Preparation of Porous PVDF Nanofiber Coated with Ag NPs for Photocatalysis Application

The porous Polyvinylidene fluoride (PVDF) nanofibers were prepared by leaching method using polyethylene oxide (PEO) as porogen for the first time. The influences of the molecular weight (MW) and concentration of PEO, and the leaching solution on the morphology and the surface area of the porous PVDF nanofiber were systematically investigated. Polyethylene glycol 6000 (PEG6000) showed a better pore-forming effect. Optimized preparation parameters were obtained. With the ratio of PEG6000/PVDF reaching 1:1, the surface area of the resulting porous PVDF nanofiber was about three times higher than that of the pure PVDF nanofiber. Moreover, NaClO solution as leaching solution showed a very limited influence on the surface area of porous PVDF nanofiber. Afterwards, Ag NPs coated PVDF (Ag/PVDF) nanofiber was prepared by physical adsorption of Ag ions and in-situ reduction reaction using sodium borohydride as reductant. The photoactivity of Ag/PVDF nanofiber was evaluated by the photodegradation of methyl orange (MO) under visible light irradiation. Ag/PVDF nanofiber showed a better photoactivity than PVDF-Ag nanofiber prepared by the ex-situ blending method.