Torsion sensors of high sensitivity and wide dynamic range based on a graphene woven structure

Yang, Tingting; Wang, Yan; Li, Xinming; Zhang, Yangyang; Li, Xiao; Wang, Kunlin; Wu, Dehai; Hu, Jin; Li, Zhihong; Zhu, Hongwei

doi:10.1039/c4nr03252g

Cited by 48 publications

(42 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[1][2][3][4] Especially, promoted by the demand for wearable devices, there is a vigorous and urgent need to develop fl exible and highly sensitive strain sensors based on graphene and other 2D materials. [5][6][7][8][9][10][11] The sensitivity of such strain sensors refl ects the electrical response versus applied strain ( ε ), which is valuable to monitor the slight deformation of target object for broad wileyonlinelibrary.comdegradation of graphene. [ 20 ] Recently, nanographene fi lms have been synthesized and high GFs (up to 600) could be achieved for a <2% strain thanks to the well controls of tunneling passageways.…”

Section: Introductionmentioning

confidence: 99%

Large‐Area Ultrathin Graphene Films by Single‐Step Marangoni Self‐Assembly for Highly Sensitive Strain Sensing Application

Yang

et al. 2016

Adv Funct Materials

Self Cite

350

259

View full text Add to dashboard Cite

1322 wileyonlinelibrary.com applications in fi elds of healthcare monitoring, human-computer interaction, and electronic skin. [ 12 ] The relative resistance Δ R normalized by the initial resistance R 0 depends on Poisson's ratio ( ν ) and resistivity variation (Δ ρ ) normalized by its initial resistivity ρ 0 through the expression ΔR / R 0 = (1 + 2ν) ε + Δ ρ / ρ 0.[ 13 ] The sensitivity revealed by gauge factor (GF, defi ned as ( ΔR / R 0 )/ ε ) depends on both intrinsic property and structural feature. According to this formula, graphene-based strain sensors have shown low sensitivities due to the rigid and stable structure of intrinsic graphene. [ 14 ] With hardly opened band gap, the GF of a suspended graphene is only about 1.9 under moderate uniaxial strains. [ 15 ] Therefore, structural engineering of graphene is needed to boost the sensitivity of graphene-based strain sensors.Adjustment of the connection channels in graphene is an effective way to alter its resistivity for improved sensitivity in strain sensors. Two common methods for the structural construction of graphene include high temperature processing based chemical vapor deposition (CVD) and solution processing based sheets/fl akes assembly. As for CVD, the resistivity of graphene would be affected by its grain boundary, grain size, and the defect density. [16][17][18] Continuous graphene fi lms grown by CVD could sustain 1% strain with a GF of only 6.1, [ 19 ] and the GF increases to 151 for a 5% strain due to the morphological Large-Area Ultrathin Graphene Films by Single-Step Marangoni Self-Assembly for Highly Sensitive Strain Sensing ApplicationXinming Li , Tingting Yang , Yao Yang , Jia Zhu , Li Li , Fakhr E. Alam , Xiao Li , Kunlin Wang , Huanyu Cheng , Cheng-Te Lin , * Ying Fang , * and Hongwei Zhu * Promoted by the demand for wearable devices, graphene has been proved to be a promising material for potential applications in fl exible and highly sensitive strain sensors. However, low sensitivity and complex processing of graphene retard the development toward the practical applications. Here, an environment-friendly and cost-effective method to fabricate large-area ultrathin graphene fi lms is proposed for highly sensitive fl exible strain sensor. The assembled graphene fi lms are derived rapidly at the liquid/air interface by Marangoni effect and the area can be scaled up. These graphene-based strain sensors exhibit extremely high sensitivity with gauge factor of 1037 at 2% strain, which represents the highest value for graphene platelets at this small deformation so far. This simple fabrication for strain sensors with highly sensitive performance of strain sensor makes it a novel approach to applications in electronic skin, wearable sensors, and health monitoring platforms.

show abstract

Section: Introductionmentioning

confidence: 99%

Large‐Area Ultrathin Graphene Films by Single‐Step Marangoni Self‐Assembly for Highly Sensitive Strain Sensing Application

