摘要： Cerium oxide is of crucial importance for intrinsic redox reaction, which is attributed to the active sites neighboring oxygen vacancies. However, the role of oxygen vacancy (Ov) on the various properties of ceria ?lms remains to be elucidated. Herein, ceria ?lms were deposited by magnetron sputtering and the e?ect of electric current intensity on the creation of Ov was systematically investigated. X-ray photoelectron spectroscopy (XPS) results show that the Ce4+ concentration decreases with the increase of current intensity, which demonstrates that Ov can be created and tuned during ?lm deposition by controlling electric current intensity. The ?lm fabricated by 6 A current intensity has 42% Ce4+, approaching that of rhombohedral-Ce7O12, which is a stabilized bulk phase ceria. X-ray di?raction patterns reveal that 6 A ?lm shows mixed crystalline phases with the majority of peaks very close to rhombohedral-Ce7O12, while 1 A, 2 A, and 4 A ceria ?lms show simple crystalline phase. Raman analysis presents that dioxygen species are heavily absorbed on the surface of 6 A ?lm with more active sites on di?erent crystalline surfaces, which is con?rmed by photocatalytic degradation of Methylene Blue. The calculated bandgap by DFT (density functional theory) + U is consistent with that obtained from Tauc plots curves. This work demonstrates that Ov plays an important role on the properties of the ceria ?lm.