Large Harvested Energy by Self-excited Liquid Suspension Triboelectric Nanogenerator with Optimized Charge Transportation Behavior.

To enhance the durability of triboelectric nanogenerator (TENG), liquid lubrication has been used to reduce mechanical abrasion. However, as the charge transportation behavior in dielectric liquid is not clearly understood, the output energy is still low although some improvements have been reported. Herein, we systematically investigate the charge transportation behaviors in dielectric liquid by self-excited liquid suspension triboelectric nanogenerator (LS-TENG). We find the important role of solid-liquid triboelectrification effect, charge-liquid transmission and dissipation effect, and the homogeneous dielectric induction effect in promoting its output performance. The LS-TENG with a dual dielectric tribolayer has advantages of slight driving force and long lifetime for harvesting micro energy. The output of LS-TENG remains almost constant for more than 234 k operating cycles. A high charge density of 704 μC m -2 is obtained, 2.7 times as much as that of current highest record in non-contact TENG. Additionally, the rotary LS-TENG lights up 4,200 LEDs and continuously powers a variety of wireless sensors by harvesting wind energy at low wind speed. This work provides an important insight towards the charge transportation mechanism in dielectric liquid, and a prospective strategy for achieving high robust TENG in micro energy harvesting for practical applications. This article is protected by copyright. All rights reserved.