Realization of High-Energy Emission from [Cu(N−N)(P−P)]⁺ Complexes for Organic Light-Emitting Diode Applications

In this paper, we propose a potential method leading to high-energy emitting Cu(I) complexes. Diimine ligands with high-π* and their corresponding [Cu(N−N)(P−P)]BF4 complexes are synthesized. Systematic research proves that the utilization of diimine ligands with high-π* is a practicable and effective method to lead to high-energy emission from [Cu(N−N)(P−P)]BF4 complexes. Efficient blue- and green-emitters are realized, and their electroluminescence (EL) performances are also investigated. A maximum brightness of 2850 cd/m2 is achieved for the blue-emitting EL device, with an emission peaking at 480 nm. Meanwhile, the green-emitting EL device reaches a maximum brightness of 2320 cd/m2, with an emission peaking at 532 nm.