High-Frequency EPR Analysis of MnO₂-Doped [Bi_0.5Na_0.5]TiO₃-BaTiO₃ Piezoelectric Ceramics - Manganese Oxidation States and Materials ‘Hardening’

摘要

High-frequency electron paramagnetic resonance (EPR) has been used to identify different manganese oxidation states in the 0.5 mol% MnO ₂ -doped (100−x)Bi _0.5 Na _0.5 TiO ₃ -xBaTiO ₃ (BNT-xBT) solid solution with x=6. The as-sintered and air-annealed samples show two distinct EPR resonances that were assigned to Mn 2+ - and Mn 3+ -ions, respectively, incorporated at the Ti-site. The equilibrium between acceptor-type Mn″ _Ti - and Mn′ _Ti -states can be explained by the thermodynamic equilibration under air at the sintering temperature corresponding to [n][p], which yields an n-type Mn:BNT-6BT compound.View full textDownload full textKeywordsPiezoelectrics, bismuth titanate, defect structure, manganese doping, high-frequency EPRRelated var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/00150193.2012.675831