Achieving NIR emission for tetradentate platinum (II) salophen complexes by attaching dual donor-accepter frameworks in the heads of salophen

Two novel tetradentate platinum (II) salophen complexes A and B appending dual donor (D)-accepter (A) frameworks were synthesized and characterized. Using both platinum (II) complexes as a single dopant and a blend of PVK and OXD-7 as host matrix, the made polymer light-emitting devices exhibited a deep red emission at 651 nm with an external quantum efficiency (EQE) of 0.1% and radiant (R) intensity of 17 μW cm−2 for the complex A, but a near-infrared emission at 695 nm with a EQE of 1.36% and a R of 45 μW cm−2 for the complex B. It demonstrates that appending the dual D-A chains into the 1,4-phenylene head of the salophen can significantly improve electroluminescent properties for their Pt (II) complexes.196