Measurement of SnO2 Nanoparticles Coating on Titanium Dioxide Nanotube Arrays Using Grazing-Incidence X-Ray Diffraction

Grazing-incidence X-ray diffraction measurements (GIXRD) were performed on thin films of SnO2 nanoparticles coating on the TiO2-nanotube arrays using a common X-ray diffractometerwith focusing light, Shimadzu XRD-7000. By GIXRD analysis, the phase components of the coating on titanium oxidenanotube arrays were disclosed, and a multi-layer structure is established: SnO2 crystal phase, TiO crystal phase and amorphous phase with SnO2 composition, from the top down, respectively. It is shown from the GIXRD results that, there is obvious diffraction peak broadening phenomenon corresponding to the decreasing X-ray incident angles (ω ≥ 2°) due to the crystals on the surface, which is caused by the nonparallel X-rays scattering on the sample’s surface, while for the crystal under the surface, there is no this phenomenon observed, even for crystals much closer to the surface. This provides a method for distinguishing the crystals on the surface or under the surface.