By converting the biomechanical energy into electricity, the TENG produces an open-circuit voltage up to 1000 V, a short-circuit current density of 8 mA/m2, and a power density of 500 mW/m2 on a load resistance of 100MΩ, which can be used to directly light up tens of green LEDs. Moreover, the fabricated TENGs have been used to design an independently addressable matrix for monitoring the localized touching actions of human skin.
The matrix exhibits both transparent and flexible characteristics, where each pixel can have a size of 3 mm x 3 mm. The tactile information including the position and pressure can be determined by analysis of the realtime recording of positive output voltage signals in the matrix as a mapping figure.
The detection sensitivity of the pressure is about 0.29 ± 0.02 V/kPa. The size of each sensor unit can be significantly reduced so that the spatial resolution can be largely improved.
This work pushes forward a significant step toward the practical applications of skin-based biomechanical energy harvesting techniques and self-powered touchpad technology.