Ratio effect of salt fluxes on structure, dielectric and magnetic properties of La,Mn-doped PbBi2Nb2O9 Aurivillius phase
| Autor: | Zulhadjri, Syukri Arief, Tio Putra Wendari, Jacob Baas, Nandang Mufti, Graeme R. Blake |
|---|---|
| Přispěvatelé: | Solid State Materials for Electronics |
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Ferromagnetic material properties Aurivillius phase Oxide Analytical chemistry 02 engineering and technology Dielectric 01 natural sciences Aurivillius chemistry.chemical_compound Impurity Phase (matter) 0103 physical sciences FERROELECTRIC PROPERTIES Materials Chemistry Molten salt 010302 applied physics biology Process Chemistry and Technology Double-exchange interaction 021001 nanoscience & nanotechnology biology.organism_classification Ferroelectric behavior Surfaces Coatings and Films Electronic Optical and Magnetic Materials chemistry Ceramics and Composites Molten salt method Orthorhombic crystal system 0210 nano-technology |
| Zdroj: | Ceramics International, 46(10), 14822-14827. ELSEVIER SCI LTD |
| ISSN: | 0272-8842 |
| DOI: | 10.1016/j.ceramint.2020.03.007 |
| Popis: | The double-layer Aurivillius phase Pb0.4Bi2.1La0.5Nb1.7Mn0.3O9 was synthesized by a molten salt method using a K2SO4/Na2SO4 flux. The effect on the crystal structure, morphology, dielectric and magnetic properties of varying the molar ratio of the oxide precursors to salt flux was investigated. Single-phase products with an orthorhombic structure were obtained for oxide to salt ratios of between 1:5 and 1:9, whereas for lower concentrations of salt a pyrochlore impurity phase is found in the products. SEM showed anisotropic plate-like grains, the size of which increases for larger salt ratios. An investigation of the magnetic properties showed the presence of mixed Mn3+ and Mn4+; the unit cell volume of the single-phase products decreases as the proportion of salt increases, which implies a higher proportion of smaller Mn4+ cations. This can be explained by the oxide ion donating properties (oxobasicity) of the molten salt mixture, which produces an oxidizing environment during synthesis. The best dielectric properties are obtained for an oxide to salt ratio of 1:7, exhibiting relaxor ferroelectric behavior. This is also the ratio at which the most pronounced ferromagnetic properties are observed, resulting from double-exchange interactions between Mn3+ and Mn4+ the proportions of which are approximately equal. Pb(0.4)Bi(2.1)La(0.5)Nb(1.7)Mn(0.3)O(9 )synthesized under these conditions thus exhibits optimal multiferroic properties. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect