Hierarchical PbZr_xTi_1–xO₃ Nanowires for Vibrational Energy Harvesting

Perovskite piezoelectric material nanostructures have gained immense interest in the energy harvesting community due to their ability of converting mechanical energy into electric power in a much more efficient manner. In this paper, we first successfully synthesized PbZrxTi1–xO3 (PZT) nanowires with unique hierarchical nanostructures that are ∼100 nm in diameter and 6 μm in length by using a facile hydrothermal process. Then, a unimorph cantilever energy harvester was fabricated by bonding mixed hierarchical PZT nanowires with a polydimethylsiloxane (PDMS) polymer matrix to a brass substrate. The measured open-circuit voltage from this harvester was 2.7 V at its fundamental resonance (25.2 Hz) under a 0.1g root-mean-square (RMS) acceleration input, and the measured power density was 51.8 μW cm–3 with an optimal load resistance of 2 MΩ, which is approximately 8 times larger than that of the commercial BaTiO3 nanoparticle energy harvester on the same scale but driven by a much higher acceleration level.