RETRACTED: Effect of Cerium on Structural and Dielectric Properties of Modified BiFeO3-PbTiO3 Ceramics for Photovoltaic Applications (Retracted article. See vol. 51, pg. 4106, 2022)

In this communication, the cerium (Ce) modified (Bi0.4Fe0.4)(Pb0.6Ti0.3Ce0.3)O-3 (BF-PT) ceramics is prepared by conventional solid-state reaction technique. The compound is found to crystallize in the rhombohedral crystal system with space group R-3c (#167). The refined lattice parameters are a = b = 4.989 angstrom, c = 17.062 angstrom, alpha = beta = 90 degrees, gamma = 120 degrees, V = 367.78 angstrom(3) and rho = 2.71 g/cm(3) (JCPDS No.-00-005-0586). The average crystallite size and lattice micro-strain in the ceramics are estimated at 47.6 nm and 0.117% respectively. Scanning electron microscopy analysis indicates low porosity and well-defined grain boundaries, with an average grain size of 13.7 mu m. Raman spectroscopy confirms the presence of all constituent elements and ferroelectric character. Ultraviolet-visible (UV-Vis) spectroscopy analysis suggests a bandgap of 1.72 eV for the modified BF-BT ceramics, which is suitable for photovoltaic applications. The study of complex impedance suggests a Cole-Cole-type relaxation with a decrease in bulk resistance from 6.283 x 10(13) Omega cm(2) at 25 degrees C to 1.783 x 10(4) Omega-cm(2) at 500 degrees C, confirming the negative temperature coefficient of resistance. The calculated activation energies are 849.8 meV, 706.5 meV, 575.1 meV, and 499.4 meV at 1 kHz, 10 kHz, 100 kHz, and 1000 kHz, indicating ionization of oxygen vacancy and the involvement of the released electrons in the hopping conduction process, and support a thermally activated conduction mechanism. The increase in the peak frequency difference between the Z '' and M '' spectrum with temperature suggesting a non-Debye-type relaxation in the material. The material is characterized to a high dielectric constant and low tangent loss suitable for optoelectronic devices.