The new energy-generating device was made by combining piezoelectric composites with carbon fibre-reinforced polymer (CFRP), a commonly used material that is both light and strong.
This composition allows it to transform vibrations from the surrounding environment into electricity.
"Everyday items, from fridges to street lamps, are connected to the internet as part of the Internet of Things (IoT), and many of them are equipped with sensors that collect data," said Fumio Narita, co-author of the study and professor at Tohoku University. "But these IoT devices need power to function, which is challenging if they are in remote places or if there are lots of them."
In order to leverage the vibrational energy, the team relied on piezoelectric materials' ability to generate electricity when physically stressed. This was then combined with the durability and lightness of a material like CFRP.
"We pondered whether a piezoelectric vibration energy harvester (PVEH), harnessing the robustness of CFRP together with a piezoelectric composite, could be a more efficient and durable means of harvesting energy," said Narita.
The principle, structural design, and application of carbon fiber-reinforced polymer-enhanced piezoelectric nanocomposite materials. / Tohoku University
Image credit: Tohoku University
The group fabricated the device using a combination of CFRP and potassium sodium niobate (KNN) nanoparticles mixed with epoxy resin. The CFRP served as both an electrode and a reinforcement substrate.
The results of the testing showed that the new device could maintain high performance even after being bent more than 100,000 times. It also proved capable of storing the generated electricity and powering LED lights, while outperforming other KNN-based polymer composites in terms of energy output density.
As a result, the team suggested the new device could help propel the development of self-powered IoT sensors, leading to more energy-efficient IoT devices.
"As well as the societal benefits of our C-PVEH device, we are thrilled with the contributions we have made to the field of energy harvesting and sensor technology," Narita said. "The blend of excellent energy output density and high resilience can guide future research into other composite materials for diverse applications."
Details of the group's research were published in the journal Nano Energy.
