Electron Paramagnetic Resonance Investigations of Lanthanide-Doped Barium Titanate: Dopant Site Occupancy
Citations Over TimeTop 22% of 2003 papers
Abstract
Air-fired barium titanate samples doped with cerium, neodymium, samarium, gadolinium, dysprosium, erbium, or ytterbium were examined by electron paramagnetic resonance (EPR). Reducing atmosphere-fired europium-doped barium titanate was also investigated with EPR. Each dopant was studied in both Ba- and Ti-rich (Ba/Ti = 1.01, 0.99) samples. Point charge calculations were used to predict the EPR spectrum of each lanthanide in A- and B-sites. Different EPR spectra are expected for A- versus B-site substitution when Ce3+, Sm3+, Dy3+, and Yb3+ are the dopants. The experimentally observed Ba/Ti doping behavior of Ce3+ in BaTiO3 suggests that as a 3+ cation it is on the A-site. No EPR active signal was observed for Sm3+ in BaTiO3. Eu2+ and Gd3+, as previously discussed in the literature, were found to be an A-site dopant and amphoteric, respectively. Dy3+ was found to be a B-site dopant with an EPR signal intensity suggesting amphoteric behavior, whereas Yb3+ showed only B-site occupancy. Nd3+ and Er3+ could not easily be assigned to a particular site by EPR methods alone. We also discuss the lanthanide dopant's effect on the observed levels of titanium vacancies, barium vacancies, and Mn2+ impurities.
Related Papers
- → Application of the co-luminescence effect of rare earths: simultaneous determination of trace amounts of samarium and europium in solution(1989)32 cited
- → Dy 3+ → Eu 3+ Energy Transfer in SrLaGa 3 O 7 :Dy 3+ /Eu 3+ Phosphors(2021)4 cited
- → Spectrofluorimetric determination of europium and samarium as their 2-naphthoyltrifluoroacetone- trioctylphosphine oxide complexes(1969)18 cited
- → Simultaneous determination of samarium, europium and terbium with quinaldic acid and phenanthroline by synchronous derivative fluorimetry(1994)12 cited
- Fluorecence Spectra of Europium-Dysprosium Mixed Sulfoxide Complexes(2003)