Sustainable silver nanoparticle-decorated reduced graphene oxide with enhanced aqueous dispersibility for PVA nanocomposite films with multifunctional performance

The reduced graphene oxide (rGO), a two-dimensional nanomaterial with a large aspect ratio, exhibits good chemical stability and electrical conduction. Its applicability could be boosted by making its water-dispersible composite with metallic nanostructures like silver nanoparticles (SNPs). This study focuses on the synthesis and characterization of sustainable SNP-decorated reduced graphene oxide (SNP@rGO) nanosheets for poly(vinyl alcohol) (PVA) nanocomposite films having opto-mechanical potential. The SNP@rGO nanofillers were synthesized using eco-friendly reductants, including sodium citrate and chitosan, through a hydrothermal approach. The resulting nanofillers were characterized using advanced analytical techniques. The XRD analysis revealed that the resultant SNP@rGO nanocomposites retained the face-centered cubic crystal structure for metallic silver. The use of sodium citrate as a reductant resulted in highly crystalline SNP@rGO nanocomposites. SEM images confirmed the successful impregnation of spherical SNPs on the rGO nanosheets. FTIR results indicated interactions between SNPs and residual oxygen functionalities on the rGO nanosheets. The SNP@rGO-mediated PVA nanocomposites demonstrated superior performance, exhibiting up to 97% UV-blockage and a remarkable superoxide dismutase activity of 7.2 U/mg with enhanced mechanical strength and antibacterial properties compared to pristine PVA and SNP-loaded PVA films. Incorporating SNP@rGO into PVA enhanced its optical properties, rendering it suitable for optical applications. This investigation paves the way for using SNP@rGO/PVA nanocomposites in cutting-edge fields such as optical devices, biomedical coatings, and packaging materials.