Green synthesis of dual-surface nanocomposite films using Tollen’s method

Abstract

Nanocomposite films with dual-surface, silver (Ag) layers and silver-polyvinyl alcohol (Ag-PVA) bulk layers were prepared by Tollen's reagent using β-D-glucose as a green reducing agent in water as an environmentallyfriendly solvent and in PVA as a bio-friendly polymer. The gradual color change of Ag in PVA solutions from colorless to light brown and then to brown, and finally dark brown, indicated the formation of Ag nanoparticles in the bulk of the PVA solution which finally formed Ag layers on the inner side of the glass. Energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD) were used to characterize the nanocomposite films with two surfaces. The Ag content of the Ag layers reached 93% with a higher crystallinity. The Ag content of the Ag-PVA bulk layers reached 10.8% with a lower crystallinity due to incorporation of Ag nanoparticles in the polymer chains. The structure and morphology of the two surfaces were confirmed by scanning electron microscopy (SEM).

Synthesis and characterizations of magnetite nanocomposite films for radiation shielding

“…They are lighter than their metal counterparts, and can be processed to achieve effective shielding for radiations associated with specific industry . The polymer nanocomposites combine the excellent functional properties of nanoparticles with desired properties of host polymers . These improvements concern mechanical properties, surface properties, dimensional stability, thermal stability, chemical stability, antimicrobial properties, photocatalytic, optical, and electrical properties.…”

“…These improvements concern mechanical properties, surface properties, dimensional stability, thermal stability, chemical stability, antimicrobial properties, photocatalytic, optical, and electrical properties. The incorporation of only a few percent of nanosized particles can make dramatic property changes . The surface area, the number of dangling bond atoms, and unsaturated coordination on the surface of the nanoparticles lead to interface polarization and multiple scattering which are useful for absorption of electromagnetic radiations .…”

Green synthesis of nanomaterials - A scientometric assessment

“…This finding demonstrates clearly that the number of scientific terms used in publications on green synthesis of NMs kept increasing. However, key aspects regarding economic considerations have not been discussed in those papers, hence indicating that one of the principles of green chemistry (Table 9) has not yet been appropriately addressed, even in this more recent period (Badawy, 2014;Coman et al, 2014;Huang et al, 2014;Kim et al, 2013;Mtimet et al, 2012;Yan et al, 2013). Concluding, despite being a significant milestone, the application of NMs engineered according to the green synthesis principles remained confined to the lab-scale in many important fields, not spilling over to real applications.…”