Effect of Particle Size on Magnetic and Dielectric Properties of Nanoscale Dy-Doped BiFeO3
In the present report, influence of Dy-substitution and size on the structural, magnetic and dielectric properties of BiFeO3 nanoparticles has been investigated. The synthesis of pure and Dy-doped BiFeO3 nanoparticles has been done successfully using sol–gel method. Size of Dy-doped BiFeO3 nanoparticles was tailored by varying the calcination temperature. Structural analysis reveal that substitution of Dy3+ leads to a change in structure from rhombohedral (x=0) to orthorhombic (x=0.15). The average crystallite size varies from 6 to 15 nm. Magnetic study reveals the enhancement in magnetization with the doping of Dy3+. Further, this value decreases as the particle size increases. Dielectric property improves with the Dy3+ substitution. All the nanoparticles display Debye-type relaxation. The low dielectric loss values observed are attributed to the nanosized grains. Remarkably, enhanced saturation magnetization value (13.8 emu/g) and dielectric constant value (95.8) were observed for Dy-doped BiFeO3 nanoparticles having the smallest particle size. Thereby, the study indicates strong correlation between size and multiferroism.
KeywordsSize-dependent Nanoparticles Magnetic materials Dielectric Ferromagnetism
This research work is supported by Government of India, Department of Atomic Energy (DAE), Board of Research in Nuclear Sciences (BRNS) vide sanction No. 2012/37P/48/BRNS.