A stretchable carbon nanotube strain sensor for human-motion detection

TL;DR: Not only is an effective strategy for screening of sensor sensitivity demonstrated, but a contribution to the mechanocombinatorial strategy for personalized stretchable electronics is also made.

TL;DR: In this paper, the authors studied the strain sensing behavior of multi-walled carbon nanotubes (MWCNT)/epoxy (EP) conductive composites subjected to tensile strain.

TL;DR: In this paper, a new type of highly stretchable and reliable supercapacitor is developed based on crumpled vertically aligned carbon nanotube (CNT) forests transferred onto an elastomer substrate with the assistance of a thermal annealing process in atmosphere environment.

Abstract: Wearable and skin‐mountable strain sensors are highly demanding for monitoring skin deformations induced by human activities. Realization of such sensor devices based on fiber‐optic approaches offers attractive advantages such as electromagnetic immunity and inherent electric safety in comparison to their electronic counterparts. However, fiber‐optic sensors, conventionally made of stiff silica fibers, are not mechanically compliant with the soft human skins and have limited strain range (<1%) for measuring large deformations. Here, a stretchable fiber Bragg grating (FBG)‐based optical (SFO) strain sensor with skin‐like compliance for human activity monitoring is presented. The SFO sensor is fabricated by a sinuous‐shaped FBG incorporated with a stretchable substrate that responds to strain deformations by shifting of the Bragg wavelength. This structural design enables measurement of various dynamic strains associated with tension, bending and torsion in a large sensing range up to 50%. To facilitate wearable integrations, a novel free‐running fiber laser with coherent dual‐comb output is developed to interrogate the SFO sensors by dual‐comb spectroscopy, which enables fast spectral acquisition with a single photodiode. It is shown that the SFO strain sensors can be used for wearable and skin‐mountable detection of diverse human activities including breathing, phonation, facial expression, and joint movements in real time.

TL;DR: Water-stimulated enhanced catalytic activity results in massive growth of superdense and vertically aligned nanotube forests with heights up to 2.5 millimeters that can be easily separated from the catalysts, providing nanotubes material with carbon purity above 99.98%.

TL;DR: This dense carbon-nanotube material is advantageous for numerous applications, and here it is demonstrated its use as flexible heaters as well as supercapacitor electrodes for compact energy-storage devices.

TL;DR: The manufacture of printable elastic conductors comprising single-walled carbon nanotubes (SWNTs) uniformly dispersed in a fluorinated rubber is described, which is constructed a rubber-like stretchable active-matrix display comprising integrated printed elastic conductor, organic transistors and organic light-emitting diodes.

TL;DR: A simple approach to high-performance, stretchable, and foldable integrated circuits that integrate inorganic electronic materials, including aligned arrays of nanoribbons of single crystalline silicon, with ultrathin plastic and elastomeric substrates.