Green-synthesis of Ag nanoparticles and its composite with PVA nanofiber as a promising Cd2+ adsorbent and antimicrobial agent

Abstract Simple and eco-friendly biosynthesis of Silver Nanoparticle (Ag-NPs) and Silver Nanoparticle supported by Polyvinyl Alcohol and then crosslinked by Glutaraldehyde to form Ag-NPs/PVA-NF using Pomegranate peel extract as the reducing agent. The shape morphologies of the fabricated nanoparticles were characterized by field emission scanning electron microscopy (FE-SEM), crystal structure was investigated by X-ray diffraction (XRD) and nitrogen adsorption/desorption isotherm using for detecting the surface area of the prepared samples. The functionalized groups of prepared samples have been confirmed using Fourier-transform infrared spectroscopy (FTIR). The TEM analysis demonstrate ultrafine nanoparticles with the average particles size ranges about 7–13 nm. To achieve high adsorption capacity of Cd +2 using neat Ag-NPs and Ag-NPs/PVA-NF, the adsorption process was optimized and investigated under various conditions. It was found that the optimum pH for Cd 2+ adsorption was 8 and the equilibrium was reached in 240 min. The Ag-NPs/PVA-NF standalone achieved excellent removal performance with a maximum adsorption efficiency of (40.65 mg/g) compared to pristine Ag-NPs (28.4 mg/g). The adsorption isotherm fitted well to both Langmuir and Freundlich isotherms. The adsorption mechanism was investigated. The positive values of ΔH o indicated that the Cd 2+ adsorption on the Ag-NPs and Ag-NPs/PVA-NF were endothermic in nature. Moreover, the antibacterial activity of Ag-NPs and Ag-NPs/PVA-NF were examined against different species of Gram-Positive and Gram-Negative bacteria revealing significant response for both types. Interestingly, the solution of Ag-NPs/PVA-NF- Cd +2 after adsorption show durable antimicrobial activities. Overall, this proposed route opens new avenue to synthesize different kind of Ag-NPs via facile, green and economic strategy for multifunctional environmental applications.