Storage of energy harvested from a miniature turbine in a novel organic capacitor

• Integrated energy harvesting storage.
• Large levels of charge storage in organic capacitors.
• Synthesized polymers as semiconducting material.
• Pd nanoparticles as storage elements.

The potential of harvesting energy generated from a (5-cm) miniature wind turbine and storing the charge in a novel organic capacitor is experimentally investigated. The energy is generated by subjecting the wind turbine to different flow speeds between 2 and 8 m/s. A maximum output power of 0.2 W was attained with an optimum load resistance of 220 Ω at 8 m/s. The organic capacitor consists of layer-by-layer deposition of synthesized organic semi-conductive polymers, made of doping ionic liquid with non-conductive polymers, and metallic charge element made out of synthesized palladium (Pd) nanoparticles with a diameter of 6 nm. Scanning electron microscopy (SEM) images revealed uniformly distributed Pd nanoparticles over the entire substrate. Capacitance–voltage (C–V) measurements were carried out for the fabricated organic capacitor. The results exhibit large window gates that showed that the Pd nanoparticles are responsible for storing the electric charge. The performance of the organic storage device was evaluated through comparison with a commercial capacitor. The results show that the organic capacitor performed much better at lower frequency values. It was also observed the voltage produced at various airflow speeds was high enough to store the harvested energy in the organic capacitor.