Terpyridine-Based Metal–Organic Cage with Enhanced Emission via Coordination-Induced Rigidity

Realizing the regulation of photophysical properties by precisely controlling the molecular composition and configuration, thereby obtaining high-performance optical materials, remains of great significance. Due to the directionality and reversibility of the coordination bond, coordination-driven self-assembly endows the molecule with customized thermodynamically stable structures and desired properties. In this paper, a luminous metal-organic cage [Zn₁₂L₆] (<b>S</b>) was elaborately designed and quantitatively synthesized by self-assembly of tetrapodal TQPP chromophore-containing terpyridine ligand <b>L</b> with Zn²⁺. Complex <b>S</b> possessed a rigid cage-like structure, which endows a higher fluorescence quantum efficiency both in solution (∼88%) and neat solid (16%) than the corresponding ligand <b>L</b>. Further, using complex <b>S</b> as the photoactive component, two light-emitting diodes (LEDs) were successfully fabricated and the emission of pure white light (CIE coordinates: 0.3341, 0.3300) was achieved. These results afford a method to obtain enhanced luminescence performance via the formation of rigid coordination-driven supramolecular architectures.