Piezoelectric materials can generate an electric field from mechanical deformation or experience mechanical deformation from an applied electric field. These materials have polarization structures depending on the crystal atoms and formation, with nanocrystals having dipoles aligned in one direction and polycrystallines having varying polar axis directions between regions. Piezoelectric nylon-11 fibers are demonstrated as viable for energy harvesting from low frequency vibrations and motion sensors, with nylon-11 capable of a piezoelectric δ'-phase that shows strong piezoelectric activity among its various crystalline phases.