Green Synthesis of Zinc Oxide Nanoparticles Using Ziziphus Jujuba and Syzygium Jambolanum Leaf Extracts; A Sustainable Approach with Enhanced Photocatalytic Activity

Abstract Zinc oxide (ZnO) nanoparticles (NPs) were synthesized through a green, biogenic approach using aqueous leaf extracts of Ziziphus jujuba and Syzygium jambolanum . This eco‐friendly, cost‐effective, and nontoxic method enabled the rapid production of ZnO NPs with desirable physicochemical features. Characterization was carried out using various analytical techniques. UV–vis spectrophotometry confirmed the synthesis via characteristic absorption peaks. X‐ray diffraction (XRD) patterns verified the crystalline wurtzite structure, while FT‐IR spectroscopy identified phytochemicals responsible for the reduction and stabilization of the NPs. SEM and TEM analyses revealed the morphology and size distribution of the nanoparticles. TEM results indicated that ZnO NPs synthesized using Z. jujuba and S. jambolanum had average sizes of 28.7 and 30.2 nm, respectively. In comparison, chemically synthesized ZnO NPs showed more aggregation, a polydispersed nature, and a broader size distribution with a smaller average size of 24.6 nm. The photocatalytic activity of the synthesized ZnO NPs was tested by degrading Acid Black 1 (AB1) dye under natural sunlight, following pseudo‐first‐order kinetics. The green‐synthesized ZnO NPs achieved about 90% dye degradation within 60 min at pH 7. These results highlight the promise of biogenic synthesis for producing effective ZnO NPs suitable for environmental remediation, especially in wastewater treatment.