The influence of interface on the dielectric and tunable properties of BCZT/BZT ceramic

Bilayer structure may be a good and convenient strategy to enhance the tunable properties of ceramics, while it has been investigated rarely. In this work, BCZT, BCZT/BZT and BZT ceramics are prepared via solid-state sintering to investigated the influence of interface on the dielectric and tunable properties. An undeteriorated tunability (43%) and reduced loss tangent (0.0031) are achieved in BCZT/BZT ceramic. Shannon additive rule and series equivalent circuit model are used to understand the undeteriorated tunability. Current density–electric field hysteresis loops and insulation resistance confirm that the lower loss tangent achieved in BCZT/BZT ceramic results from the interrupted moving paths of carriers at interface. Due to the reduced loss tangent and undeteriorated tunability, the FOM of BCZT/BZT ceramic (138) is higher than that of BCZT (69) and BZT (97) ceramics. The results make BCZT/BZT ceramic have a great application potential in tunable microwave devices.