A high-current hydrogel generator with engineered mechanoionic asymmetry.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38374305.
- Also identified by DOI 10.1038/s41467-024-45931-7 and PMC identifier 10876576.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Mechanoelectrical energy conversion is a potential solution for the power supply of miniaturized wearable and implantable systems; yet it remains challenging due to limited current output when exploiting low-frequency motions with soft devices. We report a design of a hydrogel generator with mechanoionic current generation amplified by orders of magnitudes with engineered structural and chemical asymmetry. Under compressive loading, relief structures in the hydrogel intensify net ion fluxes induced by deformation gradient, which synergize with asymmetric ion adsorption characteristics of the electrodes and distinct diffusivity of cations and anions in the hydrogel matrix. This engineered mechanoionic process can yield 4 mA (5.5 A m<sup>-2</sup>) of peak current under cyclic compression of 80 kPa applied at 0.1 Hz, with the transferred charge reaching up to 916 mC m<sup>-2</sup> per cycle. The high current output of this miniaturized hydrogel generator is beneficial for the powering of wearable devices, as exemplified by a controlled drug-releasing system for wound healing. The demonstrated mechanisms for amplifying mechanoionic effect will enable further designs for a variety of self-powered biomedical systems.