Sol–gel elaboration and comprehensive characterization of CdFe₂O₄: an efficient photocatalyst for the visible light-driven degradation of malachite green and neutral red dyes

We have successfully synthesized cadmium ferrite spinel CdFe₂O₄ powder via the sol–gel route and meticulously evaluated its efficacy as a photocatalyst for the eradication of Green Malachite (MG) and Neutral Red (NR) dyes from wastewater. Our synthesized samples underwent comprehensive characterization employing a suite of analytical techniques including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and UV–Visible measurements. The XRD analysis unequivocally confirmed the formation of CdFe₂O₄ at 700 °C, showcasing a distinct cubic phase structure. Moreover, FTIR spectroscopy unveiled two typical bands at 412 cm⁻¹ and 603 cm⁻¹ for the studied spinel. SEM imaging revealed a unique microstructure characterized by aggregated pseudo-spherical grains of varying sizes and a plethora of pores. BET analysis demonstrated that the prepared CdFe₂O4 powder boasted a substantial specific surface area of 9.58 m²/g along with a notable pore volume. Our optical and photocatalytic assessments elucidated CdFe₂O₄ spinel powder as a semiconductor material featuring a band gap of 2.37 eV, showcasing commendable photocatalytic activity against the targeted dyes. Noteworthy is the attainment of a remarkable removal efficiency of 79.07% for MG and 92.34% for NR following a mere 180 min of exposure to visible light irradiation.