blue (MB) was well described by the pseudo-second-order kinetic model. [ABSTRACT FROM AUTHOR]