An unprecedented {Y2⊂Y10} type disk-like Y12 nanocluster featuring electroluminescence property in OLED device

Abstract

Although great efforts have been made to explore the exquisite rare-earth (RE) clusters, the design and construction of planar RE clusters with disk-like geometrical features are still scarce. Herein, a novel disk-like RE-cluster Y₁₂ (abbreviated as 1), formulated as [Y₁₂(L)₁₀(CO₃)₄(NO₃)₂(μ₃-OH)₆] (H₂L = 7,7′-(2-methylmethylene)bis(8-quinolonol)) was synthesized successfully under solvothermal conditions. Owing to the template effect and fruitful coordination modes of NO₃⁻, a novel Y₂⊂Y₁₀ type structure with dual-core in the center position of the cluster, which distinguishes it from the traditional brucite-type disk-like RE-cluster was achieved. Based on the ESI-MS analysis, the possible assembly mechanism of Y₅ → Y₈ → Y₁₂ is proposed. The luminescence investigation illustrates that this cluster not only shows green emission in solid-state and common organic solvents but also has obvious electroluminescent performance, which can be used as the emitting layer in organic light-emitting diodes (OLEDs).