Comparison of fabrication methods for the effective loading of Ag onto PVA nanofibers

We investigated and compared three different methods for synthesizing Ag/PVA nanofibers by effectively dispersing and loading Ag particles onto PVA nanofibers and preventing the detachment of Ag from the nanofibers. The three methods were: (a) the solution reduction method (Method 1) in which the reduction of Ag+ was conducted before electrospinning, resulting in mixing the polymer and the Ag nanoparticles in the electrospinning solution; (b) the immersion method (Method 2) in which electrospun PVA nanofibers were immersed in the Ag+ solution, resulting in loading the Ag particles onto the PVA nanofibers; and (c) the nanofiber reduction method (Method 3) in which the Ag+/PVA solution underwent electrospinning followed by the reduction process with Ag+/PVA nanofibers. All of the electrospun nanofibers had a crosslinked structure that resulted from the chemical reaction of glutaraldehyde with the hydroxyl group of PVA, to prevent dissolution in the aqueous solution. Fourier transform infrared spectra provided evidence of the successful formation of the crosslinked structure of the nanofibers, and x-ray photoelectron spectroscopy and transmission electron microscopy confirmed the loading of Ag nanoparticles onto the nanofibers. The release profiles were investigated by inductively coupled plasma, and the morphology of the nanofibers was observed by scanning electron microscopy. Method 3 had the best performances for loading Ag particles onto the nanofibers and for minimizing the loss of Ag nanoparticles from the nanofibers. These findings identified an effective method for fabricating metal/polymer composite nanofibers, and will allow the expansion of the applications of metal/polymeric composite nanofibers