Bio‐Inspired High‐Low Toughness Multilayer Mechanoluminescent Composite With Superior Mechanical Properties

ABSTRACT Polydimethylsiloxane confers stretchability, enhanced brightness, mechanical responsivity and self‐charging capability to mechanoluminescence materials, yet its intrinsic low toughness and crack resistance pose a major obstacle to the practical application of ML devices. Herein, high‐toughness silicone‐rubber layers were introduced to slice the ZnS:Cu@Al 2 O 3 /PDMS matrix into a multilayer architecture that mimics the hinged microstructure of clam. The modified composite exhibits a dramatic enhancement in stretchability, with fracture strain increasing from approximately 100% to 500%. This improvement is accompanied by more than a four‐fold boost in ultimate ML intensity, along with sustained durability demonstrated over 30 000 cycles at the tensile limit. The reduced layer thickness and suppressed crack propagation by the high‐toughness silicone‐rubber interlayer raise toughness from 0.95 to 4.93 MJ/m 3 . This work provides an effective strategy for enhancing the performance of PDMS‐based flexible ML composites, advancing their practicality and offering new insights for applications in stress visualization, intelligent information display, and mechanics sensing.