Tough Nano‐Architectured Conductive Textile Made by Capillary Splicing of Carbon Nanotubes

Abstract

Flexible electronics require electrically conductive and mechanically reliable nanoscale thin films. However, thin metal films have low fracture energy, which limits the performance of flexible devices. We demonstrate the design and synthesis of highly conductive, strong and tough nano-architectured textile by capillary splicing of aligned carbon nanotubes (CNT). Owing to the strong van der Waals forces among CNTs, the pristine CNT network has average strength of 170 MPa. The average fracture energy of the textile is 16 kJ/m 2 , 50 folds higher than metal nanofilms. The high toughness results from crack bifurcations and friction hysteresis in a dissipation zone propagating several millimeters ahead of the crack tip. This material is suitable for applications ranging from smart skin and flexible sensors.

Carbon Nanotubes and Related Nanomaterials: Critical Advances and Challenges for Synthesis toward Mainstream Commercial Applications

“…In recent years, CNT forests have been shown to be advantageous for supercapacitor electrodes, 108−110 electronic interconnects for vertical vias, 111−114 electron emitters, 115,116 broadband optical absorbers, 117 terahertz technologies (generators, 118 polarizers, 119 detectors 120 ), optical rectennas, 121 thermopower wave guides, 122 thermal interface materials, 123−125 anisotropic surfaces, 126 gecko-inspired dry adhesives, 127 flexographic printing, 128 mechanical dampers, 129,130 selective membrane nanochannels, 131−133 and advanced yarns and sheets. 134,135 Aside from pure applications, CNT forests are heavily studied because they are model systems for analyzing growth kinetics, wherein the average collective height of the forest is related to the length of individual constituent CNTs. 136,137 To make CNT forests competitive in each application space, targeted growth must advance to hone application-specific properties.…”

Nature-Inspired Structural Materials for Flexible Electronic Devices

“…262,263 Moreover, conductive films with other mechanical behaviors, including high strength and toughness, can also be realized by capillary splicing of aligned carbon nanotubes into nano-architecture textiles. 264 Beyond various networks formed by interconnected 1D conductors on elastic substrates, natural network systems can also provide inspiration and directly participate in fabrication towards the achievement of highly stretchable electrodes. 202,203 For example, leaf venation constitutes a network structure for the efficient delivery of nutrients in leaves under low lighting.…”

Bottom-Up Synthesis and Mechanical Behavior of Refractory Coatings Made of Carbon Nanotube-Hafnium Diboride Composites

“…The conformal HfB 2 coating process uses static (S-) CVD, where the precursor is fed into a closed system enabling highly conformal coating and economically efficient utilization of the HfB 2 precursor reaching 85%. Advantages of using CNT forests as the template are their large surface area, their millimeter heights, and the ability to control their 3D architectures. , Such thick films of HfB 2 would otherwise not be accessible to any thin-film CVD process, which only deposits nanometer-thin films. Owing to the highly conformal HfB 2 deposition, a network of cross-links reinforces the nodes because of coating.…”

“…Advantages of using CNT forests as the template are their large surface area, their millimeter heights, and the ability to control their 3D architectures. 7,8 Such thick films of HfB 2 would otherwise not be accessible to any thin-film CVD process, which only deposits nanometer-thin films. Owing to the highly conformal HfB 2 deposition, a network of cross-links reinforces the nodes because of coating.…”