Magnetically separable BiZnO/Fe3O4 nanocomposites and their application for degradation of 2,4-dichlorophenoxyacetic acid pesticide

This study aimed to increase the photocatalytic activity of ZnO-based magnetically modified nanocomposites to degrade 2,4-dichlorophenoxyacetic acid (2,4-D). The physicochemical properties of the photocatalysts were thoroughly investigated, and the effects of various operational parameters were analyzed. The photodegradation efficiency of the pesticide increased with increasing reaction time. Among the synthesized nanocomposites, 1.5 wt% BiZnO and 1.0 wt% BiZnO/Fe3O4 had the highest photodegradation efficiencies. The photodegradation efficiency using 1.5 wt% BiZnO and 1.0 wt% BiZnO/Fe3O4 nanocomposites were 96 and 94%, respectively. Therefore, it can be concluded that 1.5 wt% BiZnO and 1.0 wt% BiZnO/Fe3O4 samples can effectively degrade the model pollutant, 2,4-D, under sunlight illumination. Additionally, 1.0 wt% BiZnO/Fe3O4 was easily separated by a magnet showing the reusability of the prepared photocatalyst. The mechanistic pathways of 2,4-D are also proposed in this work. The results of these insights offer a holistic understanding of this photocatalyst's role in the field of green and efficient pesticides' photocatalytic degradation.