A waterproof, environment‐friendly, multifunctional, and stretchable thermoelectric fabric for continuous self‐powered personal health signal collection at high humidity

Abstract

Thermoelectric sensors have attracted increasing attention in smart wearables due to the recognition of multiple signals in self‐powered mode. However, present thermoelectric devices show disadvantages of low durability, weak wearability, and complex preparation processes and are susceptible to moisture in the microenvironment of the human body, which hinders their further application in wearable electronics. Herein, we prepared a new thermoelectric fabric with thermoplastic polyurethane/carbon nanotubes (TPU/CNTs) by combining vacuum filtration and electrospraying techniques. Electrospraying TPU microsphere coating with good biocompatibility and environmental friendliness made the fabric worn directly and exhibits preferred water resistance, mechanical durability, and stability even after being bent 4000 times, stretched 1000 times, and washed 1000 times. Moreover, this fabric showed a Seebeck coefficient of 49 μV K−1 and strain range of 250% and could collect signals well and avoided interference from moisture. Based on the biocompatibility and safety of the fabric, it can be fabricated into devices and mounted on the human face and elbow for long‐term and continuous collection of data on the body's motion and breathing simultaneously to provide collaborative support information. This thermoelectric fabric‐based sensor will show great potential in advanced smart wearables for health monitoring, motion detection, and human–computer interaction.

Weavable thermoelectrics: advances, controversies, and future developments

“…These fibers include carbon-based materials (such as CNTs) [43,[122][123][124][125][126][127][128][129][130], organic conducting polymers (such as PEDOT:PSS) [131][132][133][134][135][136][137][138][139][140][141][142][143][144][145][146][147], and some inorganic materials (such as core-shell structured thermoelectric fibers) [148][149][150][151]. Composite fibers have also been extensively studied, including composites of carbon and organic materials [42,[152][153][154][155][156][157][158][159][160][161], carbon and nano-inorganic materials [162], and composites of organic materials as matrices with nanoinorganic materials as fillers [163][164][165]…”

“…Till now, there have been many types of carbon/organic hybrid fibers for applying to weavable thermoelectrics, including CNT/PEDOT:PSS yarns [153][154][155]160], CNT/PANI fibers [161], PEI-doped CNT yarns [156], WPU and PVA wrapped SWCNT yarns [158], thermoplastic polyurethane/CNT yarns [152], etc. Similar to pure carbonbased and conducting-polymer-based thermoelectric fibers discussed above, carbon/organic hybrid fibers can also be fabricated with p/n segments.…”

Strain-Temperature Dual Sensor Based on Deep Learning Strategy for Human–Computer Interaction Systems

“…Recently, due to advances in electronic technology, there has been a significant trend toward smaller, more flexible, and wearable electronic devices. These flexible wearables are highly sensitive, biocompatible, and comfortable and have applications in human medical monitoring, − soft robotics, , electronic skin, , and artificial intelligence. , Current sensor technologies primarily utilize capacitive, , piezoelectric, , resistive, and optical sensing methods. , However, developing a versatile electronic skin using a single sensing material remains a major challenge for widespread adoption …”