Photocatalytic degradation of indigo carmine using Nd-doped TiO2-decorated graphene oxide nanocomposites

A series of neodymium-doped titanium dioxide (Nd-TiO2) decorated on graphene oxide (GO) were synthesized by sol-gel method. The structures, morphologies and optical properties of the nanocomposites (Nd-TiO2-GO) were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy. The photocatalytic study of Nd-TiO2-GO nanocomposites was evaluated via the degradation of indigo carmine under simulated solar light. Results demonstrated that the photodegradation efficiency of indigo carmine solutions irradiated by solar simulated light for 3 h with the nanocomposites used as a catalyst reached a level of 92 % (0.6 % Nd). This high photocatalytic degradation of indigo carmine solutions by the Nd-TiO2-GO nanocomposites is ascribed to the spherical nanocrystalline size of TiO2.