Transport and Dielectric Properties of Mechanosynthesized La_2/3Cu₃Ti₄O₁₂ Ceramics

• Main Authors: Mohamad M. Ahmad, Hicham Mahfoz Kotb, Celin Joseph, Shalendra Kumar, Adil Alshoaibi
• Format: Article
• Language: English
• Published: MDPI AG 2021-03-01
• Series: Crystals
• Subjects: giant dielectric constant; mechanosynthesis; impedance spectroscopy
• Online Access: https://www.mdpi.com/2073-4352/11/3/313
• ISSN: 2073-4352

La_2/3Cu₃Ti₄O₁₂ (LCTO) powder has been synthesized by the mechanochemical milling technique. The pelletized powder was conventionally sintered for 10 h at a temperature range of 975–1025 °C, which is a lower temperature process compared to the standard solid-state reaction. X-ray diffraction analysis revealed a cubic phase for the current LCTO ceramics. The grain size of the sintered ceramics was found to increase from 1.5 ± 0.5 to 2.3 ± 0.5 μm with an increase in sintering temperature from 975 to 1025 °C. The impedance results show that the grain conductivity is more than three orders of magnitude larger than the grain boundary conductivity for LCTO ceramics. All the samples showed a giant dielectric constant (1.7 × 10³–3.4 × 10³) and dielectric loss (0.09–0.17) at 300 K and 10 kHz. The giant dielectric constant of the current samples was attributed to the effect of internal barrier layer capacitances due to their electrically inhomogeneous structure.