Dielectric properties, microstructure and charge compensation of MnO2-doped BaTiO3-based ceramics in a reducing atmosphere.

Based on the relationship of dipole formation and charge compensation, we prepared BaTiO 3 -based (x %MnO 2 -0.05%Nb 2 O 5 –BaTiO 3 , x %Mn–Nb-BT) ceramics using a solid-phase reaction in air and a reducing atmosphere. The influences of MnO 2 doping and sintering atmospheres on crystal structure, charge compensation and dielectric properties were comprehensively studied. The ion substitution mechanism, solid solubility, and crystallinity of x %Mn–Nb-BT ceramics in different atmospheres were resolved by X-ray diffraction (XRD) and electron paramagnetic resonance (EPR) spectroscopy. X-ray photoelectron spectroscopy (XPS) showed that the percentages of oxygen vacancy and Ti3+ in this system were both affected by MnO 2 doping and the atmosphere due to the reducibility of Mn4+ and the reducing atmosphere. Thus, the influence of doped MnO 2 and the atmosphere on dipole formation and charge compensation was deeply discussed. These results provide further insight into the important role of MnO 2 in improving the anti-reduction performance of BT-based ceramics. [ABSTRACT FROM AUTHOR]