STUDY OF STRUCTURE, DIELECTRIC AND TRANSPORT PROPERTIES OF CaCu3Ti4-XNbXO12

• Main Author: Agustina, Elsye
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/35103
• Institution: Institut Teknologi Bandung

CaCu3Ti4O12, well known as CCTO, is a material that has a high dielectric constant, reaching 105, which is an insulator at room temperature. The value of dielectric constant is relatively independent of temperature. This high dielectric constant property is potentially to be applied in electronic devices, for example is allows the miniaturization of electronic elements such as capacitive energy storage in small sizes. This research aims to study the structure, dielectric properties, and transport of CaCu3Ti4-xNbxO12 with the value of x varies from 0 to 3. Nb5+ is expected to increase the polarity of the compounds that will increase the conductivity and permittivity of the compound. In addition, the possibility of metal-insulator transition, which successfully occurred in SrTi1-xNbxO3 compounds, was also investigated. The effect of Nb substitution to the dielectric constant of compounds and whether compounds will likely to be ferroelectric was also learned. CaCu3Ti4-xNbxO12 synthesis is performed by solid state reaction. The characterization is done by X-ray diffraction, four probe conductivity measurement, and capacitance measurements. All of the compounds that have been synthesized in this study have remains structure at the level of Nb substitution up to 20% (cubic with symmetry Im ), although for up to 75% Nb substitution, the original phase is still dominant. Increasing the concentration of Nb also increase the electrical conductivity, but the transition to metallic properties were not observed. Capacitance measurement resulted in increasing relative permittivity according to the concentration of Nb added.