Effects of annealing temperature on structural, morphological, and photocatalytic properties of TiO2/rGO nanocomposites

In this research, the hydrothermal synthesis was used to prepare nanocomposites titanium dioxide/reduced graphene oxide (TiO2/rGO) with additional annealing at different temperatures (300 °C, 400 °C, and 500 °C). The TiO2 colloidal sol was prepared using titanium (IV) isopropoxide (Ti(C3H5O12)4, TTIP) as a precursor. Graphene oxide (GO) was synthesized using graphite flakes (≤50 µm) by a Hummer’s method. The prepared photocatalysts were characterized by means of Fourier transforms infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and Raman spectroscopy. The photoactivity of nanocomposites was evaluated by the degradation of Rhodamine B (RhB) dye as a model of an organic pollutant. Tests were performed under sun-like irradiation. It was found that the annealing temperatures have an influence on the investigated properties of as- prepared nanocomposites.