Skin-Inspired Controllable Microcrack Electronic Skin with High Signal-to-Noise Ratio for High-Fidelity Pulse Wave Monitoring

Abstract

Wearable electronic skin (E-skin) with high sensitivity and stable response characteristics holds significant promise for human body monitoring. To address the critical bottleneck of stochastic microcrack morphology and poor structural controllability inherent in conventional MXene-based microcrack sensors, we present a skin-inspired, hierarchically structured E-skin in which ordered regulation of MXene microcracks is achieved through a pre-stretching–spray-coating coupling strategy. Benefiting from the synergistic interplay between structural engineering and conductive pathway modulation, the device achieves a sensitivity of 6.17 kPa^–1 over a pressure range of 0–60 kPa, along with a cycling stability exceeding 12000 loading–unloading cycles, a rapid response time of 40 ms, and a high signal-to-noise ratio (SNR) of 30.64 dB. By combining discrete wavelet transform (DWT) and continuous wavelet transform (CWT) for multi-scale analysis of radial and carotid arterial pulse signals, a dominant frequency of approximately 1.3 Hz (78 bpm) was extracted, validating the device’s high-resolution capability for detecting subtle physiological signals. This MXene-based microcrack E-skin offers a novel technical approach for the controllable fabrication of microcracks and demonstrates considerable potential for applications in wearable medical monitoring.

Graphical Abstract

Keywords

MXene / Tunable microcracks / Electronic skin / Flexible pressure sensor / Pulse wave monitoring

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Funding

Fujian Provincial Department of Industry and Information Technology(03)

Quanzhou Peak Shoes Co., Ltd. (CN)(2021KH20)

Science and Technology Department of Quanzhou(2022GZ4)

Technology Planning Project of Shaoxing(2024A13003)

Rights & permissions

Donghua University, Shanghai, China

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