Fig. 2: Energy transduction mechanism in the TONE by acoustic-structural-triboelectric interaction.

a, b FEA prediction of acoustic-structural interaction in the TONE. Change of structural shape (a) and von Mises stress distribution (b) by sound pressure. c Schematic illustration of the structural-triboelectric interaction in the TONE. d, e Output voltage (d) and current (e) of the TONE by a controlled sound wave with a sound pressure level of 110 dB and a frequency of 72 Hz. f Fast Fourier transform result of (d).