Comparative studies of wet-stretched and non-stretched electrospun PVDF-HFP nanofibers

The recent growth in portable electronics has sparked a demand for alternative energy sources. Energy harvesters that utilize piezoelectric materials are promising in capturing the mechanical energy from body movement to power portable electronics. This study investigated the characteristics of PVDFHFP nanofibers created from traditional electrospinning and a novel technique called wet-stretching electrospinning. The solution was initially processed using the traditional method, flat-plate electrospinning, which resulted in a fiber network with random orientations. When performing electrical testing the fibers produced minimal voltage. The solution was then processed utilizing a novel wet-stretching electrospinning technique that allowed for fiber alignment and dynamic stretch ratios. Fibers that underwent this method produced higher voltages than fibers from the traditional electrospinning method. It was observed that fibers processed using the wet-stretching technique with different draw ratios (DR) such as 1 (DR 1) and 2.5 (DR 2.5) showed enhanced piezoelectric properties. This research suggests that the wet-stretched PVDF-HFP nanofibers are better suited for piezoelectric applications than traditionally electrospun nanofibers.