Eco-friendly Synthesis and Characterization of ZnO and CdS Nanoparticles Using Rhus coriaria Extract for Antibacterial and Antifungal Applications

Abstract This study involved the preparation of ZnO and CdS nanoparticles via a plant-assisted aqueous synthesis method using Rhus coriaria extract, followed by assessment of their structural, optical, and antibacterial properties. We used X-ray diffraction (XRD), UV–Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) to study the nanoparticles we made. The XRD showed that crystalline hexagonal ZnO and CdS phases had formed. The average diameters of the crystals were about 31.2 nm and 41.28 nm, respectively. The UV–Vis investigation showed that ZnO had an absorption band at 370 nm and CdS had an absorption band at 463 nm. These bands correspond to band-gap energies of 3.29 eV and 2.72 eV, respectively. SEM showed that ZnO particles were grouped together and were about 71.9 nm in size, while CdS particles were about 83.39 nm in size. FTIR spectra showed the presence of hydroxyl and organic surface groups, suggesting that plant-based compounds helped stabilize the nanoparticles. Antimicrobial testing showed that both nanoparticles were effective against Klebsiella pneumoniae (22.2 ± 0.6 and 32.1 ± 1.05) mm and Staphylococcus aureus (23.4 ± 0.3 and 33.2 ± 0.6) mm for ZnO and CdS NPs, respectively at 100 mg/mL, although CdS was more effective overall and was the only material that worked against Candida albicans (29.0 ± 1.2) mm. Under the conditions tested, ZnO did not exhibit any antifungal activity. These results show that using Rhus coriaria to produce ZnO and CdS nanoparticles is an effective method, but further research on the mechanisms, surface properties, yield optimization, and toxicity is needed before it can be used in real life.