Highly sensitive and low detection limit bionic flexible sensor inspired by the eggshell

Abstract The high‐performance flexible pressure sensors demonstrate significant potential in wearable electronics, robotics, human‐machine interfaces, and healthcare. However, the preparation of bionic flexible sensors with high sensitivity and low detection limit is still a big challenge. This study proposes a bionic flexible sensor based on the hierarchical microstructure of eggshells, which improves sensing performance and reduces detection limits by constructing a bionic body with good microstructure. The developed sensor incorporates hierarchical microstructures and interlocked architectures, which complement each other to improve the sensor's sensing performance. The enhancement effect of microstructure on sensor sensitivity was studied by comparative experiments. Experimental results show that the eggshell‐inspired bionic flexible sensor in this study has a high sensitivity of 15.01 kPa⁻¹ and a low detection limit (~4 Pa). In addition, the bionic sensor has a rapid response time (~180 ms) and excellent durability (~1000 cycles), making it a reliable platform for human body detection, dynamic load, and sound monitoring. This study provides great potential for innovative applications of bionic flexible sensors in electronic skin and sound monitoring. Highlights Hierarchical and interlocked microstructure enables the low detection limit. A wide range of applications in weak physiological signals. Effectively detect and distinguish different sounds. A sustainable strategy to convert wasted resources into functional materials.