Bioactive Ion-Confined Ultracapacitive Memristors with Neuromorphic Functions

Area of Science:

• Bioinspired iontronics
• Materials science
• Nanotechnology

Background:

• Bioinspired iontronics offer promising biological applications by merging electronic devices with ionic systems.
• Porous carbon electrodes in ultracapacitive devices are key for controlling bioactive ions through electric double layers.
• Understanding bioactive ion interactions with porous carbons is crucial but challenging due to diverse ion structures.

Purpose of the Study:

• To investigate the adsorption mechanisms of ammonium-based cations with varying alkyl chain lengths within nanoporous carbons.
• To elucidate the relationship between ion adsorption and the resulting memristive behavior in all-carbon capacitive ionic memristor devices.

Main Methods:

• Utilized nanoporous carbons as electrodes.
• Investigated the adsorption of a series of ammonium-based cations with differing alkyl chain lengths.
• Analyzed ion behavior, including enrichment and depletion, during electric polarization.
• Characterized the memristive properties of the resulting all-carbon capacitive ionic memristor devices.

Main Results:

• Demonstrated strong physisorption of bioactive cations driven by synergistic hydrophobic and electrostatic interactions with negatively charged porous carbons.
• Observed irreversible adsorption and confinement of cations within nanoporous carbons, leading to anion enrichment and depletion under electric polarization.
• Confirmed characteristic memristive behavior in all-carbon capacitive ionic memristor devices due to these ion adsorption dynamics.

Conclusions:

• Established a clear link between ion adsorption mechanisms and the resistance state of memristors in all-carbon capacitive devices.
• Highlighted the potential of these findings for applications in drug delivery, biointerfacing, and neuromorphic computing.
• Advanced the understanding of ion-electrode interactions in bioinspired electronic systems.