Flexible graphene/GO electrode for gel-free EEG

Area of Science:

• Biomedical Engineering
• Neuroscience
• Materials Science

Background:

• Advancements in electroencephalography (EEG) enable brain-computer interface (BCI) use outside labs.
• High-quality, biocompatible dry electrodes are crucial for long-term EEG monitoring in BCI.
• Previous Ag-flake electrodes were effective but costly for commercial use.

Purpose of the Study:

• Develop a cost-effective dry electrode for BCI applications using graphene/GO.
• Investigate the impact of varying graphene/GO content on electrode performance.
• Evaluate the dry electrode's suitability for real-world EEG recording and BCI tasks.

Main Methods:

• Fabricated dry electrodes using silicone gel, metal flakes, and graphene/GO.
• Produced two electrode types with differing graphene/GO concentrations.
• Assessed electrode impedance, signal correlation with wet electrodes, and EEG recording quality.
• Tested steady-state visually evoked potential (SSVEP) detection capabilities.

Main Results:

• Graphene/GO electrodes exhibited low impedance and strong signal correlation with wet electrodes.
• Good signal quality was achieved in eyes-open EEG recordings.
• Higher graphene/GO content led to surface irregularities and reduced signal quality.
• Dry electrodes reliably detected SSVEP, even in hairy scalp areas.

Conclusions:

• The developed graphene/GO dry electrode is a cost-effective alternative for BCI.
• The electrode demonstrates sufficient signal quality and reliability for BCI applications.
• Optimizing graphene/GO concentration is key to maximizing electrode performance.