High-elastic Eu³⁺/Tb³⁺ complex@TPU flexible fibers for intelligent sensing and dynamic identifying

Lanthanide-organic complexes showcase significant potential in developing advanced light-emitting and sensing functional systems for next-generation wearable electronics devices. Nevertheless, achieving autonomous efficient and stable light emission while ensuring its seamless incorporation into flexible textile platforms continues to pose a considerable challenge. In this work, rare-earth complex luminescent fibers (RCLFs) by doping Eu³⁺/Tb³⁺ complexes into thermoplastic polyurethane are successfully prepared via a simple and eco-friendly wet spinning process. The elongation at break up to 750 % confirms their remarkable mechanical properties, at the same time, the photoluminescence quantum yield of 65.19 % verifies the efficient luminescence emission. Especially, the broad stress sensitivity of 1.07 ± 0.02 % mm⁻¹ and ultrahigh thermal sensitivity of 1.35 ± 0.01 % K⁻¹ reveal the potential of the RCLFs as smart sensors. In this study, the wet-spun RCLFs integrate colorful luminescence with stimulus-responsive characteristics to mechanical strain and temperature variations, demonstrating tremendous potential for next-generation flexible optoelectronic systems.