High light electroluminescence of novel Cu(I) complexes

Three novel Cu(I) complexes, [CuDPEphos(NN)]BF4, where NN=1-(4-5′-phenyl-1,3,4-oxadiazolylbenzyl)-2-pyridinylbenzoimidazole (OXD–Pybm; L1) (1), 1-(4-carbazolylbutyl)-2-pyridinylbenzimidazole (Carl–Pybm; L2) (2), and 1-H-2-pyridinylbenzimidazole (HPybm; L3) (3), were synthesized. The photoluminescent (PL) properties of 1–3 and the electroluminescent (EL) properties of complexes 1 and 2 were systematically studied. The maximum brightness of 2-based devices was 8669 cd/m2, which should be the best among the reported Cu(I) complexes-based devices.