Structural, Optical, Dielectric and Magnetic Properties of Cu Doped BiFeO3 Nanoparticles Synthesized by Sol Gel Method

Nanoparticles of pure and Cu doped BiFeO3 of the composition BiFe(1-x)CuxO(3-delta) (x = 0%, 1%, 3%, 5%) have been successfully synthesized by sol gel method using citric acid as a chelating agent. The so prepared materials were examined for structural, optical, dielectric and magnetic properties using XRD, SEM, UV-Visible, FTIR, LCR and VSM measurements. The crystallite size as determined by powder X-ray diffraction technique is found to decrease with the increase in Cu content. The energy band gap obtained from UV-Visible spectrophotometer is found to increase gradually with Cu doping. The identification of the various chemical bonds present in the pure and Cu doped samples has been carried out through Fourier Transform Infrared spectroscopy. The complex dielectric constant, complex impedance and a.c. conductivity have been studied as function of frequency and composition using LCR, and the obtained results have been explained on the basis of Maxwell-Wagner model. The magnetic measurements done using VSM show increase in magnetization with the increase in Cu concentration.