Energy Harvesting Applications from Poly(ε-caprolactone) Electrospun Membranes

Piezoelectricity is associated with crystalline materials that have noncentrosymmetric crystal units. This work reports the electroactive properties of poly­(ε-caprolactone) (PCL) membranes produced by electrospinning. The individual PCL fiber shows an apparent piezoelectric constant of 5 ± 2 pm·V^–1 with a longitudinal piezoelectric voltage coefficient of 0.25 Vm·N^1–. Further, the PCL flexible electronic skin device exhibited superior mechano-sensitivity of 0.098 V·kPa^–1, had the ability to measure small forces (1 mN), presents a remarkable output voltage stability (>16 000 cycles), and could accurately monitor human gait. The overall electroactive properties create opportunities in the development of environmentally friendly and low-cost energy nanoharvesting and wearable devices for human gait applications.