Controlled deposition of silver nanoparticles on cellulosic nanofibers

CELL 172

Naomi L Birbach, nlb26@cornell.edu1, Hong Dong, jh433@cornell.edu2, and Juan P. Hinestroza, jh433@cornell.edu2. (1) Department of Chemistry, Cornell University, Ithaca, NY 14853, (2) Department of Fiber Science and Apparel Design, Cornell University, 213 Martha Van Rensselaer Hall, Ithaca, NY 14853-7801
The controlled deposition of silver nanoparticles on cellulosic nanofibers is reported. Nonwoven mats of cellulose acetate nanofibers were obtained via electrospinning. A 3:1 acetone / dimethylacetamide solvent system was used. Deacetylation of the cellulose acetate nanofibers was performed using solutions of sodium hydroxide in ethanol. The degree of deacetylation was confirmed using FTIR and monitoring the extinction of characteristic acetate peaks (1740 and 1225 cm-1). Further, treatment of the cellulose fibers with sodium chloroacetate yielded anionic charges on the surface of the cellulose fibers. These negatively charged nanofibers were immersed into a silver nitrate solution for adsorption of silver ions. The adsorbed ions were reduced to silver metal nanoparticles via UV radiation. The coated nanofibers were probed using SEM and TEM revealing conformal coverage of the nanofibers with spherically- shaped particles. These particles were confirmed to be silver via EDS. Cellulose nanofibers are of specific interest as it is the most abundant and renewable polymer. Conformal coating of cellulose fibers can open a new avenue for potential applications including wound dressings, active filtration of bacteria as well as flexible low-pressure drop catalytic mantles.