Synthesis, Characterization of Tin Dioxide Nanowires by Hard Template Method and Their Gas Sensing Properties

摘要

In this paper, we present a facile strategy to prepare SnO_2 nanowires by wet impregnation of SnCl_2 solution using the mesoporous silica SBA-15 as the hard template. The prepared SnO_2 nanowires were characterized using X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The obtained SnO_2 nanowires have a diameter of about 7 nm after removing the silica template using 5 wt% HF aqueous solutions at room temperature. The gas sensing measurement results show that the SnO_2 nanowires synthesized by the method exhibit higher sensitivity to 100 ppm ethanol and higher selectivity to ethanol against carbon monoxide and hydrogen at relatively low temperature. The response and recovery time are 4 and 10 s, respectively. The results indicate that the good sensing properties have close correlation to the small-size nanocrystals and unique structure of SnO_2 nanowires.