Affiliation:
1. Provincial Key Laboratory of Informational Service for Rural Area of Southwestern Hunan, Shaoyang University, Shaoyang 422000, China
2. School of Physics and Electronics, Central South University, Changsha 410083, China
Abstract
Ba1−xSrx(Zn1/3Nb2/3)O3 (BSZN) perovskite ceramics are prepared using the traditional solid-state reaction method. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) were used to analyze the phase composition, crystal structure, and chemical states of BSZN ceramics, respectively. In addition, the dielectric polarizability, octahedral distortion, complex chemical bond theory, and PVL theory were investigated in detail. Systematic research showed that Sr2+ addition could considerably optimize the microwave dielectric properties of BSZN ceramics. The change in τf value in the negative direction was attributed to oxygen octahedral distortion and bond energy (Eb), and the optimal value of 1.26 ppm/°C was obtained at x = 0.2. The ionic polarizability and density played a decisive role in the dielectric constant, achieving a maximum of 45.25 for the sample with x = 0.2. The full width at half-maximum (FWHM) and lattice energy (Ub) jointly contributed to improving the Q × f value, and a higher Q × f value corresponded to a smaller FWHM value and a larger Ub value. Finally, excellent microwave dielectric properties (εr = 45.25, Q × f = 72,704 GHz, and τf = 1.26 ppm/°C) were obtained for Ba0.8Sr0.2(Zn1/3Nb2/3)O3 ceramics sintered at 1500 °C for 4 h.
Funder
Natural Science Foundation of Hunan Province
Scientific Research Fund of Hunan Provincial Education Department
Graduate scientific research innovation project of Shaoyang University
Subject
Chemistry (miscellaneous),Analytical Chemistry,Organic Chemistry,Physical and Theoretical Chemistry,Molecular Medicine,Drug Discovery,Pharmaceutical Science