Triboelectric nanogenerator (TENG) is an emerging technology for converting mechanical energy to electricity. Inspired by the simple configuration, more material choices and specific output, diverse demonstrations of TENG have been proposed over last decade. However, conventional fabrication methods of TENG extremely limit its miniaturization and integration level. Currently, the vast majority of TENG-based acoustic sensors are handcrafted, leading to issues of huge variation, bulky size and instable output. Acoustic energy transfer (AET) for powering implanted devices usually requires the frequency in the ultrasonic range. Most ultrasonic transducers have the best performance when working at resonance mode. Since all the reported TASs are membrane-based, the device sizes approached sub-millimeter when resonant frequency goes to ultrasonic range. As a result, conventional fabrication methods can hardly meet the requirements.
Recently, the research group of Prof. Xuhui Sun, collaborated with Prof. John T.W. Yeow (University of Waterloo), reported a microstructured triboelectric ultrasonic device (µTUD) based on the coupling technologies of TENG and MEMS. This is the very first time that TENG has been fabricated by MEMS process and brought into the microscale. The working frequency of the µTUD is 1.17 MHz, which is toward ultrasonic range without precedent. Moreover, AET through oil and sound-attenuation medium were demonstrated and 16.8 mV and 12.7 mV output voltage were achieved respectively. Pulse experiments were also carried out and a signal-to-noise ratio (SNR) of 20.54 dB was achieved, indicating that the signals can even be modulated from the transmitting end.
The first author, Dr. Chen Chen, is from FUNSOM, Soochow University.
Link to Paper: https://doi.org/10.1038/s41467-020-17842-w
Link to Prof. Sun’s Group: http://funsom.suda.edu.cn/funsomen/c4/a0/c3002a50336/page.htm
Editor: Danting Xiang