Dielectric characteristics of B-site-modified hexagonal-barium titanate

Cr, Sb co-substituted hexagonal BaTiO3 perovskite ceramics with a composition of BaTi1-2xCrxSbxO3 (x = 0-0.2) were synthesized via the conventional solid-state reaction method. Their structures transitioned from tetragonal (x = 0) with space group P4 mm to hexagonal (x = 0.1) with space group P63/mmc and finally to hexagonal containing impurities (X = 0.2). The refinement results of the sample (x = 0.1) revealed that it is possible to stabilize the hexagonal polymorph of BaTiO3 at room temperature by the partial replacement of Ti4+ with Cr3+ and Sb5+. Moreover, the structural changes of BaTiO3 depend on sintering method and temperature of sintering. The ceramic dielectric properties were studied, and the results showed that with increased doping, the ceramic dielectric constant gradually decreased. All ceramics materials with a composition of BaTi1-2xCrxSbxO3 (x >= 0.075) are dielectric insulators at room temperature with permittivity values between 30 and 60.