Tuning the concentration of surface/bulk oxygen vacancies in CeO_(2) nanorods to promote highly efficient photodegradation of organic dyes

To enhance the photodegradation ability of CeO_(2) for organic dyes,an effective strategy is to introduce oxygen vacancies(Vo).In general,the introduced Vo are simultaneously present both on the surface and in the bulk of CeO_(2).The surface oxygen vacancies(Vo-s) can decrease the band gap,thus enhancing light absorption to produce more photogenerated e-for photodegradation.However,the bulk oxygen vacancies(Vo-b) will inhibit photocatalytic activity by increasing the recombination of photogene rated e-and Vo-b.Therefore,regulating the concentrations of Vo-s to Vo-b is a breakthrough for achieving the best utilization of photogene rated e-during photodegradation.We used an easy hydrothermal method to achieve tunable concentrations of Vo-s to Vo-b in CeO_(2) nanorods.The optimized CeO_(2) presents a 70.2%removal of rhodamine B after 120 min of ultraviolet-visible light irradiation,and a superior photodegradation performance of multiple organics.This tuning strategy for Vo also provides guidance for developing other advanced metal-oxide semiconductor photocatalysts for the photodegradation of organic dyes.