Adding a stretchable deep-trap interlayer for high-performance stretchable triboelectric nanogenerators

The main approach to enhancing the electrical output performance of triboelectric nanogenerators (TENGs) has been focused to increase of triboelectric charge generation. However, there have been few studies on achieving effective electrostatic induction and conserving the triboelectric charges. This study reports that an interlayer containing deep charge traps of large trap density can conserve the surface charges for long period of time and increase the surface potential that can be obtained. This study suggests polydimethylsiloxane (PDMS) added between a charge generation layer and an electrode as an effective material candidate for the interlayer. The PDMS interlayer greatly enhanced the output power density of TENGs (20.8 W/m(2) by gentle tapping), which is 173-fold increase compared to TENGs without the interlayer. Surprisingly, the PDMS interlayer resulted in triboelectric performance even between identical surfaces, which is owing to the enhanced charge conservation by the interlayer. This study demonstrates a high-performance stretchable single-electrode TENG (S-TENG) which shows stable high performance at 50% uniaxial strain during repeated stretch cycles. The results in this study provide insight to material design for achieving high-performance stretchable self-powered electronic systems.