Developing new solutions to power human capability augmentation

From spy gadgets to the bionic eye, we are using engineering and technology to augment human capability. While these technologies and concepts mature, how to power them – ideally in an unobtrusive way – needs new solutions.

The dream way to help power everything is to take everyday motion, motion like rain drops falling, a person running or a heart beating, and convert it to electricity. These processes are called mechanical-to-electrical energy harvesters and can be easily produced from particular polymers. These energy harvesters have been held back from wide-scale use by the tremendous amounts of energy needed to produce them, more than they can harvest during their lifetime.

What we show

Whenever you touch your hand on a Van der Graaff generator, your hair straightens out and stands on end. The same thing happens with polymer chains when we pass electricity through them.

Girl touching Van der Graaf generator with hair spiked up due to electrical charge
Biswarup Ganguly, CC BY 3.0, via Wikimedia Commons

The problem here is we need a huge about of electricity to make the chains straight. Chemical Engineers from the University of Melbourne have found a way to make the polymer chains straighten or ‘crystallize’ without needing electricity. Using nanoscopic rigid sheets called ‘MXenes’ they have shown that polymer molecules can be aligned using chemistry rather than giant electric fields. Similar to how a metal sticks to a magnet, the polymer chains will straighten to stick to our MXene sheets. Since these MXenes are left mixed in with the polymers, the molecules don’t move over time, so the polymers stay straight forever.

The unique rigid sheet structure of the MXenes also means they can be processed easily, aligning as they're pushed out of a 3D printer nozzle, or settling parallel to each other during traditional film casting techniques.

This combination of straight polymers and ordered mXenes lets the researchers design polymer energy harvesters that outperform leading commercial devices (by a factor of 1.5) while being produced at a fraction of the cost (around $0.04 per square centimeter, compared to $0.28 for commercial films).

Applications

The roadblock to device integration – the huge energy cost – has been removed.

These cheap, highly efficient, polymer energy harvesters will soon find a home providing power to smart sensors in your clothing, the pacemaker in a heart, the augmented reality of google glasses, and at the joints of robotic suits – the list goes on.

This research was supported by the Australian Government through the Australian Research Council’s Linkage Projects funding scheme (LP160100071), Future Fellowships funding scheme (FT130100380), and Industry Transformation Research Hub funding scheme (IH140100018).

Read the full journal article in Nature here

Related topics

Technology and society Chemical engineering