Facile Fabrication of Hierarchical SnO2 Microspheres Film on Transparent FTO Glass

Hierarchical SnO2 microspheres consisting of nanosheets on the fluorine-doped tin oxide (FTO) glass substrates are successfully prepared via a facile hydrothermal synthesis process. The as-prepared novel microsphere films were characterized in detail by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), UV−vis diffuse reflectance spectroscopy. Moreover, SnO2 nanoparticles with 30−80 nm in size covered on the surface of nanosheets/microspheres were also obtained by optimizing the hydrothermal reaction temperature, time, or volume ratio of acetylacetone/H2O. The detailed investigations disclose the experimental parameters, such as acetylacetone, NH4F, and seed layer play important roles in the morphology of hierarchical SnO2 microspheres on the FTO glass. The formation process of SnO2 microspheres is also proposed based on the observations of time dependent samples.