Mechanoelectric energy conversion is a viable method for powering miniaturized hydrogel-based electric generators, including cardiac pacemakers, brain stimulators, wearable medication delivery systems, and so on.
A research team led by Professor Lizhi Xu from the Department of Mechanical Engineering at the Faculty of Engineering at the University of Hong Kong (HKU) has created a high-performance mechanoelectrical energy converter using hydrogels, a water-rich soft polymeric material.
To build the electric generator, the researchers sandwiched an ion-loaded hydrogel between two electrodes. The research paper, “A high-current hydrogel generator with engineered mechanistic asymmetry,” was published in Nature Communications.
Professor Xu said
With these asymmetric designs, the electrical output of the hydrogel generators was enhanced by orders of magnitudes, which is important for the powering of miniaturized biomedical devices.”
The positively and negatively charged ions in the hydrogel will travel at different speeds when the device is mechanically compressed. The external circuit can use the voltage and current produced by the separation of electric charges.
By utilizing the device’s asymmetric designs, the study team was able to significantly increase the electrical output, surpassing that of previous systems by achieving an exceptionally high level of 5.5 mA/m2 and 916 mC/m2 every cycle. In comparison to other flexible generators and triboelectric nanogenerators, for instance, it is roughly ten times greater.
Because hydrogels are pliable, soft, and can be made to resemble biological tissues, they make excellent body-conformal device constructions. Professor Xu stated, “They can adapt to the shape of different bodily tissues and are quite biocompatible.
The research demonstrated the use of a soft patch for regulated medication release. Numerous other biomedical equipment, like wearable health monitoring, VR/AR interfaces, cardiac pacemakers, etc., can also benefit from this technology.
