Paper-powered generator for portable devices

Many everyday electronic devices, such as remote controls and watches, require only tiny amounts of energy to operate, so the notion of powering them through rechargeable batteries that ultimately draw down from the electricity grid seems decidedly inelegant.

Now, however, researchers led by Hengyo Guo from the Beijing Institute of Nanoenergy and Nanosystems in China have developed a proof-of-concept portable structure that can power low-demand devices using the energy generated simply by quotidian body movements.

The charger, described in the journal ACS Nano, is inspired by the venerable Chinese and Japanese art of precision paper cutting. 

It takes the form of a wallet-sized paper-based lattice, coated with gold, graphite and fluorinated ethylene propylene film to create what the researchers call a “triboelectric nanogenerator” (or TENG). 

Pressing and releasing the TENG for just a couple of minutes – in the same way that would occur if it was, say, stashed in a coat pocket while the wearer was walking – accumulates a charge of one volt.

This, write the scientists, makes it “a sustainable power source for driving wearable and portable electronic devices such as a wireless remote control, electric watch, or temperature sensor”.

Guo’s team has been active in developing TENGs for several years, but the paper-based design represents a significant improvement in both construction and materials. Previous models have been made of acrylic, which makes them heavy, and required to several hours of motion and pressure to build up sufficient charge to operate a low-energy device.

The new version, dubbed, unromantically, “a cut-paper-based self-charging power unit”, has evident and obvious commercial application.

“The development of lightweight, super-portable, and sustainable power sources has become an urgent need for most modern personal electronics,” the researchers note.