Synchrotron X-Ray Absorption Study of Cu and Mn Doped BiFeO3-BaTiO3 Multiferroic Ceramics

Abstract

In this work, an experimental X-ray Absorption Spectroscopy (XAS) measurement was employed to determine the local structure and valency of Cu and Mn in BiFeO3-BaTiO3. Synchrotron x-ray absorption near-edge structure (XANES) and extended x-ray absorption fine structure (EXAFS) experiments were performed on Cu-doped and Mn-doped BiFeO3-BaTiO3 samples. The Cu- and Mn-doped BiFeO3-BaTiO3 ceramic samples were used for the XAS experiment. XAS spectra at the Cu and Mn K-edge were recorded in flurorescent mode with 13-element Ge detector. The spectra were collected at ambient temperature with a Ge(111) double crystal monochromator and recorded after performing an energy calibration. The features of the measured Cu and Mn K-edge XANES was consistent with Cu and Mn on the Fe/Ti site and inconsistent with Cu and Mn on other sites. The clear agreement was the strongest evidence of Cu and Mn substituting for B-site in BiFeO3-BaTiO3 materials. In addition, the valency of both Cu and Mn ions in BiFeO3-BaTiO3 materials was also confirmed.