Insights into microstructural evolution from nanocrystalline SnO2 thin films prepared by pulsed laser deposition -: art. no. 165314

Low-dimensional nanostructures of SnO2 thin films with the interesting features of the tetragonal rutile structure have been prepared by pulsed laser deposition. The microstructural evolution of nanocrystalline SnO2 thin films has been investigated using x-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, and Raman spectroscopy. Experimental results indicate that the as-prepared SnO2 thin films appear to be of polycrystalline state, have a large amount of defects, such as oxygen vacancies, vacancy clusters, and local lattice disorder at the interface and surface, and the appearance of a new Raman peak. It suggests that this new Raman peak is closely related to a surface layer of nonstoichiometic SnOx with different symmetries than SnO2, or in other words, the new peak marks an additional characteristic of space symmetry of the grain agglomeration of nanocrystalline SnO2. The study of the microstructural evolution of nanocrystalline SnO2 is significant for the understanding of the whole structure feature of nanomaterials and for the fabrication of new nanomaterials with favorable properties.