Entropy‐Assisted Flexible Nanofibrous Dielectrics Enable High‐performance Strain Sensing

Abstract Ceramics possess notable attributes including high‐temperature stability, strong chemical tolerance, and exceptional wear resistance, rendering them highly promising for various applications. Nevertheless, the brittleness of ceramics presents a substantial hurdle in harnessing their full potential for applications in wearable devices and unconfined loading environments. In this study, an entropy‐assisted strategy is proposed to realize the flexibility of Bi 4 Ti 3 O 12 ‐based dielectric nanofibers. The findings illustrate that augmented atomic configurational entropy within the nanofibers instigates favorable structural changes, including the development of refined grains and a substantial amorphous component, thereby leading to the notable improvement in the flexibility of ceramic nanofibers with functional properties. The flexible high‐entropy nanofibers enable the development of a high‐performance capacitive strain sensor with remarkable response sensitivity (1.62 kPa −1 ), wide temperature range adaptability over 25–350 °C, and excellent fatigue resistance over 3000 cycles. Importantly, this entropy‐driven approach holds promise for the advancement of flexible functional ceramics, extending beyond simple oxides such as amorphous silica and alumina.