Raising the Working Temperature of a Triboelectric Nanogenerator by Quenching Down Electron Thermionic Emission in Contact‐Electrification

• Published in: Advanced materials (Weinheim) Vol. 30; no. 38; pp. e1803968 - n/a
• Main Authors: Xu, Cheng, Wang, Aurelia Chi, Zou, Haiyang, Zhang, Binbin, Zhang, Chunli, Zi, Yunlong, Pan, Lun, Wang, Peihong, Feng, Peizhong, Lin, Zhiqun, Wang, Zhong Lin
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.09.2018
• Subjects: atomic thermal vibration; contact‐electrification; Electric power generation; Electrification; Electrons; Emission analysis; High temperature environments; Materials science; Nanogenerators; Rotation; Silicon dioxide; Temperature dependence; Temperature effects; Thermionic emission; triboelectrification; thermionic emission; contact-electrification; triboelectrification; atomic thermal vibration; nanogenerators
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.201803968

As previously demonstrated, contact‐electrification (CE) is strongly dependent on temperature, however the highest temperature in which a triboelectric nanogenerator (TENG) can still function is unknown. Here, by designing and preparing a rotating free‐standing mode Ti/SiO2 TENG, the relationship between CE and temperature is revealed. It is found that the dominant deterring factor of CE at high temperatures is the electron thermionic emission. Although it is normally difficult for CE to occur at temperatures higher than 583 K, the working temperature of the rotating TENG can be raised to 673 K when thermionic emission is prevented by direct physical contact of the two materials via preannealing. The surface states model is proposed for explaining the experimental phenomenon. Moreover, the developed electron cloud‐potential well model accounts for the CE mechanism with temperature effects for all types of materials. The model indicates that besides thermionic emission of electrons, the atomic thermal vibration also influences CE. This study is fundamentally important for understanding triboelectrification, which will impact the design and improve the TENG for practical applications in a high temperature environment. The relationship between contact electrification (CE) and temperature is revealed by designing and preparing a rotating free‐standing mode Ti/SiO2 triboelectric nanogenerator. The dominant deterring factor of CE at high temperatures is the electron thermionic emission. A developed electron cloud–potential well model accounts for the CE mechanism with temperature effects for all types of materials.