Blue fluorescent Zinc(II) complexes bearing schiff base ligand for solution-processed organic light-emitting diodes with CIEy ≤ 0.09

Inspired by the blue fluorescent feature of metal schiff-base complexes, we have been successfully synthesized the blue fluorescent Zn(II) complexes ( Zn-1 and Zn-2 ) bearing pyrazolone based azomethine ligands. The photophysical and electrochemical properties of these complexes have been investigated by several techniques in detail. Both complexes showed the emission in blue region and exhibited a good thermal stability. The single crystal X-ray structure analysis were performed to explicate their coordination adjustment around the Zn(II) metal ion. DFT and TDDFT methods performed to understand the involvement of metal ions and Schiff base ligand in the formation of frontier orbitals. For application in organic light emitting diodes, electroluminescent devices were fabricated by using simple solution-processed fabrication method. The best performance was observed at a low turn-on voltage of 3.5 V with a maximum external quantum efficacy of 3.2% for a deep-blue emission at a CIE y of 0.09. • Cost effective and eco-friendly homoleptic Zn(II) Schiff base complexes observed deep blue electroluminescence with simple solution-processing method can achieve the best performance with a low turn-on voltage of 3.5 V and a maximum external quantum efficacy (EQEmax) of 3.2% at a CIEy of 0.09. • The structural features make both complexes distinct in terms of their photophysical and electrochemical behaviours.