Abstract In this study, nylon‐6 nanofiber mats containing Fe 2+ ions were fabricated via electrospinning. The resultant electrospun nylon‐6/ FeCl 2 nanofiber mats were characterized by SEM , TEM , Fourier transform IR spectroscopy, wide angle XRD and DSC . Unique morphological features, such as spider's‐web‐like morphologies, were observed and became evident with increasing additive Fe 2+ ions. The metastable γ form was predominant in the as‐spun nylon‐6 nanofibers. The relative intensity of such γ form gradually decreased with increasing additive Fe 2+ ions, indicative of transformation of the crystalline structure in the electrospun nylon‐6/ FeCl 2 nanofibers due to strong molecular interactions between the nylon‐6 backbone and the additive Fe 2+ ions. The effects of additive Fe 2+ ions on the mechanical properties of both nonwoven nanofiber mats and single nanofibers were investigated. In particular, Young's modulus of nylon‐6/ FeCl 2 single nanofibers gradually increased from 1.46 to 5.26 GPa with increasing additive Fe 2+ ions. © 2013 Society of Chemical Industry