Controllable synthesis, photocatalytic and electrocatalytic properties of CeO2 nanocrystals

Uniform CeO2 nanoparticles and nanorods were selectively synthesized through a hydrothermal method, which was followed by calcination. UV-vis diffuse reflection spectra (DRS) exhibited that the obtained powders were responsive to visible light, which might be attributed to the presence of increased oxygen vacancies in the ceria structure. The enhanced photocatalytic activities of the CeO2 nanostructures were comparatively evaluated by the photodegradation of rhodamine B under visible light, which far exceeded those of commercial P25 powders. The mechanism was investigated through carrier trapping experiments. Moreover, a glass carbon electrode (GCE) decorated with the resulting nanocrystals was used to examine their electrocatalytic behavior for p-nitrophenol degradation in a basic solution. The results demonstrated substantially that the obtained CeO2 nanoparticles possess excellent photocatalytic and electrocatalytic activities.