Hydrothermal Synthesis of TiO_2 Hollow Spheres Using Rapeseed Pollen Grains as Template

TiO_2 precursor/pollen grain core-shell composite materials were prepared by hydrothermal synthesis under ultrasound irradiation by using rapeseed pollen grains as template.The core of the pollen grain could be removed by calcination at 550℃for 6h and the TiO_2 hollow spheres were consequently obtained.SEM,TG,XRD,FTIR and N_2 adsorption were used to characterize the TiO_2/pollen grain core-shell composites and the hollow titania spheres.The results indicate that the ultrasound irradiation helps the dispersion of TiO_2 precursor on the pollen grains' surface uniformly and the suitable amount of tetrabutyl titanate is 6.6g/g pollen,the proper temperature for the hydrothermal synthesis is 105℃. The final TiO_2 hollow spheres with pure anatase phase,have narrow mesopore-size distribution,with an average pore radius of 1.9nm and BET surface area of 26.76m~2·g~(-1).