Electronic and photonic fiber devices that can sustain large elastic deformation are becoming key components in a variety of fields ranging from healthcare to robotics and wearable devices. The ...fabrication of highly elastic and functional fibers remains however challenging, which is limiting their technological developments. Simple and scalable fiber‐processing techniques to continuously codraw different materials within a polymeric structure constitute an ideal platform to realize functional fibers and devices. Despite decades of research however, elastomeric materials with the proper rheological attributes for multimaterial fiber processing cannot be identified. Here, the thermal drawing of hundreds‐of‐meters long multimaterial optical and electronic fibers and devices that can sustain up to 500% elastic deformation is demonstrated. From a rheological and microstructure analysis, thermoplastic elastomers that can be thermally drawn at high viscosities (above 103 Pa s), allowing the encapsulation of a variety of microstructured, soft, and rigid materials are identified. Using this scalable approach, fiber devices combining high performance, extreme elasticity, and unprecedented functionalities, allowing novel applications in smart textiles, robotics, or medical implants, are demonstrated.
Superelastic multimaterial electronic and photonic fibers are fabricated via thermal drawing. Thermoplastic elastomers with the proper rheological properties to be codrawn with a variety of functional materials, including liquid metals and nanocomposites, are identified. This provides a novel approach for the scalable fabrication of advanced stretchable electronic and photonic devices with unprecedented functionalities.
Flexible pressure sensors offer a wide application range in health monitoring and human–machine interaction. However, their implementation in functional textiles and wearable electronics is limited ...because existing devices are usually small, 0D elements, and pressure localization is only achieved through arrays of numerous sensors. Fiber‐based solutions are easier to integrate and electrically address, yet still suffer from limited performance and functionality. An asymmetric cross‐sectional design of compressible multimaterial fibers is demonstrated for the detection, quantification, and localization of kPa‐scale pressures over m2‐size surfaces. The scalable thermal drawing technique is employed to coprocess polymer composite electrodes within a soft thermoplastic elastomer support into long fibers with customizable architectures. Thanks to advanced mechanical analysis, the fiber microstructure can be tailored to respond in a predictable and reversible fashion to different pressure ranges and locations. The functionalization of large, flexible surfaces with the 1D sensors is demonstrated by measuring pressures on a gymnastic mat for the monitoring of body position, posture, and motion.
Compressible and conducting fibers for the measurement of kPa‐scale pressures over m2‐size surfaces are demonstrated. Pressure quantification and localization on the thermally drawn fibers are achieved through the selective and reversible contacting of composite electrodes within a thermoplastic elastomer support at distinct pressure levels. By functionalizing surfaces with the fibers, pressures are assessed for body position, posture, and motion monitoring.
The recent ability to integrate semiconductor‐based optoelectronic functionalities within thin fibers is opening intriguing opportunities for flexible electronics and advanced textiles. The scalable ...integration of high‐quality semiconducting devices within functional fibers however remains a challenge. It is difficult with current strategies to combine high light absorption, good microstructure and efficient electrical contact. The growth of semiconducting nanowires is a great tool to control crystal orientation and ensure a combination of light absorption and charge extraction for efficient photodetection. Thus far, however, leveraging the attributes of nanowires has remained seemingly incompatible with fiber materials, geometry, and processing approaches. Here, the integration of semiconducting nanowire‐based devices at the tip and along the length of polymer fibers is demonstrated for the first time. The scalable thermal drawing process is combined with a simple sonochemical treatment to grow nanowires out of electrically addressed amorphous selenium domains. First principles density‐functional theory calculations show that this approach enables to tailor the surface energy of crystal facets and favors nanowire growth along a preferred orientation, resulting in fiber‐integrated devices of unprecedented performance. This novel platform is exploited to demonstrate an all‐fiber‐integrated fluorescence imaging system, highlighting novel opportunities in sensing, advanced optical probes, and smart textiles.
High‐quality monocrystalline semiconducting nanowire‐based optoelectronic devices, for the first time, are integrated into the tip of a polymer optical fiber and along the fiber length. The fiber‐integrated devices, fabricated via a combination of simple and scalable approaches, exhibit unprecedented optoelectronic properties. The opportunities of this approach in advanced fibers and textiles are highlighted via an all‐fiber‐integrated fluorescence imaging system.
