Ti-rich and Cu-poor grain-boundary layers of CaCu3Ti4O12 detected by x-ray photoelectron spectroscopy

Authors

C Wang, Zhejiang UniversityFollow
H J. Zhang, Zhejiang University
P M. He, Zhejiang University
G H. Cao, Zhejiang University

RIS ID

70094

Publication Details

Wang, C., Zhang, H. J., He, P. M. & Cao, G. H. (2007). Ti-rich and Cu-poor grain-boundary layers of CaCu3Ti4O12 detected by x-ray photoelectron spectroscopy. Applied Physics Letters, 91 (5), 052910-1-052910-3.

Abstract

Cleaved and polished surfaces of Ca Cu3 Ti4 O12 ceramics have been investigated by x-ray photoelectron spectroscopy (XPS) and energy dispersive x-ray spectroscopy (EDX), respectively. While EDX technique shows the identical Ca Cu3 Ti4 O12 stoichiometry for the two surfaces, XPS indicates that the cleaved surface with grain-boundary layers is remarkably Ti-rich and Cu-poor. The core-level spectrum of Cu 2p unambiguously shows the existence of monovalent copper only for the cleaved surface. Possible grain-boundary structure and its formation are discussed.