Yang

et al. 2016

Adv Funct Materials

Self Cite

350

259

View full text Add to dashboard Cite

show abstract

“…Because of the increasing demand on wearable and portable electronics as alternatives to conventional rigid appliances, significant interests have been initiated in developing stretchable and deformable devices, such as artificial skin [1], flexible organic field-effect transistor [2], skin-like sensor [3], strain and human motion signal sensor [4,5], stretchable electrode [6] and other conform devices [7,8]. In the development of wearable electronics, the development of stretchable and wearable energy storage devices is still very challenging.…”

Section: Introductionmentioning

confidence: 99%

Dynamically stretchable supercapacitors based on graphene woven fabric electrodes

Zang

Zhu

et al. 2015

Nano Energy

Self Cite

View full text Add to dashboard Cite

“…The complexity of torsion, which causes both normal and shear strain, has previously precluded the development of a simple sensor capable of measuring a large range of torsion. Existing torsion sensors measure changes in normalized resistance, pressure, and optical properties, or utilize surface acoustic waves or the inverse magnetostrictive effect . Some of these sensors can detect changes as small as 0.3 rad m −1 and can measure torsion up to 800 rad m −1 before failure.…”

Section: Introductionmentioning

confidence: 99%

Stretchable Capacitive Sensors of Torsion, Strain, and Touch Using Double Helix Liquid Metal Fibers

Cooper

Arutselvan

Liu

et al. 2017

Adv Funct Materials

300

169

View full text Add to dashboard Cite

1605630(1 of 8) temperature, and low viscosity. The latter property allows LM to flow in response to deformation, whereas solid metals are stiff and prone to fail at small strains. Embedding LM in elastomer decouples the electrical and mechanical properties; that is, these composites have the electrical properties of the metal and the mechanical properties of the elastomer. Incorporating the LM into the hollow core of an elastomeric fiber results in a useful form for sensors because fibers may be integrated into clothing and fabrics. [12][13][14][15] Furthermore, fibers are inherently flexible, compliant, and conformal due to their narrow cross-section. Thus, fibers can readily wrap onto and conform to surfaces with Gaussian curvature whereas 2D sheets cannot without significant deformation. Fibers can also be mass produced at high speeds with small diameters (hundreds of microns) and produced by hand in a laboratory environment at room temperature. [16] The fibers described in this work have the additional advantage of being built from stretchable and soft materials. Fibers with LM cores have previously been used to make light-emitting structures [17] and stretchable wires that retain metallic conductance up to ≈800% strain. [18] We reasoned that elastomeric fibers filled with LM could also be used for capacitive sensing of torsion, strain, and touch.Here, we intertwined two fibers into a double-helix to create sensors of both torsion and strain since twisting or stretching the fibers increases the contact area between them, and therefore changes the capacitance. The complexity of torsion, which causes both normal and shear strain, has previously precluded the development of a simple sensor capable of measuring a large range of torsion. Existing torsion sensors measure changes in normalized resistance, [2,8,19,20] pressure, [9] and optical properties, [21] or utilize surface acoustic waves [22] or the inverse magnetostrictive effect. [23] Some of these sensors can detect changes as small as 0.3 rad m −1 and can measure torsion up to 800 rad m −1 before failure. Most existing torsion sensors, however, are rigid, cumbersome, expensive, and complex. The soft and stretchable sensor developed here offers a simple mechanism to measure large changes in torsion which may be useful for unconventional robotics [24,25] or artificial muscles. [26] In addition to sensing torsion, intertwined fibers increase capacitance in response to strain due to the increase in contact Soft and stretchable sensors have the potential to be incorporated into soft robotics and conformal electronics. Liquid metals represent a promising class of materials for creating these sensors because they can undergo large deformations while retaining electrical continuity. Incorporating liquid metal into hollow elastomeric capillaries results in fibers that can integrate with textiles, comply with complex surfaces, and be mass produced at high speeds. Liquid metal is injected into the core of hollow and extremely stretchable elastomeric fibers and the re...

show abstract

Torsion sensors of high sensitivity and wide dynamic range based on a graphene woven structure

Cited by 48 publications

References 33 publications

Large‐Area Ultrathin Graphene Films by Single‐Step Marangoni Self‐Assembly for Highly Sensitive Strain Sensing Application

Large‐Area Ultrathin Graphene Films by Single‐Step Marangoni Self‐Assembly for Highly Sensitive Strain Sensing Application

Dynamically stretchable supercapacitors based on graphene woven fabric electrodes

Stretchable Capacitive Sensors of Torsion, Strain, and Touch Using Double Helix Liquid Metal Fibers

Contact Info

Product

Resources

About