High-Output and Bending-Tolerant Triboelectric Nanogenerator Based on an Interlocked Array of Surface-Functionalized Indium Tin Oxide Nanohelixes

We present a high-performance flexible triboelectric nanogenerator (TENG) based on an interlocked array of surface-functionalized indium tin oxide (ITO) nanohelix (NH) structures. The structural properties of ITO NHs, including a high nanoscale roughness and unique spring-like geometry, provide a large surface area for an effective friction, enhanced tolerance to bending strain, and operational reliability. The TENG device with surface-functionalized ITO NHs exhibits a significantly enhanced (over 340 times) electrical output power compared to the TENG based on plane ITO. This is attributed to the effective generation of static charges on the large functionalized surface area as well as the efficient charge induction in the ITO electrodes with a unique geometry. We believe that our approach simultaneously overcomes the limitations of available dielectric materials and their low conductivity and reliability and thus can pave the way for the development of portable and wearable self-powered electronic devices.