A Dynamic Liquid Metal Bridging Strategy for Intrinsically Stretchable OLEDs

The performance of intrinsically stretchable organic light‐emitting diodes ( is ‐OLEDs) is inherently constrained by the trade‐off between the high conductivity and reflectivity of metal cathodes and their mechanical brittleness. Here, we introduce a dynamic liquid metal bridging strategy by fabricating a silver/eutectic gallium‐indium (Ag/EGaIn) composite cathode. The composite electron transport layer functions as a seed layer, facilitating the formation of a continuous and ultrathin Ag film with strong adhesion. This film then acts as a substrate for the integration of EGaIn droplets, facilitating improved interfacial contact. Under tensile strain, the fluidity and high conductivity of EGaIn may help bridge microcracks in the Ag film, thereby preserving efficient electron injection and optical reflectivity. Apart from the dominant crack‐bridging effect of EGaIn, minor localized Ag‐Ga interfacial alloying may also partially contribute to the stabilized electrical properties during stretching. Concurrently, blending the emissive polymer with the nonpolar thermoplastic elastomer styrene‐ethylene‐butylene‐styrene (SEBS) yields a high‐performance intrinsically stretchable emissive layer with a heterogeneous morphology. The resulting devices achieve a maximum luminance of 11 800 cd/m 2 and a current efficiency of 10.1 cd/A, maintaining uniform electroluminescence under 80% strain. This strategy was demonstrated in red, green, and blue devices, suggesting potential for multicolor stretchable displays.