Charge target collection from different triboelectrification domains by electrostatic induction and polarization enabled air discharges†

Abstract

Collecting interfacial tribo-charges is the core of efficient energy conversion in DC triboelectric nanogenerators (DC-TENGs), which is currently realized by electrostatic induction enabled discharges (EID) on side electrodes from nearby tribo-charges. However, the charge collection efficiency is hindered by insufficient collection inside the tribo-layer and non-directional discharges. Herein, different from the traditional DC-TENGs with two electrodes on the sides of the slider, two new dynamic electrodes are positioned below the thick dielectric substrate with a small air gap and move synchronously with the slider. A strong electric field established in the gap causes dynamic dielectric polarization enabled discharges (DPD) on the bottom electrodes, realizing the collection of tribo-charges inside the interface and regulating harmful discharge near the EID. Consequently, the tribo-charges from different triboelectrification domains are fully harvested in target channels, by which the output energy of this charge target collection TENG (CTC-TENG) is increased to 3.85 mJ (EID + DPD) from 0.7 (DPD) and 1.89 mJ (EID), demonstrating a synergistic effect where 1 + 1 > 2. Additionally, the CTC-TENG is utilized for wireless position sensing and energy supply. This work provides important insights into the triboelectrification domains and finds an innovative way for tribo-charge target collection to achieve high output energy.