A triboelectric nanogenerator sensor based on phononic crystal structures for smart buildings and transportation systems

Many buildings and equipment are frequently disturbed by various types of elastic wave or vibration sources in ambient environment. The real-time state monitoring of such a disturbance is very important in the fields of green buildings and intelligent transportation systems. Based on triboelectric nanogenerators (TENGs), we propose a two-dimensional phononic crystal TENG (PC-TENG), which can serve as a self-powered sensor. The PCTENG system consists of a periodical spherical cavity type of plate-like structure and elastic balls placed in each spherical cavity. Particularly, with bandgap property of phononic crystals, the proposed PC-TENG can also absorb or suppress vibration impact with certain frequencies acting on buildings and equipment. Taking elasticity, diameter, and surface roughness of elastic ball into account, we established a theoretical model of the cavity-ball type of PC-TENG based on Hertzian contact model. The sensing performance of the proposed PCTENG with 5 by 5 cavities are experimentally measured, which shows the PC-TENG can efficiently detect the amplitude and frequency of an elastic wave disturbance. The theoretical output charges and currents evaluated from the developed theoretical model agree well with the experimental data.

Automated summary

In this paper, a two-dimensional phononic crystal sensor based on triboelectric nanogenerators is proposed for real-time monitoring of elastic wave disturbances on buildings and equipment. The sensor can also absorb or suppress vibrations with specific frequencies.