Synthesis and photocatalytic property of the ZrO2/TiO2 pillared laponite

The ZrO2/TiO2 pillared laponite (Ti-Zr-lap) photocatalysts were prepared with intercalation reaction by supercritical fluid drying (SCFD), and characterized by XRD,TEM, SEM and BET surface area analysis, and the photocatalytic properties of Ti-Zr-lap were investigated by degradation of azo dye acid red B (ARB). The results showed that the ZrO2/TiO2 pillared structures in laponite could be formed, with the mass fraction of (Zr4++Ti4+)/laponite (Xm) increasing, the basal spacing and the BET surface area of Ti-Zr-lap significantly increased. The Ti-Zr-lap used as photocatalyst had the advantages of stable and porous layered structure, large surface area with the anatase type TiO2. Compared with the Ti-Zr-lap dried by air drying, the Ti-Zr-lap dried by SCFD showed better photocatalytic property which was very close to that of P25 TiO2. Using the Ti-Zr-lap as photocatalyst with the optimum Xm of 0.16 and the calcination temperature of 500 °C, under the conditions of the initial concentration of ARB 20 mg/L, photocatalyst concentration of 1.5 g/L and irradiation time 60 min, the decoloring rate of ARB could achieve 98.3%, indicating that the Ti-Zr-lap had excellent photocatalytic property.