A green approach to synthesis of ZnO nanoparticles using jujube fruit extract and their application in photocatalytic degradation of organic dyes.

Zinc oxide nanoparticles (NPs) were synthesized using a green method in the presence of jujube fruit extract as a reducing agent and a stabilizer. The characteristics of the NPs were determined by various analyses, including transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared (FTIR), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The results suggest that high quality ZnO NPs in terms of size distribution and morphology were synthesized. The obtained NPs were then used as photocatalyst to degrade two organic dyes, methylene blue (MB) and eriochrome black-T (ECBT) in a model wastewater under direct sunlight. The kinetics of photodegradation of the aforesaid organic dyes was also studied. ZnO NPs exhibited a great photocatalytic performance, which resulted in degradation efficiencies of about 92% and 86% within 5 h at the rate constants of 8.7 × 10-3 min-1 and 6.7 × 10-3 min-1 for MB and ECBT, respectively. Moreover, the NPs demonstrated stable photocatalytic activity after sequential degradation experiments.