SnO2 Nanostructures: Effect of Processing Parameters on Their Structural and Functional Properties

Zero- and 1D (one-dimensional) tin (IV) oxide nanostructures have been synthesized by thermal evaporation method, and a comparison of their morphology, crystal structure, sorption properties, specific surface area, as well as electrical characteristics has been performed. Synthesized SnO₂ nanomaterials were studied by X-ray diffraction, scanning and transmission electron microscopy (SEM and TEM), N₂ sorption/desorption technique, IR spectroscopy and, in addition, their current-voltage characteristics have also been measured. The single crystalline structures were obtained both in case of 0D (zero-dimensional) SnO₂ powders and in case of 0D nanofibers, as confirmed by electron diffraction of TEM. It was found that SnO₂ synthesis parameters significantly affect materials' properties by contributing to the difference in morphology, texture formation, changes in IR spectra of 1D structure as compared to 0D powders, increases in the specific surface area of nanofibers, and the alteration of current-voltage characteristics 0D and 1D SnO₂ nanostructures. It was established that gas sensors utilizing of 1D nanofibers significantly outperform those based on 0D powders by providing higher specific surface area and ohmic I-V characteristics.