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Vol. 18 (2026)

Bioinspired Dual-Scale Crack Manipulation Enabling 325%-Stretchable Metal Film Conductors for AI-Empowered Electronic Skins

https://doi.org/10.1007/s40820-026-02152-5
Tianming Sun
State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People’s Republic of China
Bin Feng
Nanotechnology Center, School of Fashion and Textiles, The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, People’s Republic of China
Guisheng Zou
State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People’s Republic of China
Jinpeng Huo
State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People’s Republic of China
Bo Bi
State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People’s Republic of China
Jin Peng
State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People’s Republic of China
Zehua Li
State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People’s Republic of China
Gongbo Bian
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, People’s Republic of China
Bingang Xu
Nanotechnology Center, School of Fashion and Textiles, The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, People’s Republic of China
Lei Liu
State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People’s Republic of China

Corresponding Author: Lei Liu

liulei@tsinghua.edu.cn

Nano-Micro Letters, Vol. 18 (2026), Article Number: 318

Abstract

The advancement of electronic skins toward commercialization calls for cost-effective and robust flexible conductors, among which metal films are attractive candidates but suffer from poor stretchability. Conventionally, cracks formed in strained metal films are universally considered detrimental and sought to be suppressed. Herein, we demonstrate that cracking is not a drawback, but rather an effective design parameter for on-demand tailoring of film properties. By exploiting the size effect in crack engineering, we propose a bioinspired, dual-scale architecture that endows metal film conductors with up to 325% stretchability. We show that through the synergy of nanoscale pore implantation and microscale substrate roughening, progressively evolved crack patterns can be programmed within metal films by modulating structural parameters. This tunable film cracking behavior yields a nearly 25-fold regulation of stretchability, representing a remarkably wide tunable range among previously deposited metal counterparts. Leveraging these advances, a stretchable metal film-based, AI-empowered electronic skin is constructed, demonstrating excellent practicality across diverse flexible sensing scenarios. Our strategy highlights the pivotal role of the size effect in precise crack manipulation, and the multi-scale regulation paradigm establishes a fresh route to performance improvement of flexible conductors.


Highlights:
1 A leaf-inspired hierarchical architecture is developed to enable micro-nano, dual-scale crack manipulation in metal films, leading to a nearly 25-fold regulation of stretchability (from 12% to 325%).
2 A stretchable metal film-based, AI-empowered electronic skin is developed, demonstrating excellent applicability in human motion monitoring, sign language translation, and speech recognition.
3 The role of metal film cracking in stretchable electronics is reinterpreted, shifting from an unfavorable failure phenomenon into a powerful design tool for on-demand tuning of electromechanical properties.

Keywords

Hierarchical Artificial intelligence Flexible sensors Stretchable electronics Stretchable conductors Flexible conductors
Sun, Tianming, Bin Feng, Guisheng Zou, Jinpeng Huo, Bo Bi, Jin Peng, Zehua Li, Gongbo Bian, Bingang Xu, and Lei Liu. 2026. “Bioinspired Dual-Scale Crack Manipulation Enabling 325%-Stretchable Metal Film Conductors for AI-Empowered Electronic Skins”. Nano-Micro Letters 18 (April):318. https://doi.org/10.1007/s40820-026-02152-5.
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