Nanowires in Flexible Sensors: Structure is Becoming a Key in Controlling the Sensing Performance

Abstract

Flexible sensors, as a kind of indispensable branch of flexible electronics, are garnering substantial in medical and industrial applications. Ever‐evolving advances in nanowires in their myriad forms have fueled many of the developments in this field. However, recent researches have extensively focused on the intrinsic properties of these nanomaterials, rationally designed structures, which are pivotal in sensing performance, to a large extent, are undervalued. Hereon, the latest advances in the structure design, together with controlled fabrication of nanowires for better sensing performance are highlighted. In specific, nanowires are classified according to morphologies and hybrid forms and their corresponding fabrication methodologies and influence on sensing properties are briefly discussed. Then, construction strategies for nanowire‐based sensors, including materials assembly and macroscopical design are systematically summarized. Subsequently, the characteristics and advantages of flexible sensors induced by various nanowires, including physical/physiological/multifunctional parameters sensing are reflected in the application examples. Finally, conclusions and challenges are presented for the development of nanowire‐based flexible sensors, as well as frontier strategies especially bionic design. This review is aimed at providing a valuable and systematic understanding of nanowires in sensing system and then serves as inspiration for intelligent designs in flexible future electronics.

A comprehensive review on the biomedical frontiers of nanowire applications

“…The development of functionalized nanowires for medication administration and bioenergy generation is then discussed. The limits of nanowires today are finally discussed, along with a prediction for the next wave of nanowire-based bio-interface devices [ 525 ]. We methodically enumerate the working theory, material platform, fabrication technique, and transformative applications made possible by cutting-edge quantum dots in superconducting nanowire single-photon detectors and nanowire emitters in this paper [ 526 ].…”

Biomimetic Wearable Sensors: Emerging Combination of Intelligence and Electronics

“…Biomimetic structures derived from nature offer rich learning resources for the development of wearable sensing materials. For example, the crack structure is derived from the foot seams of scorpions, [ 75 ] the hierarchical interlocked structure of human skin [ 76 ] is sensitive to strain, the whiskers of spiders [ 77 ] and cats [ 78 ] can sensitively feel the external air flow and vibration, and the hierarchical structures of lotus leaves can provide superhydrophobic interfaces and self‐cleaning abilities. [ 15a ] Nacre's “brick and mortar” structures offer high toughnesses, [ 21 ] while gecko pads, [ 16b ] octopus suckers, [ 18a ] and tree‐frog pads [ 17 ] provide dense adhesive structures.…”

Recent Advances in Nanowire-Based Wearable Physical Sensors

“…Nanomaterials, characterized by their high specific surface area, mechanical properties, and electrical properties, have emerged as promising sensitive materials for wearable sensors [29][30][31]. Graphene [32,33], carbon nanotubes (CNTs) [34,35], nanowires (NWs) [5,[36][37][38], nanoparticles [39,40], quantum dots (QDs) [41,42], nano-patterned thin films [43,44], nanostructured materials [45,46], nanocomposite materials [47,48], and more have been employed in this domain. Among them, NWs are one-dimensional nanostructures with diameters ranging from a few nanometers to hundreds of nanometers and lengths up to several micrometers or even millimeters.…”

“…The transparency is related to the thickness of the film, which makes spray-coating a good choice for preparing transparent NW networks for wearable sensors [50]. Moreover, NWs can be synthesized by various methods with different materials, such as metals, semiconductors, and oxides, which provide a rich diversity of NW-based wearable physical sensors for different applications [5,[29][30][31]36].…”