Structural, optical and morphological investigation of bismuth substituted cerium ferrite: An efficient photocatalyst and dielectric material for various applications

Abstract

In this work, Bi-doped cerium ferrite Ce1-xBixFeO3 (x = 0.00, 0.01, 0.03, 0.05, 0.07, 0.09) was synthesized via a simple co-precipitation route. The as-synthesized samples were investigated by UV–visible (UV–Vis) spectroscopy, photoluminescence spectroscopy, vibrational Raman and Fourier transform infrared (FTIR) spectroscopies, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and Brunauer-Emmett-Teller (BET) analyses to study the influence of Bi doping on the optical, structural, morphological and textural characteristics of cerium ferrite. Dielectric studies indicated the charge storage potential of Bi-doped cerium ferrites where a considerable increase in dielectric constant was observed in the case of Ce0.93Bi0.07FeO3 (1.29178 × 107) compared to the pristine cerium ferrite (1.97615 × 10−11) at 20 Hz. Moreover, small loss tan value of Ce0.93Bi0.07FeO3 (1.36704) reflected its ability to store charges with minimum current leakage. The prepared samples were also investigated for the photocatalytic degradation of a strong anti-inflammatory drug i.e. diclofenac potassium in aqueous media. The photocatalytic degradation of diclofenac potassium by Ce0.93Bi0.07FeO3 reached 93% of conversion and was the highest value compared to pristine cerium ferrite (73%), following pseudo-first order kinetics with the rate constant of 0.02038 min−1. This enhanced photocatalytic activity could be attributed to the effective suppression of the charge carriers owed to the crystal defects induced by Bi doping leading to the formation of active species responsible for the degradation of diclofenac. This work established the potential applicability of the ferrite-based composites towards photocatalytic removal of pollutants as well as their use in charge storage devices.