Fluorescent Tetraphenylethylene-Based Europium Metal-Organic Framework for White-Light-Emitting Diodes

A luminescent europium-based metal-organic framework (Eu-MOF), designated as SYNU-4, has been synthesized. This MOF employs a tetraphenylethylene derivative ligand that exhibits aggregation-induced emission (AIE) characteristics. Comprehensive structural analyses reveal that SYNU-4 crystallizes in the orthorhombic system and boasts remarkable thermal stability. Optical evaluations demonstrate a subtle antenna effect in SYNU-4, attributable to the proximate energy levels between the ligand's triplet state and the Eu³⁺ excited state. Notably, it presents a fluorescence quantum yield of 10.46% and maintains consistent luminescence properties across a wide temperature spectrum. When integrated into ultraviolet-light-emitting diode (UV-LED) chips in conjunction with commercial yellow and red phosphors, the SYNU-4-augmented white-light-emitting diode (WLED) displays a white emission, achieving desirable color coordinates (0.33, 0.34), a correlated color temperature of 5620 K, and an impressive color rendering index of 86.9. These findings highlight the potential of SYNU-4 as a promising candidate for high-performance solid-state lighting.