A Single Integrated 3D-Printing Process Customizes Elastic and Sustainable Triboelectric Nanogenerators for Wearable Electronics

Triboelectric nanogenerator (TENG) devices have gotten great attention in wearable power sources and physiological monitoring. However, the complicated assembling and the molding processing retard their applications. Here, 3D-printed TENGs (3DP-TENGs) are designed and readily fabricated by a single integrated process without additional assembling steps. The TENGs contain poly(glycerol sebacate) (PGS) and carbon nanotubes (CNTs) as the two electrification components. Conductive CNTs also serve as electrodes. Elastic PGS matrix makes TENGs intrinsically responsive to biomechanical motions leading to robust energy outputs. The hierarchical porous structure of the 3DP-TENG results in higher output efficiency than traditional molded microporous TENG counterparts. TENGs with different 3D shapes are readily fabricated for different applications. The 3DP-TENG insole efficiently harvests biomechanical energy to drive electronics. A ring-shaped TENG acts as a self-powered sensor to monitor the motion of fingers. Furthermore, the use of bio-based and biodegradable PGS matrix combining with efficient recycle of CNTs makes 3DP-TENGs favorable from sustainable perspective. This work provides a new strategy to design and tailor 3D TENGs that will be very useful for diverse electronic applications.