Electromechanical coupling of isotropic fibrous networks with tailored auxetic behavior induced by water-printing under tension. Issue 13 (19th March 2021)

• Record Type: Journal Article
• Authors: Zhang, Jinyuan; Goodman, Sheila M.; Wise, Heather G.; Dichiara, Anthony B.; Chung, Jae-Hyun
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 13(2021)
• Page Start: 4544
• Page End: 4553
• Publication Date: 2021-03-19
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d0tc05526c
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : A wetting–stretching method is presented to enhance the auxeticity and piezoresistivity of a random network made of a carbon nanotube-paper composite. Abstract : Understanding the electromechanical coupling of auxetic materials offers unique opportunities to enhance the sensitivity of piezoresistive sensors. Reports on the auxetic behavior of random fiber networks have been relatively scarce due to their less pronounced Poisson's expansions than other auxetic designs adapting periodically arranged structures. In this study, the auxetic response of hierarchical pulp-carbon nanotube networks is tailored through the localized tensional micro-fracture initiated by water-printing. The interfacial junctions among multiwalled carbon nanotubes (MWCNTs) and cellulose fibers are disintegrated and reorganized to induce the buckling of a wet CNT paper composite (CPC) network. The Poisson's ratio of −49.5 is achieved at the water-printed region. The resulting piezoresistive properties of CPC sensors exhibit high sensitivity (3.3 kPa −1 ) over a wide dynamic range (6–500 000 Pa). The novel auxetic behavior of water-printed CPC paves the way for high performance and inexpensive wearable devices.