水热法制备二氧化铈纳米空心球及其吸附性能研究

Uniform-sized and monodisperse ceria (CeO2) hollow nanospheres were synthesized in a ethylene glycol aqueous solution with cerium nitrate hexahydrate (Ce(NO3)3 6H2O) as cerium sources and polyvinylpyrrolidone (PVP) as surfactant. The synthesized products were characterized by means of Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectrum (XPS), X-ray diffraction (XRD), N2 adsorption desorption and UV-Vis. The results show that the porous CeO2 hollow nanospheres composed of small nanoparticles with cubic fluorite structure; the average diameter and wall thickness of the CeO2 hollow nanospheres were about 400nm and 30 nm respectively; they have a high specific surface area of 76.86 m2g- 1 and BJH pore size about 3~5 nm. On the basis of time-dependent experiment, the relevant formation mechanism was proposed. The ceria hollow nanospheres show an excellent adsorption rate about 70% of heavy metal ions at room temperature for Cr(VI) solutions, which is 3 times higher than that of ceria powder.