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Photocatalysis is well-known as an effective tool for the removal of pollutants but its eco-friendly aspect has not been well explored in the literature. In this study, we prepared an ultraviolet-active photocatalyst by the growth of cerium oxide/sulfide nanoparticles in the zeolite channels via a facile coprecipitation method. The photocatalyst was comprehensively characterized by different analysis methods and showed good activity toward removal of acetamiprid, ACP, a commonly used insecticide. As the main focus of the current work, an in vivo bioassay was carried out to investigate the acute toxicity of the contaminant solutions before and after photoreaction. Accordingly, acetamiprid and the phototreated solutions were orally injected to different groups of laboratory rats. The results indicated that the number of white blood cells and hemoglobin level of the rats exposed to the phototreated solutions decreased from 7.57 ± 1.17 and 15.47 ± 0.85–6.15 ± 0.84 and 14.07 ± 1.31, respectively, compared to the control group’s pathological markers. Also, the level of ALT and AST enzymes increased from 268 ± 33 and 66.7 ± 19.2–375 ± 29 and 98.7 ± 32.3, respectively, indicating the liver dysfunction. These results along with the weight loss and increase in body temperature verified that unlike the pristine ACP solution, the phototreated solutions induced significant toxicity to the laboratory rats. In addition, liquid chromatography-mass spectrometry analysis was served to clarify the toxicity assessment results and propose a suitable photoproduct generation pathway.

The synthesis of Nd2CuO4-Nd2O3 photosensitive nanocomposites by a combined electrochemical deposition-pyrolysis method is reported for the first time. The X-ray diffraction powder (XRD) analysis was well demonstrated the formation of the Nd2CuO4 tetragonal and Nd2O3 hexagonal (partially cubic) phases in the heterostructures. Scanning electron microscopy (SEM), energy dispersive x-ray (EDX), fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectra (DRS), and Brunauer–Emmett–Teller (BET) specific surface area analysis methods were also used to characterize the samples. The results of DRS analysis showed that the photocatalyst has the band gap of 3.3 eV describing its response to ultraviolet (UV) photons. The catalytic activity was evaluated by photodegradation of two semivolatile organic compounds (SVOCs) i.e., 4-methoxy-2-nitrophenol (4Mx2Np) and 3-methyl-4-nitrophenol (3M4Np) which are known as important pollutions in the atmosphere. The pH effect, kinetics and mechanism of the photoreactions were also discussed. The recycling experiments were also performed and the results indicated that the prepared photocatalysts have high capacity for subsequent removal of the pollutants under ultraviolet light.