Effects of sintering temperature on the microstructure and dielectric properties of titanium dioxide ceramics

• Published in: Journal of materials science Vol. 45; no. 24; pp. 6685 - 6693
• Main Authors: Chao, Sheng, Petrovsky, Vladimir, Dogan, Fatih
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.12.2010; Springer; Springer Nature B.V
• Subjects: Analysis; Capacitors; Ceramic materials; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Crystallography and Scattering Methods; Dielectric breakdown; Dielectric constant; Dielectric properties; Dielectric strength; Dielectrics; Diffraction; Electric properties; Electrical conductivity; Electrical resistivity; Flux density; Grain size; Loose powder sintering; Materials Science; Microstructure; Nanostructure; Organic chemistry; Permittivity; Phase transitions; Polymer Sciences; Scanning electron microscopy; Sintering; Solid Mechanics; Tangents; Temperature; Titanium; Titanium dioxide; X-rays; Dielectric Constant; Space Charge Polarization; TiO2 Ceramic; TiO2; Loss Tangent
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-010-4761-4

Nanostructured (~200 nm grain size) titanium dioxide (TiO 2 ) ceramics were densified at temperature as low as 800 °C by pressureless sintering in a pure oxygen atmosphere. Phase transition and microstructural development of sintered samples were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Dielectric properties including d.c. conductivity, dielectric constant, loss tangent, and dielectric breakdown strength (BDS) were determined for samples sintered at various temperatures. The influence of sintering temperature on the microstructural development, defect chemistry, and dielectric properties of TiO 2 is discussed. Nanostructured TiO 2 ceramics with high sintering density (>98%) lead to improved dielectric properties; high BDS (~1800 kV/cm), low electrical conductivity (~5 × 10 −15  S/cm), high dielectric constant (~130), and low loss tangent (~0.09% at 1 kHz), which is promising for application in high energy density capacitors.