SYNTHESIS OF ZnFe2O4/ZnO/C COMPOSITE BASED ON ZIF-11 MATERIAL

The ZnFe₂O₄/ZnO/C composites were synthesized via pyrolysis of ZIF-11 material modified with Fe³⁺ ions. The effect of the Fe:Zn molar ratio on the phase composition of the composites was also investigated. Energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) were employed to characterize the structure and properties of the synthesized materials. The results indicated that ZnFe₂O₄/ZnO/C composites were formed after calcination of the modified material at 600 °C. As the Fe:Zn molar ratio increased, the ZnFe₂O₄ spinel phase became more pronounced. The adsorption and photocatalytic properties of the synthesized ZnFe₂O₄/ZnO/C composites were also evaluated. The experimental results showed that the composites exhibited significantly higher methylene blue (MB) adsorption capacity than the original ZIF-11 material. The adsorption capacity increased with the Fe:Zn molar ratio, reaching 11.72 mg/g, 15.27 mg/g, and 17.99 mg/g for Fe:Zn ratios of 2:8, 3:7, and 4:6, respectively. Furthermore, the ZnFe₂O₄/ZnO/C composites demonstrated photocatalytic activity in the degradation of MB under visible light. A 10 mg/L MB solution was adsorbed and degraded by 45% after 120 minutes of illumination using a catalyst dose of 0.2 g/L