Liquid-solid triboelectric nanogenerator for bubbles real-time detecting

The bubbles generated in water of lake or sea have a negative effect on organism, ecosystems and underwater equipment. However, bubbles have the characteristics of random distribution and irregular dynamic changes in flow status, making it difficult to detect them. Hence, intelligent devices are urgent needed to monitor these water environments. Triboelectric nanogenerator (TENG) opens up a possibility to solve these problems. In this study, a bubble detecting triboelectric nanogenerator (BD-TENG) based on polyamide 12 (PA12) was fabricated to qualitatively measure the content of bubbles in tubes. A series of peak open-circuit voltage (Voc) of approximately 26 V were appeared when bubbles are presented in great quantity, while that of a stable value around 9 Vat no bubbles state. Additionally, the effect of fluid velocity, bubble volume, generating materials and bubble injection rate was systematically studied. Finally, the performance of CO2 bubble detection of BD-TENG was examined in a mimic water environment, and the Fast Fourier transform (FFT) method are used to make the measured data much more intuitive. This study may provide an effective approach for detecting bubbles.