hemists in the Arts & Sciences at Washington University in St. Louis (WUSTL) (St. Louis, Missouri, USA) have developed a process for creating “smart bricks” that, much like a battery, store energy for future use. The chemists behind the smart brick method published a proof-of-concept in the August 11 edition ofNature Communications
“Our method works with regular brick or recycled bricks, and we can make our own bricks as well,” says Julio D’Arcy, assistant professor of chemistry at WUSTL. “As a matter of fact, the work that we have published in Nature Communications stems from bricks that we bought at Home Depot right here in Brentwood (Missouri); each brick was 65 cents.”
Red brick is generally regarded as among the cheapest and most common building materials I the world, having been used in walls and buildings for thousands of years. But the energy storing capabilities of red bricks has rarely been exploited for other uses.
Recognizing how red bricks absorb and store heat from the sun, D’Arcy and his colleagues investigated ways to convert these bricks into a type of energy storage device known as a supercapacitor. As D’Arcy explains, “In this work, we have developed a coating of the conducting polymer PEDOT, which is comprised of nanofibers that penetrate the inner porous network of a brick; a polymer coating remains trapped in a brick and serves as an ion sponge that stores and conducts electricity.”
The red pigment in bricks—known as iron oxide or rust—is key to triggering a polymerization reaction that releases stored energy. “PEDOT-coated bricks are ideal building blocks that can provide power to emergency lighting,” D’Arcy says. “We envision that this could be a reality when you connect our bricks with solar cells — this could take 50 bricks in close proximity to the load. These 50 bricks would enable powering emergency lighting for five hours.
“Advantageously, a brick wall serving as a supercapacitor can be recharged hundreds of thousands of times within an hour,” he adds. “If you connect a couple of bricks, microelectronics sensors would be easily powered.”
In addition, D’Arcy and collaborators at WUSTL’S Institute of Materials Science & Engineering are developing new methods of engineering cutting-edge microsupercapacitors from rust. The results of this study were published in the August 7 edition of Advanced Functional Materials.