Single-Step Synthesis of Silver Nanoparticles Supported on Cellulose Nanofibers Using a High-Pressure Wet-Type Jet Mill and Their Catalytic Activities

Abstract

Silver nanoparticles (AgNPs) on the surface of cellulose nanofibers (CNF) were immobilized using a high-pressure wet-type jet mill to increase their stability while maintaining their catalytic activity. As a raw starting material, an aqueous silver nitrate solution was mixed with a CNF suspension. The mixture was then processed five times using the high-pressure wet-type jet mill at a discharge pressure of 100 MPa. AgNPs with an average particle size of 3.8 ± 0.8 nm were immobilized and well-dispersed on the surface of CNF, as observed by transmission electron microscopy. The catalytic activities of the AgNPs coated with PVP (Ag–PVP) and the prepared AgNPs-supported on CNF composite (Ag–CNF) were evaluated. As a result, the catalytic activity of Ag–CNF was discovered to be 2.32 times greater than that of Ag–PVP. The catalytic activity was measured in terms of the number of runs because Ag–CNF can be easily recovered by centrifugation or filtration. Even the catalytic activity of Ag–CNF after five runs was maintained at 62%, but the catalytic activity gradually decreased as the number of runs increased.

Fig. 2 Transmission electron microscopy images and particle size distribution histograms of (a) Ag–CNF and (b) Ag–PVP, respectively.