Enhanced dielectric tunability and reduced dielectric loss tangent in the Mn-doped BaTi0.8Zr0.2O3 ceramics

In the present study, BaTi0.8-xZr0.2MnxO3 (x = 0, 0.25 %, 0.5 %, 0.75 %) ceramics were prepared via a solid-state reaction process. Results showed that both enhanced tunability of 93.4 % (at 20 kV/cm and 27 °C) and reduced dielectric loss tangent of 0.005 at 10 kHz were achieved in BaTi0.8-xZr0.2MnxO3 ceramics at x = 0.5 %. Such dielectric tunability was higher than that of common materials whose tunability hardly exceeded 85 %. Moreover, the mechanism of enhanced dielectric tunability was discussed. The contribution of the intrinsic polarization to the dielectric tunability increased with the increase of Mn content, leading to a higher tunability. Meanwhile, the “domain pinning” effect of MnTi″−VO●●× defect dipoles restricted the reorientation of microdomains, thus decreasing extrinsic contribution and dielectric loss tangent. Furthermore, the tunability for the BaTi0.8-xZr0.2MnxO3 (x = 0 %, 0.25 %, 0.5 %, 0.75 %) samples was measured in the temperature range of − 30 to 85 °C, showing a favorable dielectric tunable performance with good temperature stability.