Synthesis of TiO 2  graphene oxide-based material for textile effluent decontamination: characterization, kinetic, and mechanism studies.

In this work, a hydrothermal method was proposed to fabricate a nanomaterial composed of titanium dioxide and graphene oxide (10 wt%) (TiO 2 -GO). The GO was synthesized according to the modified Hummers and Offeman method, followed by exfoliation. Several characterization analyses were performed in order to investigate the structure, functional groups, and elemental composition of the nanomaterial. XRD analysis showed that the presence of GO does not change the crystalline structure of TiO 2 . FTIR evidenced the characteristic peaks present in both precursor materials (TiO 2 and GO) and EDX confirmed the presence of GO on the TiO 2 -GO material. The nanomaterial was used as a photocatalyst in the TWW treatment, where the color and COD removal and the decrease of the characteristic peaks presented in the UV-Vis spectrum were investigated. The dosages of TiO 2 -GO and pH were studied to find the optimum operating condition. The results revealed that 0.5 g of photocatalyst with an initial pH of 3 achieve the best results under UV-A radiation. The kinetic test shows a COD removal of 87% after 90 min. The reuse test shows a decrease in COD removal after four cycles attributed to the deposition of some oxidized compounds on the catalyst surface. Finally, the efficiency of the photocatalyst was evaluated under solar radiation and it was shown that despite the good results, the performance of the TiO 2 -GO was better under UV-A radiation.