Photocatalytic degradation of acid orange 7 using Cr-doped CeO_2 nanorods

摘要

Cr-doped CeO_2 nanorods were prepared by a co-precipitation method using cerium and chromium nitrates with ammonia solution as the precipitator. The morphology and structure of the synthesized products were characterized by field emission scanning electron microscope, X-ray diffraction, and transmission electron microscopy. The specific surface area of the Cr-doped CeO_2 nanorods (455 m~2 g~(-1)) is higher than those of CeO_2 nanoparticles (52 m~2 g~(-1)). X-ray photoemission spectros-copy spectrum confirms the presence of Cr in CeO_2 nanorods. UV-Vis spectra analyzes showed that the Cr-doped CeO_2 nanorods exhibit the absorption band in the visible region. The synthesized products exhibited good photocatalytic activity for the degradation of acid orange 7 under UV-visible light illumination and the pseudo-first order reaction rate constant (k) of 0.250 h~(-1) for Cr-doped CeO_2 nanorods is higher than 0.142 h~(-1) of CeO_2 nanoparticles.