Compliant and breathable electrospun epidermal electrode towards artifact-free electrophysiological monitoring

Sustainable epidermal electronics offers unprecedented opportunities for reflecting the real-time body's health state and preventing environmental pollution, enabling an augmented level for portable electronic advances. However, the severe limitations of inadequate interfacial adaptability and breathability lead to difficulties in maintaining long-term on-skin signal recording. Herein, a self-adhesive, breathable, biodegradable, and on-skin compatible epidermal electrode is engineered via electrospinning method that consists of hydroxypropyl methylcellulose (HPMC) based porous textile configuration connected in series with surface printed Ag interdigital electrode, affording exceptional permeability (∼102 g·m−2·h−1), unparalleled conductivity (∼212 S·m−1), and user-friendliness. Benefiting from ultra-thin characteristics (∼18 μm) and abundant non-covalent bonding with arbitrary curvilinear skin surfaces, the skin-friendly electrode can naturally adapt to local surface topographies even under sweaty conditions without auxiliary adhesions, overcoming the bottleneck of interfacial deterioration under complex sensing scenarios. Successful demonstrations of portable and wireless readout system realize high resolution signal recording on multi-mobile user interfaces that are competitive with commercial Ag/AgCl electrodes for artifact-free electrophysiological signal monitoring. More encouragingly, the assembled electrode that is capable of degrading into environmentally benign constitutes would effectively alleviate electronic waste disposal issues. This work provides enormous potential to develop eco-friendly and conformal epidermal electrodes with minimized interference to skin homeostasis towards long-term physical health management.