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Indexed by:Journal Papers

Date of Publication:2019-12-01

Journal:CARBON

Included Journals:EI、SCIE

Volume:155

Page Number:421-431

ISSN No.:0008-6223

Key Words:Strain sensor; Carbon nanotube network; Percolation theory; Tunneling effect; Tuning density

Abstract:Transparent, highly stretchable and sensitive strain sensors have been successfully fabricated using carbon nanotube (CNT) networks with various densities as the sensing medium. Owing to the unique two-dimensional percolated structure, the CNT network-based sensors exhibit excellent sensing performance over a wide strain range from 0.5 to 100%. By decreasing the density of CNTs from 152 to 7.2/mu m(2), their gauge factor is remarkably increased from 0.4 to 50. It is found from the experimental results and theoretical analysis that the sensing mechanism of the CNT networks is transferred from percolation theory to tunneling effect with decreasing the density or increasing the tensile strain of the CNT networks. This study provides a facile technique to prepare high stretchable strain sensors and also fundamental principles for the structural design of the CNT network-based strain sensors. (C) 2019 Elsevier Ltd. All rights reserved.