Although sensitivity and durability are desirable in a sensor, both of them cannot be easily achieved. Site-specific and effective signal acquisition on the limited area of a sensor inevitably allows fatigue accumulation and contamination. For example, an ultrasensitive nanoscale-crack-based sensor for detecting a mechanical stimulus with tremendous sensitivity (a gauge factor greater than 2000 under 2% strain), yet limited durability (up to a few thousand stretching cycles in tensile tests) has been presented previously. Herein, we suggest a simple yet robust nanoscale-crack-based sensor that achieves remarkable durability through the use of a self-healable polymer. The self-healable polymer helps the crack gap recover and maintain high stability for 1 million cycles under 2% strain. Moreover, site-specific recovery with infrared light irradiation was demonstrated with monolithic arrayed sensors. The proposed strategy provides a unique solution to achieving highly enhanced durability and high mechanosensitivity, which are typically incompatible.
This study was supported by the Basic Science Research Program (NRF-2017R1D1A1B03033089 and 2016R1C1B1009689 (D. Kang)) through the National Research Foundation of Korea funded by the Ministry of Science, ICT and Future Planning. This study was also supported by the Basic Science Research Program through a National Research Foundation of Korea grant funded by the Korean Government (MEST; NRF-2017R1A5A1070259). D. Kang acknowledges financial support by the Ajou University research fund and the Nature-Inspired Innovative Technology Development Program through the National Research Foundation of Korea (NRF), which is funded by the Ministry of Science and ICT (NRF-2017M3C1B7014222).
