Structural, dielectric and magnetic properties of Ba3SrLn2Fe2Nb8O30 (Ln = La, Nd, Sm) filled tungsten bronze ceramics

Abstract

Structural, dielectric and magnetic properties have been investigated for Ba 3 SrLn 2 Fe 2 Nb 8 O 30 (Ln=La, Nd, Sm) ceramics. The single phase tetragonal filled tungsten bronze structure in space group P4/mbm is obtained for Ba 3 SrLa 2 Fe 2 Nb 8 O 30 , while such tungsten bronze major phase is determined together with minor amount of secondary phases in Ba 3 SrNd 2 Fe 2 Nb 8 O 30 and Ba 3 SrSm 2 Fe 2 Nb 8 O 30. The saturated magnetic hysteresis loops with enhanced M r are obtained in the present ceramics at room temperature comparing to the Ba 4 Ln 2 Fe 2 Nb 8 O 30 (Ln=La, Nd, Sm) ceramics. Meanwhile, the typical relaxor behaviors are determined: a broad dielectric peak with strong frequency dispersion and the peak temperature following well with the Vogel-Fulcher relationship.

Preparation and dielectric properties of co-contained unfilled tungsten bronze ceramics Ba4RCo0.5Nb9.5O30

“…synthesized Ba6CoNb9O30 ceramics to indicate nature of the relaxor ferroelectric, a wide dielectric peak and frequency dispersion. The maximum dielectric constant value of Ba6CoNb9O30 ceramics is about 100 higher than the Ba3SrLn2Fe2Nb8O30 ceramics as previously reported [8,11]. Guo et.…”

“…When ionic radius decreases, permittivity maximum temperature (Tmax) increases. This is because of the occupancy of different valence and ionic radii in the same position, resulting in the Fe/Nb dipole deviating from the center, and the long-range order at low temperature is disrupted by the distribution field, thus facilitating the formation of relaxor ferroelectrics [8][9][10]. In this article, we also investigated the influence of A site substitution, but we used Co to dope B site.…”

Variation of electrical properties with structural vacancies in ferroelectric niobates (Sr0.53Ba0.47)2.5−0.5Na Nb5O15 ceramics

“…Ferroelectric crystals with tetragonal tungsten bronze structure (TTB) are important ferroelectric materials. Their interesting dielectric and ferroelectric properties have attracted extensive research activities studying on their structural and physical properties due to the compositional flexibility [1,2]. The TTB structure consists of a complex array of distorted BO6 octahedron sharing corners in such a way, that three different types of interstices (pentagonal A2, square A1, and trigonal C sites)…”

Study of Structural and Dielectrical Properties of Lead Free Polycrystalline Electro Ceramics Ba<SUB>5</SUB>CaTi<SUB>2</SUB>Nb<SUB>8</SUB>O<SUB>30</SUB> (BCTN) for Microwave Tunable Device Applications

“…Ganguly et al [8] have been reported the structural, dielectric and electrical studies of Ba 5 SmTi 3 Nb 7 O 30 ferroelectric ceramics. Wang Chen et al [9] …”