February 24, 2017
Green tea has many health perks, from preventing heart disease to increasing one’s metabolism. But now green tea may have one more capability — powering wearable electronics.
Scientists developed a flexible, compact and rechargeable energy storage device for wearable electronics using polyphenols found in green tea, according to a new study published in The Journal of Physical Chemistry C.
“Our objective is to fabricate wearable electronic devices. Compressible energy storage devices are the first step towards achieving that objective,” said Kothandam Krishnamoorthy, from the CSIR-Network of Institutes for Solar Energy.
Finding a reliable, long-lasting energy source for wearable electronics remains to be a big hurdle. Supercapacitors, which are devices that regulate and store energy, are inconvenient, and the compressed ones do not work as well. These devices are typically made with carbon-coated polymer sponges, which often bunch up and impair performance.
However, this new green tea-infused breakthrough may finally be able to overcome this roadblock.
“If you brew green tea and leave it for a while in a glass, you will see a coating. The coating comprises polyphenols, which are the antioxidants in green tea. They are capable of reducing metal ions such as silver,” said Krishnamoorthy. “We could use polyphenols in green tea to prepare metal coated sponges that are essential for the fabrication of compressible supercapacitors.”
Scientists produced polymer gels in green tea extract, infusing polyphenols from the tea into the gels. Polyphenols are natural compounds found in food that have powerful antioxidant properties. Through this process, the supercapacitor was eventually able to generate enough energy to power a heart rate monitor, LEDs or a Bluetooth module. Even after being compressed more than 100 times, the device was still able to perform well.