Modern devices require the tuning of the size, shape and spatial arrangement of nano-objects and their assemblies with nanometre-scale precision, over large-area and sometimes soft substrates. Such ...stringent requirements are beyond the reach of conventional lithographic techniques or self-assembly approaches. Here, we show nanoscale control over the fluid instabilities of optical thin glass films for the fabrication of self-assembled all-dielectric optical metasurfaces. We show and model the tailoring of the position, shape and size of nano-objects with feature sizes below 100 nm and with interparticle distances down to 10 nm. This approach can generate optical nanostructures over rigid and soft substrates that are more than tens of centimetres in size, with optical performance and resolution on a par with advanced traditional lithography-based processes. To underline the potential of our approach, which reconciles high-performance optical metasurfaces and simple self-assembly fabrication approaches, we demonstrate experimentally and via numerical simulation sharp Fano resonances with a quality factor, Q, as high as ∼300 in the visible for all-dielectric nanostructures, to realize protein monolayer detection.
Biodegradable polymers are increasingly employed at the heart of therapeutic devices. Particularly in the form of thin and elongated fibers, they offer an effective strategy for controlled release in ...a variety of biomedical configurations such as sutures, scaffolds, wound dressings, surgical or imaging probes, and smart textiles. So far however, the fabrication of fiber‐based drug delivery systems has been unable to fulfill significant requirements of medicated fibers such as multifunctionality, adequate mechanical strength, drug loading capability, and complex release profiles of multiple substances. Here, a novel paradigm in the design and fabrication of microstructured biodegradable fibers with tailored mechanical properties and capable of predefined release patterns from multiple reservoirs is proposed. Different biodegradable polymers compatible with the scalable thermal drawing process are identified, and their release properties as thin films of various thicknesses in the fiber form are experimentally investigated and modeled. Multimaterial microstructured fibers with predictable complex release profiles of potentially different substances are then designed and fabricated. Moreover, the tunability of the mechanical properties via tailoring the drawing process parameters is demonstrated, as well as the ability to weave such fibers. This work establishes a novel platform for biodegradable microstructured fibers for applications in implants, sutures, wound dressing, or tissue scaffolds.
Biodegradable multimaterial fibers with unprecedented microstructures are fabricated with the scalable thermal drawing process. Via the in‐depth understanding of the release properties of thin biodegradable films in the fiber form, complex release profiles of multidose patterns are successfully achieved. Owing to their tunable mechanical properties, such fibers could be particularly attractive in applications such as sutures or wound dressings.
The thermal drawing of a uniform capillary‐like fiber that integrates an encapsulated microchannel and an embedded capacitor system within a polymeric cladding is demonstrated. Such a fiber construct ...has versatile functionalities applicable to microfluidic sensing including the detection of the presence and travel distance of a fluid, real‐time flowrate sensing, and high‐accuracy identification of the static dielectric constant, which reveals information on the nature of the fluid inside the channel. As a capacitive device, the fiber exhibits a broad operative frequency range from 100 Hz to 2 MHz, and is capable of sensing microflows with a wide flowrate range from 50 nL min−1 to 10 mL min−1. Beyond such performance, the novel fabrication approach proposed, based on fiber processing, is highly scalable and can potentially yield tens‐of‐kilometers of such fibers in a single draw, equating millions of short (few centimeters) working capillaries. It offers significant opportunities for reliable monitoring and manipulation of complex microfluidics, especially in cases requiring flexible and disposable sensors, at a scalability and cost traditionally associated with fiber processing technologies.
Uniform capillary‐like multimaterial fibers that integrate an encapsulated microchannel and an embedded capacitive sensor system are fabricated using the scalable thermal drawing technique. The fiber constructs show versatile functionalities for microfluidic sensing, including the detection of the presence and travel distance of a fluid, real‐time flowrate sensing, and high‐accuracy identification of the static dielectric constant of the fluid.
The integration of semiconducting materials within thermally drawn multi-material polymer fibers is emerging as a versatile platform for flexible optoelectronics and advanced fabrics. Developing a ...deeper control over the microstructure of the electrically addressed semiconducting domains has so far been marginally explored. Here we compare a simple annealing treatment of the as-drawn fiber, with a laser-based approach to tailor the microstructure post-drawing. We show that the laser treatment enables better control over the crystallization depth and leads to a microstructure with significantly larger grains. These results are also revealed through optoelectronic characterization, where the better microstructure leads to significantly improved photoresponsivity and photosensitivity, compared to that of regular heat treated fiber, paving the way towards high performance optoelectronic polymer fiber devices.
We demonstrate innovative simple and scalable fabrication approaches to realize highperformance polycrystalline semiconductor at the tips of a multi-material fiber. The photoresponsivity is two to ...three orders of magnitude higher than that of the as-drawn fiber. Such novel devices will enable flexible photodetecting probes.
In the version of this Article originally published, the volume, article number and year of ref. 32 were incorrect; they should have read 31, 1802348 (2019). This has now been corrected.
We will show how controlling the fluid dynamics of glasses and polymers can result in the scalable fabrication of optical metasurfaces and multimaterial fibers. Some applications in the IR region ...will also be discussed.
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