A Novel Design Based on Mechanical Time-Delay Switch and Charge Space Accumulation for High Output Performance Direct-Current Triboelectric Nanogenerator

Triboelectric nanogenerator (TENG), which converts mechanical energy into electrical energy, has become a promising environment energy harvesting technology. However, traditional TENG, based on the coupling of contact electrification and electrostatic induction, generates alternating current (AC) directly, which requires a rectifier to obtain direct current (DC) before being used to drive electronics. There are a few methods to obtain DC output including mechanical rectifier, phase coupling, air breakdown, and Schottky contact. But to achieve high output and high durability of DC-TENG, new exploration is desired. In this study, a novel DC-TENG is proposed, which greatly improves the output performance by designing a mechanical time-delay switch and an alternative blank-tribo-area. The working mechanism of the DC-TENG is analyzed theoretically and verified by experiments. It is found that the blank-tribo-area promotes charge accumulation, while the mechanical time-delay switch realizes DC output. This DC-TENG can light up 1888 LEDs in series at 60 rpm and drive 24 hygro-thermographs in parallel with 120 rpm. The ultra-high average power density of 4.2 W m(-2) is achieved, much higher than previous works. The DC-TENG displays high durability and retains 92% initial output after 120 000 cycles. This st provides a feasible strategy to boost the output performance of DC-TENG.

Automated summary

A novel DC-TENG is proposed in this study, which greatly improves the output performance and achieves high durability by designing a mechanical time-delay switch and an alternative blank-tribo-area. This study provides a feasible strategy to boost the output performance of DC-TENG.