Synthesis and Structural, Dielectric and Photocatalytic Properties of (Ti, La)-co-Doped Calcium Ferrite Ceramic Powders

This study reports the effects of titanium and lanthanum doping on the structural, morphological, electrical, optical and photocatalytic properties of CaFe2O4 spinel ferrites. The ceramic powders were prepared by sol-gel method. The X-ray diffraction analysis confirmed well-crystallized single-phase orthorhombic structure for all the compositions. The related parameters such as average particle size, density and lattice strain were calculated. Scanning electron microscopy (SEM) of the samples revealed no significant change in morphology with dopant concentration. The dielectric properties of synthesized ferrites materials were carried out at room temperature. The doped ferrites were found to exhibit high dielectric constant, low loss and enhanced conductivity. The Nyquist plot demonstrated the non-Debye behaviour of the samples. The photocatalytic efficiency was assessed using UV-Vis spectroscopy, which elucidated the narrow energy bandgap of the prepared samples. The photoluminescence study favoured the photocatalytic activity of the doped ferrites. The photocatalytic performance of the prepared samples was demonstrated in the effective degradation of methyl blue under visible-light irradiation. Thus, the (Ti, La)-doped CaFe2O4 ferrites prove to be visible-light photocatalysts exhibiting high efficiency in pollutant degradation.