When the doping content is below 6 wt.%, there is no second phase, and samples showed regular microstructures.

pan id="mmlsi1" class="mathmlsrc">pan class="mathContainer hidden">pan class="mathCode">${\left({\text{Zn}}_{1/3}^{2+}{\text{Nb}}_{2/3}^{5+}\right)}^{4+}$pan>pan>pan> replaced Ti⁴⁺ forming chemically inhomogeneous structure, affecting the curie peak of BT.

With more doping content (7.5 and 9 wt.%), Ba₂Ti₅O₁₂ and ZnNb₂O₆ were detected.

Flake microstructure was found in BZNT4 with 7.5 wt.% doping content.

ZnNb₂O₆ phase was very effective to reduce the size of the grains and improve the BDS.