Powering the Future

Pioneering research into piezoelectricity has the potential to change the way we generate electricity in the future – in a sustainable, eco-friendly way.

The way in which we generate electricity has won many headlines over the past number of years.

The earth’s disappearing supplies of coal and oil have necessitated the development of more sustainable sources, but many of these have brought their own controversy along with their benefits. Wind turbines are becoming an increasingly common sight throughout Ireland, but the location of wind farms needs to be carefully considered in terms of their impact on communities and neighbouring houses. And while wind energy is considered a viable form of energy production for the future, there are ongoing efforts to find even easier and even more sustainable forms of electricity generation to give us more options, both now, and in the years to come.

One of the most promising research areas is in piezoelectricity, and thanks to pioneering research by University of Limerick (UL), this looks to be one of the most exciting potential areas for electricity generation in the future. Sarah Guerin, a Science Foundation Ireland-funded post-graduate researcher at the Department of Physics and the Bernal Institute at UL, explains exactly what piezoelectricity is. “Piezoelectricity translates as ‘pressing’ electricity. It is a property of certain materials, whereby squeezing or bending them makes them generate electricity. They will also strain themselves if electricity is passed through them.”

Piezoelectricity is commonly used in consumer devices such as cars, phones and games consoles.

Piezoelectricity is commonly used in consumer devices such as cars, phones and games consoles. Traditionally, the materials used are synthetic and often contain toxic elements such as lead or lithium – and so the challenge was to find a more sustainable and safe form of producing piezoelectricity. “Currently, the majority of consumer electronics use inorganic materials for sensing, which contain zinc, lead and aluminium,” explains Sarah.
“The materials we study are proteins and amino acids, which occur naturally and can be used for unique applications.”

Sarah and a group of scientists at UL’s Bernal Institute have discovered that the biomolecule glycine, when tapped or squeezed, can generate enough electricity to power electrical devices in a sustainable and economically viable way. The team begins by identifying suitable materials using computer models. “What attracted me was the computational aspect of my own research,” Sarah reveals. “I use computer simulations to predict which biological materials have the most desirable properties. This speeds up experiments as we can focus on the most promising materials. We also study biological piezoelectricity in its crystallised form, and growing crystals and measuring their properties is a challenging and fun area of scientific research.”

Aimee Stapleton, an Irish Research Council EMBARK Postgraduate Fellow in the Department of Physics and Bernal Institute of UL, is also researching piezoelectricity, and is the co-author of a paper that details how applying pressure to a protein found in egg whites and tears, lysozyme, can generate electricity. “We know a lot about how piezoelectricity works in conventional materials but much less about how it works for biological materials. As a physicist, I was curious if the same rules of physics were at play. It’s fascinating that at the crux of piezoelectricity in both solid state samples and protein samples is their crystal structure. This knowledge will underpin future applications of our research.”

The potential for this research in consumer terms
is pretty astounding when you consider how widely piezoelectricity is used. “Piezoelectric materials are absolutely everywhere – vibration sensors and touch screens in phones, video game controllers, car sensors, scientific equipment, microphones, speakers, lighters, printers, and even musical greeting cards,” says Sarah.

Biological piezoelectric materials can be used for wearable and implantable electronics, that can sense things like blood flow inside the human body

With such a huge range of products and applications depending on piezoelectric materials, finding economically sound and environmentally sustainable biomaterials is a vital forward step, not just for Ireland, but the world. “These organic materials are the future for piezoelectricity,” she continues. “Biological piezoelectric materials can be used for wearable and implantable electronics, that can sense things like blood flow inside the human body. This could help to monitor and treat disease and help in the revolution of personalised medicine. I also like thinking about the energy harvesting potential of these materials – applications like charging your phone by walking or running.”

It’s an exciting area for researchers, but also for consumers who can rest safe in the knowledge that their favourite devices won’t be going anywhere anytime soon thanks to the pioneering research performed by scientists in Ireland and further afield.

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