: Green synthesis of ZnO nanoparticles has attracted research attention as a sustainable method of avoiding the destructive effect of chemicals. We synthesized a flower-shaped zinc oxide (ZnO) nanoflower (NF) from sea buckthorn fruit (SBT) by co-precipitation and characterized it using X-ray powder diffraction (XRD), X-ray photo electronic microscopy (XPS), photoluminescence (PL), field emission transmission electron microscopy (FE-TEM), and Fourier-transform infrared (FT-IR) spectroscopy. The ability of the ZnO/NF to degrade cationic and anionic dyes, including malachite green (MG), Congo red (CR), methylene blue (MB), and eosin Y (EY), under ultraviolet illumination was studied. The photocatalyst degraded approximately 99% of the MG, MB, CR and EY dyes within 70, 70, 80, and 90 min of contact time, respectively, at a dye concentration of 15 mg/L, 5 mg/L, SBT-ZnO/NF degraded 100% of the MG, MB, CR and EY dyes within 23, 25, 28, and 30 min, respectively. The results indicate that SBT-ZnO/NFs as synthesized is an inexpensive, non-toxic, rapid, and reusable photocatalyst that can play an enhanced role in wastewater treatment.
Keywords: Congo red; Eosin Y; Methylene blue; UV illumination; dye degradation; malachite green; photocatalysis; sea buckthorn fruit; zinc oxide nanoflower.