Gold Tabs Pave the Way for Self-Powered Electronics

A new biotech device made with gold can generate electricity when attached to moving body parts. This technology could eventually be used to fuel wearable devices and even eliminate the need to carry device chargers.

The nanogenerator tab uses triboelectric charges to generate electricity. These charges are produced when certain materials come in contact with other materials. Static electricity is one example of a triboelectric charge.

This triboelectric nanogenerator is fabricated with two thin pieces of gold and a layer of polydimethylsiloxane (PDMS) inbetween. PDMS is a silicon-based polymercommonly used in contact lenses.

A prototype of the gold-tab triboelectric generator. (Image courtesy of Nano Energy)

To create the triboelectric charge, one layer of gold must first be stretched and then crumpled when it is released. The crumpled gold layer will lead to friction when the force is reapplied. For example, if this nanogenerator is attached to the skin of a finger,when the finger bends, itwill cause friction between the gold layers and the PDMS. More friction from this movement will result in morepower being generated as the electrons move between the gold layers. This electricity can then be transferred from a gold tab to an attached electronic device.

The human body is full of energy, so harnessing this energy to power devices is moreconvenient and portable than relying solely on chargers and traditional electric power sources. Plenty of research has already gone intostudying triboelectric nanogenerators, but these nanogenerators tend to be difficult and costly to manufacture.

Now, however, a team of researchers from University at Buffalo (UB) and the Institute of Semiconductors (IoP) at the Chinese Academy of Science (CAS) have been addressing these concerns in the development of their gold nanogenerator tab. This small, easy-to-manufacture tab, which is 1.5 centimeters long by 1 centimeter wide, can generate a maximum of 124 volts, 10 microamps, and 0.22 milliwatts per square centimeter.

Although this energy is not nearly enough to charge a mobile device, such as a smartphone, it can power 48 red LED lights at the same time. And the easy fabrication of this tab makes studying larger models using this same technique easier and more cost-effective. Models with larger pieces of gold could generate more energy—perhaps even enough to quickly charge a mobile phone.

Lead author Qiaoqiang Gan, PhD (left), and coauthor Nan Zhang (right) are among the researchers behind the triboelectric nanogenerator research project. (Image courtesy of Douglas Levere/University at Buffalo.)

The team of researchers from UB’s School of Engineering and Applied Sciences include lead author Qiaoqiang Gan, PhD, an associate professor of electrical engineering, and Nan Zhang, a PhD student. In addition, the collaborative researchers from IoP at CAS are professor and lead author Yun Xu, PhD, and coauthor Huamin Chen.

At UB, Zhang is now working with a team of undergraduates to increase the tab’s energy performance. There are also researchers developing a portable battery that stores energy generated from the tab, which could potentially be used as an energy source for wearable and self-powered devices.

A recent press release from UB describes the triboelectric nanogenerator tab study, and the team’s research has been published in the April 2018 issue of Nano Energy.

Learn more about power generated from wearable technology with Microbial Fuel Cells May Be the Future of Batteries for Wearables.