Modification of BaTiO3 for diversified applications by single Nd element substitution with wide doping range

In this work, A-site Nd doped BaTiO₃ ceramics in the form of Ba_1−xNd_2x/3TiO₃ with a wide substitution level range of x = 0–0.2 have been prepared via solid-state reaction method. Powder X-ray diffraction results reveal that Nd is completely incorporated into the BaTiO₃ lattice in all specimens. Further analyses based on Rietveld refinement suggest that tetragonal and pseudo-cubic phases coexist in Ba_1−xNd_2x/3TiO₃ ceramics with x ≤ 0.06, and the amount of tetragonal phase is raised with the increase of x value. When x value is larger than 0.08, only pseudo-cubic is observed. The generated \(V^{\prime\prime}_{{{\text{Ba}}}}\), \({\text{Nd}}_{{{\text{Ba}}}}^{\cdot }\) and \(V_{{\text{O}}}^{{\cdot \cdot }}\) defects, which are identified by X-ray photoelectron spectra, make the grain size displays a tendency of decrease first mainly due to the pining effect, and then increase ascribed to the accelerate of mass diffuse. By introducing such wide range of substitution level, Ba_1−xNd_2x/3TiO₃ ceramics with colossal dielectric constant (x = 0.08), temperature-stable dielectric properties (x = 0.15), especially relaxor behavior (x = 0.20) noticed for the first time, are, respectively, received, which is closely related to the variation of phases and defects induced by the addition of Nd. This study may provide a special idea to modify BaTiO₃ to satisfy diversified applications by single element with a wide doping range, and could lay the foundation of future works focusing on the various potential applications of Ba_1−xNd_2x/3TiO₃ ceramics.