Preparation and properties of TiO2/illite composites synthesized at different hydrothermal pH values

In this experiment, The TiO2/illite composites were synthesized by a simple hydrothermal method, taking Ti(SO4)(2) as Ti precursor and illite as substrate. The as-prepared composites were characterized by XRD, FT-IR, BET, SEM, TEM and photocatalytic performance. The results show that TiO2 particles do not enter the interlayer of the illite because the (0 01) diffraction peak of illite in the composites does not shift. Illite and TiO2 are connected by Si-O-Ti and Al-O-Ti bond and the presence of illite can inhibit the transition from anatase to rutile. Moreover, the dispersion of TiO2 particles in the composite is obviously improved. When the pH value is 1.5, the photocatalytic performance of the composites is the best. The degradation rate of methyl orange (MO) solution can reach 73.4% after 8 h visible light irradiation and 93.6% after 40 min ultraviolet light irradiation, which is better than P25.