Fabrication of SiO2 and SnO2 composite nanofibers in order to increase the photocatalytic degradation under ultraviolet light.

In this research, core-shell SiO2/SnO2, SnO2/SiO2 composite nanofibers, and SnO2 nanofibers were synthesized by electrospinning method and were calcined in an electric furnace at temperature of 500 degrees Celsius for 2 hours. Photocatalytic degradation ability of synthesized nanofibers was studied on Crystal violet, methylene blue and methyl orange dyes under ultraviolet light. Structural characteristics of core-shell SnO2/SiO2 nanofibers, SiO2/SnO2 and SnO2 nanofibers were investigated using field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), X-ray diffraction spectroscopy (XRD), and Fourier transform infrared spectroscopy (FT-IR), energy diffraction X-ray spectroscopy (EDX) and Xmap analysis. TEM images clearly show the core-shell structure of SiO2/SnO2 and SnO2/SiO2 nanofibers with an average diameter of 550 nm. XRD analysis shows the amorphous structure of nanofibers before thermal treatment and the formation of the dominant crystalline phase after thermal treatment. Uniform distribution of elements was observed by Xmap analysis. The comparison of photocatalytic decomposition of methylene blue, methyl orange and crystal violet dyes in the presence of SnO2 single layer nanofibers, core-shell SnO2/SiO2 nanofibers and SiO2/SnO2 shows that core-shell SiO2/SnO2 nanofibers with 40.58 percent decomposition in methylene blue, 44/44 in methyl orange and 12/31 in crystal violet had the most effect in destroying colors.