Preparation and Characterization of Cellulose-Silver Nanocomposites by in situ Reduction with Alkalis as Activation Reagent

A simple, environmentally friendly, and efficient synthesis method for cellulose/silver (Ag) nanocomposites was developed by microwave heating an alkaline aqueous solution of cellulose fiber and silver nitrate (AgNO3), which resulted in good utilization of silver ions and a product with high silver content. The effect of the alkaline compounds and reducing agents on the silver content and utilization rate of silver ions was investigated using atom absorption spectroscopy (AAS). The morphology, size, thermal stability, and surface components of cellulose/Ag nanocomposites were investigated using scanning electron microscopy (SEM), thermogravimetric analysis (TG), differential scanning calorimetry (DSC), and Raman spectroscopy. The alkaline compound and reducing agent influenced the size and shape of the silver nanoparticles. Reduced silver ions had the greatest influence on the surface components of cellulose; however, nano-silver particles exhibited no obvious influence on cellulose's thermal stability. Furthermore, cellulose/Ag nanocomposites exhibited excellent antibacterial activity against Escherichia coli and Staphylococcus aureus.