Fiber‐type piezoelectric nanogenerator devices consisting of radially aligned perovskite PbTiO3 nanotubes have been developed for energy harvesting from arbitrary mechanical motion (see figure below). The free‐standing fiber‐type nanogenerators generate a constant amount of electric power by bending or from wind motion regardless of direction, thus, extending the possibility of their practical applications.
Ki-Seok An and colleagues from the Korea Research Institute of Chemical Technology (KRICT), in Daejeon, Korea, Chonbuk National University, Korea, and Ubon Ratchathani University, Thailand, report in Advanced Materials how the PbTiO3 nanotubes (PTO NTs) can be synthesized by anodic oxidation and employing a hydrothermal method using TiO2 NT as a positive template.
The technique allows the synthesis of flexible, dense, and radially aligned perovskite PTO NTs, with flexible Ti fibers as the core electrode connecting the individual piezoelectric nanotubes. Mass production of the arrays is possible with easy control of diameter, length, and shape of the base materials for different applications. The use of other perovskite materials involving various A‐site elements such as Ba, Bi, Na, K, Sr, Nb, or La is also possible. A device based on the PTO-NTs exhibited impressive values of output voltage and current density of 620 mV and 1.0 nA cm during periodic concave and convex bending motions.
