Electron probe microanalysis of the dopant concentrations in complex perovskite ferroelectrics

摘要

Quantitative EPMA-WDS microanalyses were applied for the compositional characterisation of complex perovskite ferroelectrics based on cerium-doped barium titanate, a solid solution between lead-magnesium-niobate/lead-titanate and niobium-doped barium-bismuth-titanate. The analyses were optimized for high analytical sensitivity, precision and an ultimate accuracy of ≈ ± 1 % relative. The inherent problem with the WDS peak overlap of the Ce-Lα1 and Ba-Lβ_(1,4) spectral lines was solved by introducing overlap-correction methods in order to obtain consistent quantitative results for the Ce-doped BaTiO3. The quantitative results made it possible to obtain accurate chemical formulae for these materials, to determine the solubility of the dopants as well as to define the mode of the dopant incorporation and the charge-compensation mechanisms.