Oxygen Vacancies Enhance Triethylamine Sensing Properties of SnO2 Nanoparticles

In this paper, tin oxide (SnO2) nanoparticles with abundant oxygen vacancies (OVs) (designated as IWBT) were synthesized via a combined hydrothermal route and ice-water bath stirring method. In addition, another SnO2 nanoparticles (designated as RTT) were prepared by the room temperature stirring synthesis and subsequent hydrothermal process. The morphology and composition of the as-obtained samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) analysis. It was found that IWBT contained much more surface oxygen vacancies defects than RTT. The synthesized IWBT exhibited outstanding gas sensing properties toward triethylamine (TEA) at 260 degrees C, such as high response, significant selectivity, low detection limit and excellent repeatability. According to the results of experiments, the response of as-prepared IWBT sensor could reach to 2701.36 when exposed to 500 ppm TEA, which was far higher than the as-prepared RTT sensor (748.10). The excellent sensing characteristics of IWBT could be attributed to the abundant OVs that could improve the O-2 adsorptivity and electron transfer capability of SnO2. Thus, IWBT supplied a rational strategy to enhance the gas sensing performances of TEA gas sensors.