Hierarchically Integrated MOF‐CNT Buckypaper for Ultrasensitive and Broad‐Strain Wearable Sensors

ABSTRACT Flexible and highly sensitive strain sensors are essential for real‐time health monitoring, soft robotics, and next‐generation wearables requiring accurate wide‐range strain detection. Here, a highly flexible, ultrasensitive and mechanically robust strain sensor is developed using a composite buckypaper of silver‐based metal–organic framework (MOF) and carbon nanotubes (CNTs). The interconnected CNTs form conductive pathways that maintain stable electrical transport even under large strain, while MOF particles stabilize interfacial junctions, enhance strain sensitivity and preserve the structural integrity during stretching. These synergistic effects result in a highly conductive and responsive sensing network capable of detecting both small and large strain deformations. The best sensor exhibits an overall ultrawide strain detection range of up to ∼630%, with a high overall gauge factor of ∼4700 (R ² = 0.84). Remarkably, at higher strains (∼480%–630%), it achieves an exceptional gauge factor of ∼12150 with excellent linearity (R ² = 0.98), along with excellent durability over ∼1000 stretching‐releasing cycles at low as well as at high cyclic strain with minor response lag. The sensor prepared from these materials effectively detects diverse human motions, from subtle physiological signals to pronounced joint movements, highlighting its strong potential for wearable electronics and real‐time health monitoring applications.