Preparation of quantum size of tin oxide: Structural and physical characterization

SnO2 NPs were successfully prepared via a hydrothermal method. X-ray diffraction analysis confirmed the rutile tetragonal structure of SnO2 NPs. The crystallite size increased from 1.18 to 5.06 nm with increasing the preparation temperature from 100 to 180 °C. The SEM photography of the products exhibited the agglomeration of the SnO2 nanocrystals to large view particles, while TEM images confirmed the polycrystalline phase and crystallite size those analyzed from XRD. The UV–vis absorption of ethanol suspended SnO2 NPs was measured. The optical band-gap energies (Eg) were significantly blue-shifted due to quantum confinement. Fluorescence spectra came to confirm this shift, where a clear shift in the maximum emission peak was observed. Stokes shift of SnO2 nanocrystals was found to be crystallite size dependent.