Affiliation:
1. School of Electronic and Information Engineering, Hubei University of Science and Technology, Xianning 437100, China
2. Key Laboratory of Photoelectric Sensing and Intelligent Control, Hubei University of Science and Technology, Xianning 437100, China
Abstract
High-permittivity Ba(Eu1/5Sm1/5Nd1/5Pr1/5La1/5)2Ti4O12 (BESNPLT) high-entropy ceramics (HECs) were synthesized via a solid-state route. The microstructure, sintering behavior, phase structure, vibration modes, and microwave dielectric characteristics of the BESNPLT HECs were thoroughly investigated. The phase structure of the BESNPLT HECs was confirmed to be a single-phase orthorhombic tungsten-bronze-type structure of Pnma space group. Permittivity (εr) was primarily influenced by polarizability and relative density. The quality factor (Q×f) exhibited a significant correlation with packing fraction, whereas the temperature coefficient (TCF) of the BESNPLT HECs closely depended on the tolerance factor and bond valence of B-site. The BESNPLT HECs sintered at 1400 °C, demonstrating high relative density (>97%) and optimum microwave dielectric characteristics with TCF = +38.9 ppm/°C, Q×f = 8069 GHz (@6.1 GHz), and εr = 87.26. This study indicates that high-entropy strategy was an efficient route in modifying the dielectric characteristics of tungsten-bronze-type microwave ceramics.
Funder
Hubei Province Natural Science Foundation of China
Hubei Province Department of Education Foundation
Ph.D. foundation