Boosting output performance of sliding mode triboelectric nanogenerator by charge space-accumulation effect

Abstract

The sliding mode triboelectric nanogenerator (S-TENG) is an effective technology for in-plane low-frequency mechanical energy harvesting. However, as surface modification of tribo-materials and charge excitation strategies are not well applicable for this mode, output performance promotion of S-TENG has no breakthrough recently. Herein, we propose a new strategy by designing shielding layer and alternative blank-tribo-area enabled charge space-accumulation (CSA) for enormously improving the charge density of S-TENG. It is found that the shielding layer prevents the air breakdown on the interface of tribo-layers effectively and the blank-tribo-area with charge dissipation on its surface of tribo-material promotes charge accumulation. The charge space-accumulation mechanism is analyzed theoretically and verified by experiments. The charge density of CSA-S-TENG achieves a 2.3 fold enhancement (1.63 mC m−2) of normal S-TENG in ambient conditions. This work provides a deep understanding of the working mechanism of S-TENG and an effective strategy for promoting its output performance.

Simultaneously Enhancing Power Density and Durability of Sliding‐Mode Triboelectric Nanogenerator via Interface Liquid Lubrication

“…[ 30 ] Moreover, the maximum power density after adding liquid lubricant increases from 1.24 to 3.45 W m −2 Hz −1 (peak power from 21.7 to 32.9 mW), which is three times compared to previous report rotary sliding FS‐TENG with shielding layer and alternative blank triboarea. [ 20 ] Additionally, the suppression effect of liquid lubricant on electrostatic breakdown is proved once again by comparing the breakdown effect on the complementary electrode under open circuit condition, where obvious breakdown phenomenon arises in the normal device, while no breakdown can be found in the lubricated electrode (Movie S2, Supporting Information). It is worth noting that, the electric stability of rotary sliding TENG was also investigated for more than 100 000 operation cycles.…”

“…[ 18,19 ] Nevertheless, strict environment requirement and severe abrasion problem make them unsuitable from the point of application view. Very recently, shielding layer and alternative blank triboarea was reported to improve the output power density of sliding‐mode AC‐TENG with value of 1.15 W m −2 Hz −1 , [ 20 ] where air breakdown on the interface of tribolayers was effectively constrained. However, this strategy is not well applicable for enhancing output performance of sliding‐mode DC‐TENG, and a violent friction during sliding process always generate abrasion, thus causing poor durability of TENG.…”

“…Finally, the maximum output power density of 3.45 W m −2 Hz −1 is achieved for lubricating rotary sliding‐mode TENG, which is increased to three times of that reported previously. [ 20 ] Furthermore, a sliding‐mode TENG exhibits superior output durability after more than 500 000 operation cycles. This work demonstrates the capability of interface liquid lubrication for enhancing power density and durability for both sliding‐mode AC‐TENG and sliding‐mode DC‐TENG, which can significantly push the practical applications of TENG.…”

Triboelectric nanogenerator: from alternating current to direct current

“…As the world is entering the era of internet of things (IoTs), sensor networks, big data, robotics, and artificial intelligence, its sensors are mobile and ubiquitous, and its electronic devices are following a general trend of miniaturization, portability, and functionality ( Wang, 2019 ). Based on TE effect and electrostatic induction, triboelectric nanogenerator (TENG) was first invented by Wang's Group in 2012 ( Fan et al., 2012 ), and it has attracted significant attention as an emerging mechanical energy harvesting technology owing to its various merits of simple structure, light weight, diverse choice of materials, low cost, and high efficiency even at low frequency ( He et al., 2020 ; Lin et al., 2013 ; Luo et al., 2019 ; Peng et al., 2019 , 2020 ; Song et al., 2019 ; Xiong et al., 2020 ; Yang et al., 2019 ; Zhang et al., 2018a , 2018b ; Zhu et al., 2014b ). Generally, the output of TENG is AC pulse feature, which must be converted to a DC output or even a constant current output across the power management circuit for powering electronics ( Harmon et al., 2020 ; Niu et al., 2015 ; Qin et al., 2018 ; Xi et al., 2017 ; Xu et al., 2019b ; Zhang et al., 2020b ).…”

Understanding the Percolation Effect in Triboelectric Nanogenerator with Conductive Intermediate Layer

“…However, a major challenge of the TENG is the relatively low surface charge density that limits the output performance and potential applications [ 11 – 15 ]. Many efforts have been made to improve the surface charge density, such as material selection [ 12 ], surface charge injection [ 13 ], tribomaterial surface modification [ 14 – 17 ], intermediate layer integration [ 18 ], external-charge pumping [ 19 ], and self-charge excitation [ 20 , 21 ]. Among these methods, embedding conductive intermediate layer into TENG provides an efficient, cost-friendly, and scalable pathway to improve the surface charge density and output performance [ 18 ].…”