Nano-Oil-Barrier-Based Fluttering Triboelectric Nanogenerator.

In the field of triboelectric nanogenerators (TENGs), the application of a thin lubricant layer on the contact surface and its maintenance for long-term cycling remain important challenges for improving the mechanical-electrical stability of TENGs. Herein, a simple and innovative approach is proposed to solve this dilemma using commercial oil-absorbing sheets and oil infusion steps. In particular, a wind-driven nano-oil-barrier-based fluttering triboelectric nanogenerator (NF-TENG) is developed. The nano-oil barrier (of nanoscale thickness) of NF-TENG is thoroughly analyzed using atomic force microscopy imaging and electrical-mechanical measurement/calculation results. Compared with other control groups, only NF-TENG maintains 95% output performance from 100% initial output performance, and device damage is minimized even after 970,000 cycles. The mechanism of NF-TENG and its differences from previous studies are established. NF-TENG is optimized and studied for various design variables and wind speeds. NF-TENG generated a peak power of 468 µW with 100 Hz and an average power of 166 µW at optimum load resistance, under a breeze wind speed of 6 m s. NF-TENG demonstrates its applications in two real-life scenarios: 1) wind harvesting at a rooftop vent pipe for outdoor temperature-humidity sensing, and 2) wind harvesting during bicycle riding for safety light illumination.