Synthesis, Structure, and Luminescence Properties of Zinc(II) Complex with a Spacer-Armed Tetradentate N2O2-Donor Schiff Base

A zinc complex bearing a pyrazolone-based azomethine ligand has been synthesized for blue-emitting organic light-emitting diodes (OLEDs). The azomethine ligand H2L and the complex [ZnL·H2O] were characterized by IR, 1H NMR, XRD, and TGA/DSC techniques. According to a single-crystal X-ray diffraction analysis, the complex [ZnL·H2O] has a molecular structure. Its solid-state PL maxima appear to be at 416 nm and emit moderate blue emission with a quantum yield (QY) of 2%, with a dehydrated form of the complex showing greater efficiency with a QY of 55.5%. ZnL-based electroluminescent devices for OLED applications were fabricated. The devices exhibit blue emission with brightness up to 5300 Cd/A.