Researchers develop a composite film to produce hybrid piezo-triboelectric nanogenerators, paving the way for more sustainable and self-sufficient electronic devices.
There is a push towards developing ultra-low-power electronic devices that can be powered by ambient energy harvesting solutions such as piezoelectric and triboelectric effects to convert mechanical energy into electrical energy. Piezoelectric materials generate an electrical charge when stressed mechanically, whereas triboelectric effect is the induction of charges on two dissimilar materials after they have come in contact with each other.
Researchers and engineers have developed piezoelectric nanogenerators (PENG), triboelectric nanogenerators (TENG), and even hybrid piezo-triboelectric energy harvesters (HNG) that have improved energy harvesting capabilities. These devices require dielectric materials that retain their polarization, and multiferroic materials that exhibit ferromagnetic and ferromagnetic properties suitable in this case.
Now, the researchers from Daegu Gyeongbuk Institute of Science and Technology (DGIST), Korea and Indian Institute of Technology, Guwahati, India, develop a composite film that can be used in combination with other materials to produce energy harvesting generators. The film is developed using a cost-effective technique where a multiferroic material, bismuth titanate, is added to a flexible triboelectric polymer (PDMS).
These layers function as electrodes, and as the device is pressed and released, the piezoelectric and triboelectric nature of the film synergize with each other to generate charges on the electrodes, creating a voltage. Researchers observe that this effect enhances the energy harvesting performance.
Prof. Hoe Joon Kim from DGIST, who led the study, states, “For the first time, the single-phase room-temperature multiferroic material with colossal dielectric constant has been achieved. The internal polarization amplification of the polymer was improved, boosting the energy harvesting performance of the hybrid energy harvester.”
Researchers believe that their nanogenerators could one day invalidate batteries in many cases, making electronics more sustainable and self-sufficient.
The research appeared in the journal Nature Energy.