Scientists can now transform stress into electricity

The concept might sound unfamiliar to most, but millions of people have seen the effect in practice. It’s what happens when an analog record player’s needle reads a disk’s grooves. Through the piezoelectric effect, those vibrations of the needle are transformed into electrical impulses, which are then turned into sound waves. At its most basic level, the piezoelectric effect is how mechanical movements generate electricity and how it can be used elsewhere. 

While the substance doesn’t seem to be anything we’ve seen before with the effect, many other researchers praise it for pushing the limits of previous understanding of the piezoelectric effect. Traditional understanding was limited to hard structures like crystals. However, Dorina Opris and her team at Empa looked for something unique.

Shaping the future

Rubber is a composite material made of polar nanoparticles and an elastomer. The team used silicone in the prototype. The material was made in large part by Yee Song Ko, a Ph.D. student at Empa. He shaped the composite materials and the elastomer before connecting them. Song Ko needed to make an internal polarization using a strong electrical field. The team heated the film until the nanoparticles transitioned from a solid, glassy state into a rubbery and slightly viscous one. This allowed the researchers to manipulate the polarity and, thus electrical field. Then, researchers ‘solidified’ the orientation of the field by cooling the film to room temperature. 

One of the most exciting uses of this technology could be in the advancement of soft robotics and allowing robots to “feel” their surroundings. The material could send impulses to the device to be “understood” by a robotic system. 

Further, the material could make a significant impact in the medical field. “This material could probably even be used to obtain energy from the human body,” said Opris. “You could implant it near the heart to generate electricity from the heartbeat.” This could allow pacemakers to power themselves without requiring invasive procedures to change the batteries. 

The biggest downside to this material? As with most other novel materials, it can be challenging to reproduce and upscale at a reasonable cost. But of course, this could change with time.