Wearable electronics can be permanently powered by elastic, self-healing materials, which use body heat to generate electricity. Three carefully selected organic compounds have been combined to create a prototype of a thermoelectric material, which would be resilient and self-healing, could generate their own electricity, and was strong enough, to withstand stress and stress of everyday life.
Sensors, which is worn on the skin or in the form of implants, are becoming an increasingly popular way of collecting biological data for personal and medical reasons. They can keep track of valuable health indicators, such as heart rate, arterial pressure, brain activity, muscle movements, calories burned and the release of certain chemicals. Final goal – portable self-powered technology, but they require a reliable and durable power source.
Thermoelectric materials using thermal gradients to generate electricity. They have the potential to power wearable technology, using body heat, eliminating the need for batteries, but modern materials do not have enough flexibility, strength and elasticity, to avoid permanent damage.
A team led by Deriey Baran and Seuong Ki of KAUST has recently published a study in Advanced Functional Materials, wherein they mixed thermoelectric highly conductive polymer PETOT: PSS (foot (3,4-ethylenedioxythiophene), doped with polystyrene sulfonate), with dimetilsulyfoksidom. organic compound, increases the efficiency of PETOT: PSS и Triton X-100, adhesive gel-like substance, promoting hydrogen bonding with PETOT: PSS.
"This last ingredient needed to ensure we need flexible and self-healing properties", – says Kee.
The researchers used 3D-printing machine for the mixtures thereof in thick layers, and then check the thermoelectric properties of these films under pressure. First of all, they found, that the temperature difference 32 degrees Celsius between the two sides of the film generates a maximum output power 12,2 NW.
The team then checked the self-healing properties of the films, by cutting them in half with a razor blade, while they are nourished LED light.
"It's amazing, but the light did not go out during or after the cutting ", – says Kee. "I repeated ten times cut, but he continued samovosstanovlyatsya less than one second and kept 85% its output ".
Besides, when they stretched film by about a third longer than its original size, it still provides a stable power supply.
"Wearable electronics is in constant tension, and their power sources likely to fail ", – says Kee. "Our material can provide continuous and reliable power, because it can deform, stretch and, the most important thing, heal itself ".
Twelve NW enough to power many devices, with the exception of, possibly, high performance biosensors and transmitters, but it is a promising start.