TY - JOUR
T1 - Contact-electrification between two identical materials
T2 - Curvature effect
AU - Xu, Cheng
AU - Zhang, Binbin
AU - Wang, Aurelia Chi
AU - Zou, Haiyang
AU - Liu, Guanlin
AU - Ding, Wenbo
AU - Wu, Changsheng
AU - Ma, Ming
AU - Feng, Peizhong
AU - Lin, Zhiqun
AU - Wang, Zhong Lin
N1 - Funding Information:
The authors are grateful for the support received from Hightower Chair Foundation. C.X. thanks the Outstanding Teacher Overseas Research Project of China University of Mining and Technology.
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/2/26
Y1 - 2019/2/26
N2 - It is known that contact-electrification (or triboelectrification) usually occurs between two different materials, which could be explained by several models for different materials systems (Adv. Mater. 2018, 30, 1706790; Adv. Mater. 2018, 30, 1803968). But contact between two pieces of the chemically same material could also result in electrostatic charges, although the charge density is rather low, which is hard to understand from a physics point of view. In this paper, by preparing a contact-separation mode triboelectric nanogenerator using two pieces of an identical material, the direction of charge transfer during contact-electrification is studied regarding its dependence on curvatures of the sample surfaces. For materials such as polytetrafluoroethylene, fluorinated ethylene propylene, Kapton, polyester, and nylon, the positive curvature surfaces are net negatively charged, while the negative curvature surfaces tend to be net positively charged. Further verification of the above-mentioned trends was obtained under vacuum (â1 Pa) and higher temperature (≤358 K) conditions. Based on the received data acquired for gentle contacting cases, we propose a curvature-dependent charge transfer model by introducing curvature-induced energy shifts of the surface states. However, this model is subject to be revised if the mutual contact mode turns into a sliding mode or more complicated hard-pressed contact mode, in which a rigorous contact between the two pieces of the same material could result in nanoscale damage/fracture and possible species transfer. Our study provides a primitive step toward understanding the basics of contact-electrification.
AB - It is known that contact-electrification (or triboelectrification) usually occurs between two different materials, which could be explained by several models for different materials systems (Adv. Mater. 2018, 30, 1706790; Adv. Mater. 2018, 30, 1803968). But contact between two pieces of the chemically same material could also result in electrostatic charges, although the charge density is rather low, which is hard to understand from a physics point of view. In this paper, by preparing a contact-separation mode triboelectric nanogenerator using two pieces of an identical material, the direction of charge transfer during contact-electrification is studied regarding its dependence on curvatures of the sample surfaces. For materials such as polytetrafluoroethylene, fluorinated ethylene propylene, Kapton, polyester, and nylon, the positive curvature surfaces are net negatively charged, while the negative curvature surfaces tend to be net positively charged. Further verification of the above-mentioned trends was obtained under vacuum (â1 Pa) and higher temperature (≤358 K) conditions. Based on the received data acquired for gentle contacting cases, we propose a curvature-dependent charge transfer model by introducing curvature-induced energy shifts of the surface states. However, this model is subject to be revised if the mutual contact mode turns into a sliding mode or more complicated hard-pressed contact mode, in which a rigorous contact between the two pieces of the same material could result in nanoscale damage/fracture and possible species transfer. Our study provides a primitive step toward understanding the basics of contact-electrification.
KW - Contact-electrification
KW - Curvature
KW - Identical material
KW - Surface states
KW - Triboelectric nanogenerator
KW - Triboelectrification
UR - http://www.scopus.com/inward/record.url?scp=85061505340&partnerID=8YFLogxK
U2 - 10.1021/acsnano.8b08533
DO - 10.1021/acsnano.8b08533
M3 - Article
C2 - 30707552
AN - SCOPUS:85061505340
SN - 1936-0851
VL - 13
SP - 2034
EP - 2041
JO - ACS Nano
JF - ACS Nano
IS - 2
ER -