Laminated Triboelectric Nanogenerator for Enhanced Self-Powered Pressure-Sensing Performance by Charge Regulation

Triboelectric sensors provide an effective approach to solving the power supply problem for distributed sensing nodes. However, the poor stability and repeatability of the output signal limit its further development due to structural deficiencies and intrinsic working mechanisms. This work proposes a contact-separation mode laminated triboelectric nanogenerator (L-TENG) by introducing multifunctional layers to regulate triboelectric charges. A liquid metal Galinstan and PDMS mixture with a dense microstructure array is fabricated as the dielectric layer. Liquid squalene is filled in the space between two triboelectric layers to eliminate the influence of moisture in the air. A Cu shield film is sputtered on the surface to screen the electrostatic interference and enhance the repeatability. Owing to the effective design, the sensitivity of the L-TENG could reach 6.66 kPa^-1 in the low-pressure region and 0.79 kPa^-1 in the high-pressure region with a wide detection range from 8 Pa to 71.85 kPa. In addition, it also illustrates fast response and recovery times of 30 and 10 ms, respectively, and great stability in a humid environment. Finally, the L-TENG has been successfully demonstrated to monitor various physical activities in humans such as swallowing, finger bending, and so forth. This work has important scientific significance in opening up a new strategy for the structure optimization and performance improvement of triboelectric sensors.