In this study, magnetic zinc and nickel ferrites were co-precipitated and mechanically mixed to obtain a binary catalyst for the photodegradation of metronidazole (MZ). The catalysts were characterized using techniques of XRD, FTIR, VSM, DRS, SEM-EDX, and X-ray mapping. The crystallite size for NiFe 2 O 4 , ZnFe 2 O 4 , and Zn0.75Ni0.25Fe 2 O 4 was estimated to be 10.1, 4.6, and 35.0 nm (Scherrer model) and 4.3, 3.7, and 18.3 nm (Williamson-Hall model), respectively. Characteristic FTIR absorption bands were observed between 400 and 600 cm -1 . The SEM analysis confirmed the nanoscale morphology, and the EDX analysis indicated uniform particle distribution in Zn 0.75 Ni 0.25 Fe 2 O 4 . DRS measurement revealed band gap energies (Egs) of 1.59, 1.74, and 1.40 eV, for NiFe 2 O 4 , ZnFe 2 O 4 , and Zn 0.75 Ni 0.25 Fe 2 O 4 , respectively. Response Surface Methodology (RSM) was employed to evaluate the combined effects of the experimental variables. The appropriateness of the proposed model was confirmed by ANOVA results using the F-test. The highest MZ photodegradation efficiency was achieved at pH 5, 0.8 g L -1 of catalyst, and 5 mg L -1 MZ under 70 minutes of irradiation.
Sharafzadeh et al. (Fri,) studied this question.