All-inorganic flexible high-temperature strain sensor based on SrRuO3/muscovite heteroepitaxy

Design and fabrication of flexible strain sensors are still challenging for high-temperature application in the aerospace, metallurgical industry, and underground energy exploration. In the present work, an all-inorganic flexible strain sensor has been fabricated based on single-crystal SrRuO3 (SRO) thin films epitaxially grown on muscovite. A high resistive tunability (( increment R/R-0%) similar to 26.05%), excellent linearity (correlation coefficient of 0.93), and large gauge factor (GF similar to 101) have been achieved in the as-prepared SRO-based sensors with great bending durability. The mechanism for the tunability of the electrical transport in flexible SRO thin films under mechanical bending is proposed based on the Raman and X-ray photoelectron spectroscopy results. The sensors have been confirmed to work properly from ambient temperatures up to similar to 425 K, showing the potential application in high-temperature environments. Moreover, the flexible sensors have the ability to monitor the hand joint movements.