The effect of Ce doping on the structural and optical properties of BiFeO 3 nanoparticles via sol-gel method is reported. All samples were a pure phase with perovskite structure. The EDX results show the doped samples contain Bi, Fe, O and Ce elements. The vibrational properties of samples were studied using Raman spectroscopy. Photoluminescence shows an intense peak at 398 nm, the peak strength enhanced greatly and had redshift with the increase of Ce doping concentration. UV-vis results show the samples have a broad absorption band in the range of 500-600 nm. The bandgaps decrease with the concentration increase of Ce doping. It indicates the as-prepared BiFeO 3 can be used as visible light catalyst.

This study reports the effect of Nd-doping on structural, morphological and optical properties of BiFeO 3 synthesized by hydrothermal method. The X-ray diffraction's results indicate that the samples possess single phase up to 12.5 % Nd doping at the Bi site, and all the samples were pure phase microcrystal having a perovskite structure with a space group of R3c. Through the scanning electron microscope, we find that the particles are nearly spherical morphology and the size decreases with Nd doping. The study of Fourier transform infrared spectroscopy confirms the formation of perovskite structure of prepared BiFeO 3 . Photoluminescence spectroscopy shows Nd doping enhanced the Photoluminescence intensity. Ultravioletvisible absorption spectrum shows BiFeO 3 have a wide absorption band in 550-650 nm wavelength range. The corresponding energy band gap of the samples decreases with the increase of Nd-doping concentration. BiFeO 3 valence band electrons will be excited to the conduction band when the wavelength of visible light is 600-800 nm. It can be used in visible light catalysis. The value of remnant magnetization has improved due to the continuing collapse of the space-modulated spin structure of Bi 0.925 Nd 0.075 FeO 3 microcrystals.