Effect of Non-magnetic Ions Substitution on Structural,Magnetic and Optical Properties of BiFeO3 Nanoparticles

Non-magnetic Zr⁴⁺ ions substituted BiFeO₃ nanoparticles (BiFe_1?x Zr _x O ₃, x = 0.0, 0.03 and 0.10) were synthesized by sol-gel method. X-ray diffraction and Raman studies indicate the rhombohedral phase for all the samples. The particle size decreases with increasing Zr⁴⁺ concentration and varies in the range 20–50 nm. The absorption spectra show the strong absorption of visible light with optical band gap variation 2.27–2.21 eV for pure and Zr-doped BFO nanoparticles. A large saturation magnetization value of 9.33 emu/g is observed for x = 0.03 sample. The reduction in saturation magnetization for x = 0.10 sample is attributed to the dominant role of an increasing number of non-magnetically active Zr⁴⁺ ions, and the formation of Fe–O–Zr coordination with increasing Zr⁴⁺ ions concentration becomes less magnetic sublattice.