KONA Powder and Particle Journal (Jun 2014)
An XPS Investigation of Hydrothermal and Commercial Barium Titanate Powders
Abstract
Hydrothermal and commercial barium titanate powders were examined for undesirable impurity phases. Compositional differences in the powder were evaluated using x-ray diffraction (XRD), x-ray fluorescence (XRF), and x-ray photoelectron spectroscopy (XPS). A barium-rich impurity phase, virtually undetectable by XRD, was detected via XPS. Barium impurity phase peaks were detected at binding energies @1.5 eV higher than those characteristic of barium in a barium titanate bonding state for both the Ba 3d and Ba 4d transitions. Simple curve-fitting techniques were used to quantify the percentage of barium in a barium titanate bonding state versus another barium bonding state for each set of doublets. The barium impurity bonding state accounted for 20-50 mol% of the barium detected by XPS.