ABSTRACT
This study reports the synthesis of (Cd0.4Ni0.4Mn0.2)Fe2-xRuxO4 nanoparticles (NPs), where x = 0.00, 0.005, 0.01, 0.015, 0.02, and 0.04, via co-precipitation method. The synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), and photoluminescence (PL) spectroscopy. The results confirmed the purity of the samples with the presence of a very small fraction of the hematite phase. Pseudo-spherical morphology was recognized from TEM images. Then, the prepared samples were further used as effective photocatalysts for the degradation of nitrobenzene under UV irradiation to examine the effect of doping on the photocatalytic activity. Among the synthesized samples, (Cd0.4Ni0.4Mn0.2)Fe1.985Ru0.015O4 NPs exhibited superior photocatalytic activity. This result is in good agreement with photoluminescence (PL) analysis in which (Cd0.4Ni0.4Mn0.2)Fe1.985Ru0.015O4 NPs revealed the slowest recombination rate of the electron-hole pair. To further improve the photocatalytic performance, different weight % of graphene was incorporated with (Cd0.4Ni0.4Mn0.2)Fe1.985Ru0.015O4 NPs. Finally, 81.41% of nitrobenzene was degraded after 180 min in the presence of 5 wt% graphene/(Cd0.4Ni0.4Mn0.2)Fe1.985Ru0.015O4 nanocomposites, and the degradation rate constant was estimated as 8.4 × 10-3 min-1.