Structure and dielectric properties of Nd substituted Bi1.5MgNb1.5O7 ceramics

• Published in: Journal of materials science. Materials in electronics Vol. 24; no. 8; pp. 2785 - 2789
• Main Authors: Huang, Baoshuai, Liu, Yunfei, Lu, Yinong, Gao, Hong, Chen, Hu
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.08.2013; Springer
• Subjects: Applied sciences; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Dielectric loss and relaxation; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Electronics; Exact sciences and technology; Materials; Materials Science; Optical and Electronic Materials; Permittivity (dielectric function); Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Dielectric Constant; Dielectric Property; Dielectric Loss; Temperature Coefficient; Bi2O3; Grain size; Grain size analysis; Scanning electron microscopy; Dielectric loss; Cubic lattices; Cubic crystals; Dielectric properties; Doping; Multiple layer; Dielectric measurement; Ceramic capacitor; Precipitate; Lattice parameters; X ray diffraction; Pyrochlore type compound; Optimization; Temperature coefficient; Solid state reaction; High k dielectric; High frequency; Permittivity; Ceramic materials; Crystalline structure
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-013-1171-9

New pyrochlore ceramics Bi (1.5− x ) Nd x MgNb 1.5 O 7 with x  = 0–0.6 were synthesized by doping Nd into the A site in the Bi 1.5 MgNb 1.5 O 7 pyrochlore. The Nd substituted Bi 1.5 MgNb 1.5 O 7 ceramics were prepared utilizing solid-state reaction and investigated by X-ray diffraction, scanning electron microscope and dielectric measurements. The crystal structure was characterized as single cubic pyrochlore phase for x  ≤ 0.5 while the second phase appeared at x  = 0.6. With increasing Nd content from 0 to 0.5, the lattice parameters decreased slightly and the average grain size pronouncedly reduced from ~7.5 to ~5.0 μm. The Nd incorporation resulted in attractive enhancement of the dielectric properties including the temperature coefficient of dielectric constant that was remarkably optimized with the lowest value of −16 ppm/°C at x  = 0.5. A good combination of low dielectric loss, superior temperature coefficient and high dielectric permittivity can be achieved for the composition of x  = 0.5, which seems to be very appealing for the practical use in high-frequency multilayer ceramic capacitors.