High-efficiency removal of rhodamine B dye in water using g-C₃N₄and TiO₂co-hybridized 3D graphene aerogel composites

The graphitic carbon nitride-titanium dioxide-graphene aerogel (g-C3N4-TiO2-GA) composites were facilely assembled by a hydrothermal approach combined with freeze drying. The adsorptivity for rhodamine B (RhB, 20.0 mg L−1, 25 mL) within 1 h over 5.0 mg of the composites was as high as 96.5% in dark and could be up to 98.4% under visible light irradiation. Furthermore, the resulting composites also displayed satisfactory cyclic stability and the removal efficiency could be 75.6% even after four cycles of removal. In addition, a photocatalytic mechanism was proposed for the composite. The result demonstrated that the g-C3N4-TiO2-GA composites could be effectively used for the elimination of organic dyes under visible light irradiation because of their unique 3D hierarchical porous structure and the synergistic effect among the components.