Multiferroic Behavior of Lead-free AlFeO3 and Mn, Nb Doped Compositions

Author(s)

Santos, G. M. ^[1] ; Silva, D. M. ^[1] ; Freitas, V. F. ^[1] ; Dias, G. S. ^[1] ; Coelho, A. A. ^[2] ; Pal, M. ^[3] ; Santos, I. A. ^[1] ; Cotica, L. F. ^{[3, 1]} ; Guo, R. ^[3] ; Bhalla, A. S. ^[3]

Affiliation

^[1] Univ Estadual Maringa, Dept Phys, Maringa, Parana - Brazil

^[2] Univ Estadual Campinas, Inst Fis Gleb Wataghin, Campinas, SP - Brazil

^[3] Univ Texas San Antonio, Dept Elect & Comp Engn, San Antonio, TX 78249 - USA

• Document type: Journal article
• Source: Ferroelectrics; v. 460, n. 1, p. 108-116, FEB 17 2014.
• Web of Science Citations: 6

Abstract

The lead-free AlFeO3-based compounds are attractive multiferroic materials, as those present piezoelectricity and ferrimagnetism at low temperatures. In this work the synthesis and ferroic properties of AlFeO3-based ceramics were investigated. Stoichiometric proportions of the precursors - alpha-Fe2O3 and alpha-Al2O3 - were milled and sintered to obtain AlFeO3 ceramics. Also, AlFeO3 ceramics doped with 2at% of Nb2O5 or MnO2 were sintered in oxygen flow at 1700K. The crystal structure of the samples was studied by X-ray diffraction. The diffractograms were refined by the Rietveld method. The results obtained from refinements showed an orthorhombic symmetry with space group Pna2(1). Dielectric, ferroelectric and magnetic investigations suggested a magnetoelectric coupling between the electric and magnetic orderings at temperatures below similar to 160K for AlFeO3, Al(Fe0.98Nb0.02)O-3 and Al(Fe0.98Mn0.02)O-3, where the compositions show the ferromagnetic and ferroelectric ordering. (AU)

• FAPESP's process: 08/04025-0 - Nanostructured multifunctional multiferroic materials: synthesis, properties, phenomenology and applications
• Grantee: José Antonio Eiras
• Support Opportunities: Research Projects - Thematic Grants