Photocatalytic activities of cellulose-based nanofibers with different silver phases: Silver ions and nanoparticles

Cellulose acetate (CA) nanofibers with 5 wt% AgNO3 were fabricated by electrospinning. The Ag ions in as-spun CA nanofibers were photo-reduced to Ag nanoparticles (NPs) using a UV irradiation, and the UV-irradiated CA nanofibers were then transformed to cellulose nanofibers containing Ag NPs by deacetylation reaction. The size and content of Ag NPs in CA fibers was further increased under the deacetylation condition. The catalytic activity of the CA and cellulose nanofibers with different Ag ions/NPs ratios was examined by two model reactions; photodegradation reaction of methylene blue (MB) and chemiluminescent (CL) reaction of luminol. The Ag ions played an important role as a reducing catalyst of MB, whereas the Ag NPs are more effective than Ag ions in the CL reaction. Therefore, the CA and cellulose nanofibrous matrices with Ag ions or NPs have diverse potential applications as catalytic membranes for sensing to specific chemicals.