Facile and green synthesis of well-dispersed Au nanoparticles in PAN nanofibers by tea polyphenols

The green natural compounds, tea polyphenols (TP), were introduced to synthesize well-dispersed Au nanoparticles (AuNPs) in polyacrylonitrile (PAN) nanofibers by combining an in situ reduction approach and electrospinning technique. The AuNPs were firstly synthesized in aqueous solution to test the reducibility of the TP. Then, the well-dispersed AuNPs in PAN nanofibers were obtained by an in situ reduction approach and electrospinning technique. Fourier transform infrared spectroscopy (FTIR) was utilized to confirm the reducibility of TP. The transmission electron microscopy (TEM) and the ultraviolet-visible spectroscopy (UV-Vis) demonstrated the formation of AuNPs and their morphology. Surprisingly, compared with the AuNPs in aqueous solution, the AuNPs in PAN nanofibers via electrospinning were much smaller and well-dispersed and it was attributed to the stabilization effect of PAN through the chelating effect between gold and cyano groups. Apart from the reducibility effect, TP also served as a stabilizer together with PAN to prevent the aggregation of AuNPs effectively, which were testified by X-ray photoelectron spectroscopy (XPS) results.