Thermoelectric energy harvesting electronic skin (e-skin) Patch with reconfigurable carbon nanotube clays

Advances in the electronic skin (e-skin) have led to the next electronic paradigm, which involves the integration of devices with the human body. However, skin-adaptable permanent power technology is immature in terms of improving sensitivity to explosion hazard and facilitating wire/wireless charging, thus restricting the practical application of the e-skin. Here, we present a thermoelectric clay made of carbon nanotubes (CNTs) and non-ionic surfactants as viscous additives for use in skin-adaptable permanent power sources for the e-skin. The controlled kneading ratio of the CNT to the viscous additive (1:5) makes the thermoelectric clay reconfigurable with a lower elastic modulus than that of the human skin, providing skin adaptability with high elongation up to 100% and remendability after chapping. Through chemical doping, we produced n-type and p-type thermoelectric clays, optimized their electrical conductivities and Seebeck coefficients, and obtained enhanced ZT values. The thermoelectric output power was preserved over 80% of the initial value even more than one year. Finally, a skin adaptable thermoelectric power patch for the e-skin was fabricated with five pairs of n-type and p-type thermoelectric clays, and its performance was demonstrated. The patch was successfully operated under severe folding, twisting, stretching on the human skin and even when punctured state at room temperature.

Automated summary

This study introduces a skin-adaptable permanent power technology for electronic skin, which achieves high elongation and remendability through thermoelectric clay, greatly improving thermoelectric performance. Test on human skin suggests the technology can still operate successfully under severe conditions.