Triboelectric nanogenerator with enhanced output and durability based on Si-DLC films

Abstract

As one of the working modes of triboelectric nanogenerators (TENGs), the sliding-mode TENG has a higher charge-transfer efficiency than the contact-separation mode. However, the durability and stability of these devices remain challenging for practical applications because most dielectric materials for TENGs are organic polymers. This study used Si-incorporated diamond-like carbon (Si-DLC) films as non-polymer dielectric materials for sliding-TENGs to improve output and durability. Si-DLC films with varying Si contents were prepared using plasma-based ion implantation and deposition, and their triboelectric and tribological properties were investigated. The Si-DLC film with a higher Si content exhibited a higher triboelectric output under dry conditions owing to its stronger electron-donating ability. Furthermore, it was found that the output and durability of the Si-DLC-based sliding-TENG can be further enhanced under unsubmerged water-lubricated conditions compared with those under dry conditions. This enhanced output is attributed to the more electropositive nature of water compared with that of the Si-DLC films. Moreover, the enhanced durability and stability of the Si-DLC-based TENG under water-lubricated conditions are attributed to the anti-abrasion properties of the Si-DLC films, which prevent the formation of a transferred PTFE layer on the Si-DLC surface. This research proposed an integrated strategy to enhance output and durability simultaneously, showing great potential for designing durable self-driving sensing systems in machinery.