Research progress on MXene-based electrophysiological electrodes

Electrophysiological signals, such as electromyogram (EMG), electrocardiogram (ECG), and electroencephalogram (EEG), provide critical insights into the state of human muscles, organs, and neural activities. These signals hold substantial value in applications such as disease diagnosis, health monitoring, and brain-computer interfaces. However, their high-fidelity acquisition is constrained by factors including the interface between the electrode and the skin (or tissue), the intrinsic properties of the electrode, and its biocompatibility. In recent years, transition MXene have emerged as ideal materials for fabricating electrophysiological electrodes due to their distinctive structure and properties. MXene exhibits outstanding electrical conductivity (~10000 S cm⁻¹), tunable surface functional groups (—O, —F, —OH, etc.), mechanical flexibility, and biocompatibility, enabling conformal contact with biological tissues and reducing interface impedance. This review first highlights the unique advantages and potential of MXene in physiological signal acquisition based on its structural and performance characteristics. Subsequently, the research progress of MXene in the field of electrophysiological sensing is discussed from both epidermal and implantable perspectives. Finally, the limitations of MXene-based electrodes in in vitro and in vivo electrophysiological sensing are summarized, and future research directions are proposed.