Eur. Phys. J. B 71, 377-381 (2009)
https://doi.org/10.1140/epjb/e2009-00252-x

Effect of chemical modification on the structure and dielectric and magnetic properties of multiferroic (1 – x)BiFeO₃-xDyFeO₃ solid solution

¹ Department of Chemistry and 4D LABS, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada
² Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Xi'an Jiaotong University, Xi'an, 710049, P.R. China

Corresponding authors: ^a zye@sfu.ca - ^b wren@mail.xjtu.edu.cn

Received: 7 March 2009
Revised: 19 April 2009
Published online: 21 July 2009

Abstract

The solid solution of (1-x)BiFeO₃-xDyFeO₃ was prepared by solid state reactions in the form of ceramics. The effects of chemical modification by means of aliovalent ionic substitution of Ti⁴⁺ for Fe³⁺ on the structure and dielectric properties were investigated. A morphotropic phase boundary bridging the perovskite rhombohedral phase and the orthoferrite orthorhombic phase was identified at x around 0.1. The chemical modification was found to stabilize the perovsite phase. The dielectric performance of the solid solution was improved by the substitution of Ti⁴⁺ for Fe³⁺, which decreased the electric conductivity by reducing oxygen vacancies, as evidenced by the decrease in loss tangent values. Magnetic hysteresis and large saturated magnetization (0.5 μ_B/f.u.) were realized in 0.92BiFeO₃-0.08DyFeO₃ with 2% substitution of Ti⁴⁺ for Fe³⁺, which is believed to arise from the disruption of the spiral spin modulation after structural modification, and the interaction between the spins of the Dy³⁺ and Fe³⁺ at low temperatures which decouples the antiferromagnetic order between the Fe³⁺ ions.