57Fe Mössbauer and Magnetism study of Mo6+ and W6+ substituted four-layer Aurivillius Bi5FeTi3O15 compound

• DOI: 10.1007/s10751-021-01747-1
• Publication Date: 2021-10-30T07:02:54Z
• Authors: Deepak Prajapat; Akash Surampalli; V. Raghavendra Reddy
• Keywords: Aurivillius; Magnetism

The present work reports the structural, electrical and magnetic properties of W6+ and Mo6+ substituted four-layer Aurivillius compound, Bi5FeTi3O15 (BFTO). The oxidation states of the dopants and other elements of BFTO are studied from x-ray photo-electron and 57Fe Mossbauer spectroscopy. The substitution resulted in a net increase of magnetic cation (Fe3+) from 25% to about 37.5% in BFTO. However, the magnetization measurements indicate the lack of magnetic ordering even down to 2 K. Further, the high temperature (300-1070 K) dielectric study of these compounds reveal the ferroelectric transition temperature decreases with the increase of magnetic cations in BFTO because of hexavalent W6+ and Mo6+ substitution at Ti4+ site.