Green synthesis of rGO nanosheets wrapped on Ni-doped ZnO nanocomposite using P. dodecandra L’Herit (P.d) leaves extract and their photocatalytic and antioxidant performance

The current work focussed on the synthesis and characterization of Ni-doped ZnO/rGO heterostructures and evaluation of its photoactivity under UV light irradiation. The nanocomposite photocatalysts were prepared via green synthesis using P.dodecandra L’Herit (P.d) leaves extract. The X-ray diffraction analysis revealed that Ni and rGO were successfully incorporated into the wurtzite structure of ZnO nanocomposites. FESEM images showed a uniformed particle with the average size of about 10–20 nm for all samples. Later, the photocatalytic degradation of Rhodamine B (RhB) and methylene blue (MB) using the produced materials under visible light irradiation was examined. These results revealed that Ni-doped ZnO/rGO nanocomposites exhibited better photocatalytic performance than ZnO. However, Ni-doped ZnO/rGO composite achieved the highest degradation efficiency for RhB dye approximately 98% under UV light. Moreover, the composite exhibited higher rate constant (0.0156 min⁻¹) and long-term stability. Altogether, the unique properties such as electron accepting and transporting properties of rGO in the nanocomposite enhanced photocatalytic activity by minimizing the charge carrier’s recombination rate. Overall, Ni-doped ZnO/rGO showed better results in antioxidant as well as photocatalytic activity against the pure ZnO NPs. Facile and low-temperature synthesis process with excellent degradation performance demonstrated that the Ni-doped ZnO/rGO nanocomposites have a great potential for wastewater treatment applications.