Stacked MXene/PEDOT-PSS Electrode Fiber for High-Performance Recording and Stimulation

The development of microelectrodes with high electrical performance is imperative, particularly for invasive interfaces such as deep brain stimulation (DBS) electrodes. MXene, a new family of 2D early transition metal carbides or nitrides, exhibits outstanding electrical properties and has been researched to improve bioelectronic interface. Through a wet spinning process, we fabricate MXene/PEDOT-PSS electrode fibers measuring 30 m in diameter, exhibiting an electrical conductivity of 2.16 {+/-} 1.46 x 10^5 S/m and notably low interfacial impedance. The excellent cathodic charge storage capacity (CSCc) and charge injection capacity (CIC) lead to their high performance in recording or stimulation. The electrode fibers are electrochemically stable, biocompatible, magnetic resonance imaging (MRI)-compatible, and demonstrate excellent performance in electromyography (EMG), electrocardiograph (ECG), cortical recording and subthalamic nuclei deep brain stimulation (STN-DBS) experiments.