Effect of Mg2+ and Sr2+ doping on dielectric and non-ohmic properties in binary compound CaCu3Ti4O12/TiO2 ceramics
Year: 2024
Type: article
Abstract: To improve the dielectric response of capacitive CaCu 3 Ti 4 O 12 /TiO 2 ceramics (referred to as CaCu 3 Ti 4.2 O 12 and abbreviated as Ti02), ceramics were single-doped with either Sr 2+ or Mg 2+ ions and co-doped with Sr 2+ and Mg 2+ ions. Systematically, the effects of single- and co-substitution of Sr 2+ or Mg 2+ and (Sr 2+ , Mg 2+ ) ions on the dielectric constant (ε′), loss tangent (tanδ) and nonlinear properties of Ti02 fabricated by a polymer pyrolysis solution method were investigated. X-ray diffraction analysis showed the cubic perovskite crystalline phase of all prepared ceramics identified within the space group Im-3 . It was found that the grain size of Ti02 decreased substantially with (Sr 2+ , Mg 2+ ) co-doping. Additionally, (Sr 2+ , Mg 2+ ) co-doped Ti02 had higher dielectric thermal stability than either Sr 2+ or Mg 2+ -doped Ti02. Moreover, the co-doped Ti02 revealed a large dielectric response over extended ranges of frequency and temperature, as demonstrated by its outstanding ε′ value of ∼ 4 × 10 4 from 10 2 –10 5 Hz and 20–210 °C, respectively. A very high breakdown field ( E b ) value of ∼ 2579.25 V.cm −1 with a non-linear coefficient (α) of ∼ 10.01 and a minimal tanδ value of ∼ 0.033 were achieved in a co-doped MgSr05-1 ceramic. The noticeable increase in grain boundary resistance ( R gb ) due to a decreased mean grain size and improved potential barrier heights (Φ B ) in all doped Ti02 were responsible for the reduced tanδ and superior dielectric thermal stability.
Source: Results in Physics
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,690
OpenAlex ID: W4402292955