ZnO nanowire interfaces for high strength multifunctional composites with embedded energy harvesting

Continuous power generation from energy harvesting systems is dependent on their mechanical strength as they convert wasted mechanical energy into useful electrical energy. Here, the first generation of high strength, fiber-based energy harvesters is developed through a simple, scalable and cost-effective process. To fabricate these light yet robust energy harvesting materials, vertically aligned ZnO nanowires are grown on the fibers' surface of a woven aramid fabric. The ZnO nanostructured interface is used as a functional unit as well as a reinforcement component. The power harvesting performance of these hybrid composites is demonstrated through direct vibration examination of a fabricated cantilever beam. The fabricated hybrid composite energy harvester beam produced a high open circuit voltage of similar to 125 mV root mean square (and similar to 0.4 V peak-to-peak) when subjected to a cyclic base acceleration of only 1g root mean square. Moreover, assessing the structural performance of these composites revealed significant increase in the elastic modulus and tensile strength of the composites by 34.3% and 18.4%, respectively. These results indicate that integrating ZnO nanowire arrays not only provides energy harvesting capability, but also enhances the mechanical properties of the composite. This methodology can be considered as the first development of a high strength material with embedded energy harvesting and thus demonstrates multifunctional materials with improved strength and functionality.