DIFFUSE PHASE TRANSITION AND DIELECTRIC PROPERTIES OF MN4+-DOPED BA0.9CA0.1SN0.06TI0.94O3 PEROVSKITE CERAMICS

In this work, a conventional solid-state reaction technique was used to successfully fabricate lead-free Ba0.9Ca0.1Sn0.06Ti0.94-xMnxO3 (BCSTM) perovskite ceramics, where x = 0.00, 0.03, 0.06, and 0.09. The effect of Mn4+ doping on structure, dielectric properties, and phase transition was investigated. The dielectric constant (ε) of Mn4+-doped BCST ceramics was enhanced by Mn4+ incorporation, as measured by LCR meter at room temperature. The dielectric constant (ε) of 4963 and the low dielectric loss (tanδ) of 0.0241 were obtained at the composition of x = 0.06 at room temperature, with a frequency of 1 kHz. The dielectric property investigation indicated that the degree of the diffuse phase transition behavior increased with Mn4+ substitution. The phase transition from tetragonal to cubic symmetry was significantly dependent on the amount of Mn4+ added. It also was found that the diffuseness of the phase transition behavior of BCST ceramics was enhanced, while the phase transition temperature (TC) of these ceramic samples decreased with an increase in the content of Mn4+. In addition, the diffuseness of the phase transition behavior was enhanced with an increase in the content of Mn4+. The replacement of Mn4+ at the Ti4+ site led to diffuseness and a rapid decrease in the phase transition temperature (TC or Tm).