Three-dimensional chiral networks of triboelectric nanogenerators inspired by metamaterial's structure

Abstract

Clusters of machinery units coupled tightly may emerge collective behavior and act like the metamaterial to tackle agitations from the environment. It is especially meaningful for exploiting water wave energy, which is a promising clean energy source with enormous reserves but a formidable challenge for traditional bulky generators. Here, a novel three-dimensional (3D) chiral network of triboelectric nanogenerators (TENGs) is designed for the first time to effectively harvest water wave energy based on this idea. Unlike traditional bulky and rigid machines, the 3D TENG network adopts a distributed architecture with chiral connections between unbalanced units, which imparts the network flexibility, hyper-elasticity in water, and wave-absorption behavior, similar to mechanical chiral metamaterials. The network can be configured to different scales and depths to harvest wave energy in all directions. A comprehensive energy harvesting system integrated with a power management circuit is constructed, with the stored energy enhanced by about 319 times. The novel 3D chiral network shows great potential for blue energy harvesting and self-powered systems based on TENGs, which can be more adaptive to severe ocean environments with flexible and distributed characteristics. This study also presents an insightful paradigm shift from mechanical metamaterial designs to energy harvesting networks, with similarities in mechanical wave energy absorption and conversion, inspiring novel energy harvesting systems and other strongly coupled machinery systems of multiple units based on metamaterials.