Uniform silver nanoparticles synthesized on the surface of the TEMPO-oxidized cellulose nanofibers

Abstract In this study, we developed a method for the uniform synthesis of silver nanoparticles (AgNPs) on TEMPO-oxidized cellulose nanofibers (TOCNFs). The AgNPs were synthesized by a two-step reaction nucleating the carboxyl groups of water-dispersed TOCNFs followed by a local silver mirror reaction, and the Ag-CNF composites with the AgNPs were obtained. The spatial distribution, size, and quantity of the AgNPs were investigated. Transmission electron microscopy (TEM) successfully revealed a uniform distribution of AgNPs on nanofibers. Small angle X-ray scattering (SAXS) analysis showed that the AgNPs with an average size of 2.5 nm and a standard deviation of 1.5 nm were achieved. Thermal gravimetric analysis (TGA) showed a significant increase in the number of AgNPs included in Ag-CNFs with decreasing the D-glucose concentration in the reaction. Differential scanning calorimetry (DSC) showed that the melting point of the AgNPs was 214 °C, which was significantly lower than that of the bulk silver. These results suggest that the Ag-CNF composites synthesized in this study could be promising candidates for applications in conductive inks and electronic devices, taking advantage of their low melting point and electrical resistance.