Affiliation:
1. Wuhan University of Technology Hospital, Wuhan University of Technology Wuhan China
2. College of Civil Aviation Shenyang Aerospace University Shenyang China
3. Health Service Department General Hospital of Northern Theater Command Shenyang China
4. National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China
Abstract
AbstractBio‐compatible strain sensors are indispensable for human monitoring devices, requiring a delicate balance of robustness, flexibility, and sensitivity. However, achieving these attributes concurrently remains a formidable challenge. This article presents a pioneering approach to fabricate three‐dimensional flexible strain sensors using laser‐induced graphene (LIG) on polyimide (PI) substrates. Through a one‐step laser direct writing (LDW) technique, durable LIG/CuSO4 composites with closed‐pore porous structures are synthesized. The integration of copper sulfate within the closed‐cell architecture of LIG establishes a resilient conducting pathway, enhancing sensitivity to deformation under tensile stress. The resulting sensor exhibits exceptional performance in monitoring a wide range of human movements, from vigorous activities to subtle oscillations and physiological signals. Notably, the sensor boasts a remarkable sensing range of up to 25% strain, coupled with a high sensitivity characterized by a gauge factor of approximately 597. Rapid response times of 175 ms and quick recovery times of 200 ms further underscore its efficiency. Moreover, the sensor demonstrates outstanding stability and durability, maintaining consistent performance over 5600 cyclic experiments. This innovative approach represents a significant advancement in bio‐compatible strain sensor technology, offering a versatile solution for diverse monitoring applications.