The assembly of dendrimer-stabilized gold nanoparticles onto electrospun polymer nanofibers for catalytic applications†
We report here a facile approach to assembling low generation poly(amidoamine) (PAMAM) dendrimer-stabilized gold nanoparticles (Au DSNPs) onto electrospun polymer nanofibrous mats for catalytic applications. In this study, Au DSNPs formed using amine-terminated generation 2 PAMAM dendrimers as stabilizers were assembled onto electrospun polyacrylic acid (PAA)/polyvinyl alcohol (PVA) nanofibrous mats either through electrostatic interactions or through the covalent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) coupling reaction. The assembly of Au DSNPs with a mean diameter of 5.4 nm onto the electrospun nanofibrous mats was characterized via different techniques. The catalytic activity of the Au DSNP-assembled nanofibrous mats was evaluated by the transformation of 4-nitrophenol to 4-aminophenol. We show that both approaches enable the efficient assembly of Au DSNPs onto nanofiber surfaces and the as prepared Au DSNP-containing nanofibers formed via both approaches have excellent catalytic activity and reusability. However, the Au DSNP-assembled nanofibers via electrostatic physical interactions display a much higher catalytic activity than those formed via the chemical assembly approach. The facile dendrimer-mediated assembly approach to modifying electrospun nanofibers may be used to fabricate other composite nanofiber systems for applications in catalysis, sensing, and biomedical sciences.