Green Synthesis of Zinc Oxide Nanoparticles Using Yemeni Sidr Honey as a Bio-Templating Agent

Zinc oxide (ZnO) nanoparticles are versatile semiconductor materials with applications in photocatalysis, gas sensing, optoelectronics, and biomedical fields. Conventional chemical synthesis routes often involve toxic reagents and synthetic surfactants, creating demand for environmentally benign alternatives. This study reports a green sol-gel synthesis of ZnO nanoparticles using Yemeni Sidr honey (from Ziziphus spina-christi) as a natural bio-templating and capping agent, eliminating the need for added synthetic surfactants. In the synthesis, 12 g of Sidr honey was dissolved in 60 mL deionized water under stirring at 70°C for 60 min. Then 10 g zinc nitrate hexahydrate was added, and the mixture was stirred on a sand bath at 70°C for 8 h until a viscous gel formed. The gel was calcined in air at 450°C for 3 h, yielding a white ZnO powder. The product was characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM). FTIR showed a strong Zn–O stretching band at 470 cm -1 , along with surface-adsorbed hydroxyl and carbonate species; bands associated with organic functional groups were not detected after calcination. XRD confirmed a single-phase hexagonal wurtzite structure (JCPDS 36-1451) with no detectable impurity phases, and the average crystallite size calculated using the Scherrer equation was 24.3 nm. FESEM images revealed predominantly spherical particles with hexagonal facets and noticeable agglomeration. The results indicate that Yemeni Sidr honey can serve as an effective natural template in a simple, low-cost, and non-toxic sol-gel route to ZnO nanoparticles. This approach may be extendable to the synthesis of other transition metal oxide nanostructures, although further optimization and property evaluation are needed.