Origin of Color Centers in the Perovskite Oxide CeAlO3

Abstract

In view of the significant impact of color centers on the physical and chemical properties of materials, studies on the origin of such color centers are needed. In this article, detailed crystal structure analysis and compositional characterization of CeAlO₃ was carried out by applying XRD, XPS, HRTEM, STEM-EDS and ICP-OES techniques. The results revealed that crystal defects may be the main cause of color centers. The existence of oxygen and aluminum vacancy was proved and confirmed by the application of XPS, ICP-OES and STEM-EDS characterization methods. Overall, it unlikely that a single crystal defect would generate the yellow-green color of CeAlO₃ crystals.

Keywords: X-ray photoelectron spectroscopy; color centers; crystal defects; perovskites; rare earth elements.