Mechanical Energy Harvesting Performance of Ferroelectric Polymer Nanowires Grown via Template-Wetting.

Nanowires of the ferroelectric co-polymer poly(vinylidenefluoride--triufloroethylene) [P(VDF-TrFE)] are fabricated from solution within nanoporous templates of both "hard" anodic aluminium oxide (AAO) and "soft" polyimide (PI) through a facile and scalable template-wetting process. The confined geometry afforded by the pores of the templates leads directly to highly crystalline P(VDF-TrFE) nanowires in a macroscopic "poled" state that precludes the need for external electrical poling procedure typically required for piezoelectric performance. The energy-harvesting performance of nanogenerators based on these template-grown nanowires are extensively studied and analyzed in combination with finite element modelling.

Vertically aligned zinc oxide nanowires electrodeposited within porous polycarbonate templates for vibrational energy harvesting.

A piezoelectric nanogenerator has been fabricated using a simple, fast and scalable template-assisted electrodeposition process, by which vertically aligned zinc oxide (ZnO) nanowires were directly grown within a nanoporous polycarbonate (PC) template. The nanowires, having average diameter 184 nm and length 12 μm, are polycrystalline and have a preferred orientation of the [100] axis parallel to the long axis. The output power density of a nanogenerator fabricated from the as-grown ZnO nanowires still embedded within the PC template was found to be 151 ± 25 mW m(-3) at an impedance-matched load, when subjected to a low-level periodic (5 Hz) impacting force akin to gentle finger tapping.

Template-Assisted Hydrothermal Growth of Aligned Zinc Oxide Nanowires for Piezoelectric Energy Harvesting Applications.

A flexible and robust piezoelectric nanogenerator (NG) based on a polymer-ceramic nanocomposite structure has been successfully fabricated via a cost-effective and scalable template-assisted hydrothermal synthesis method. Vertically aligned arrays of dense and uniform zinc oxide (ZnO) nanowires (NWs) with high aspect ratio (diameter ∼250 nm, length ∼12 μm) were grown within nanoporous polycarbonate (PC) templates. The energy conversion efficiency was found to be ∼4.