Preparation and dielectric properties of Ba4−xSm2Fe2−xNb8+xO30 tungsten bronze ceramics with an adjustable structure that changes from filled to unfilled

摘要: Abstract Tungsten bronze (TB) structural ceramics with the nominal formula Ba 4-xSm2Fe2−xNb8+xO30 (BSFN) (x = 0, 0.025, 0.05, 0.075 and 0.1) were prepared using a standard solid-state sintering method. The effects of 2+ concentration on crystallographic phase, microstructure, dielectric ferroelectric properties systematically studied. All compounds presented tetragonal tungsten (TTB) structures, where A1 A2 sites exclusively occupied by Sm 3+ Ba2+ ions, respectively, while Fe3+ Nb5+ ions randomly distributed between B1 B2 sites. BSFN exhibited normal behavior, but showed an increasing dispersion as decreased. conductive behavior was due to bulk grain boundaries, direct current conductivity increased from 0.67 0.77 eV reduction in 2+. polarization-electric field (P-E) current-electric (I-E) loops all P-E became more slanted slimmer reduced concentration.