Rational design of materials and multilayered structures in triboelectric nanogenerators to enhance energy-harvesting efficiency

The exploration of multilayer systems in triboelectric nanogenerators (TENGs) has gained significant attention owing to their advantage in converting mechanical energy from the environment into electrical energy through the synergistic effect between the triboelectric layers. Herein, we report an effective strategy to develop a polydimethylsiloxane (PDMS)-based multilayer TENG to boost the triboelectric efficiency and enhance the triboelectric power output of this system. In addition, we developed ZnSnO₃ decorated on surface-modified multi-walled carbon nanotubes (ZTO@SMC) as an effective filler to further enhance the triboelectric performance. To enhance the synergistic effect between the triboelectric layers, ZTO@SMC and BaTiO₃ were alternately applied as triboelectric layers, which increased the effective dielectric constant and promoted charge redistribution at the interfaces between triboelectric layers. The multilayered TENG structure exhibited output voltage and current outputs of 797 V and 65 μA, respectively, demonstrating excellent a TENG performance. The experimental results combined with computational simulations suggest that the multilayered TENG strengthened the electric field and facilitated charge induction, thereby enhancing the triboelectric energy conversion. Based on these results, we discuss strategies for maximizing the power output of multilayered TENGs, focusing on the filler materials, structural configuration, and triboelectric mechanism arising from their combination.