A polymer-network gel coating method for BaTiOinf3/inf-based dielectric ceramics with a multilayer core-shell structure

摘要

A modified polymer-network gel route has been developed to prepare a multilayer core-shell structure of BaTiO3-based dielectric ceramics, which greatly improved the efficiency of gelation process. The core particles are BaTiO3, while 0.7 BaTiO3-0.3Bi(Zn1/2Ti1/2)O3 (0.7 BT-0.3BZT) and Nb oxides were coated in order as the shell material. The influences of core-shell structure and ratios on the dielectric properties were studied. The samples of coated BaTiO3 were found to possess optimized temperature stability of dielectric behavior in the temperature range of −55 to 200°C (ΔC/C≤ ± 15%), the dielectric constant at room temperature could reach 1190, with a low dielectric loss at about 1.3%.