Synthesis and Optimization of TiO 2 /Graphene with Exposed {001} Facets Based on Response Surface Methodology and Evaluation of Enhanced Photocatalytic Activity

Response surface methodology (RSM) was employed to optimize the control parameters of TiO2/graphene with exposed {001} facets during synthesis, and its enhanced photocatalytic activities were evaluated in the photodegradation of toluene. Experimental results were in good agreement with the predicted results obtained using RSM with a correlation coefficient (R2) of 0.9345. When 22.06 mg of graphite oxide (GO) and 2.09 mL of hydrofluoric acid (HF) were added and a hydrothermal time of 28 h was used, a maximum efficiency in the degradation of toluene was achieved. X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) were employed to characterize the obtained hybrid photocatalyst. The electron transferred between Ti and C retarded the combination of electron–hole pairs and hastened the transferring of electrons, which enhanced the photocatalytic activity.