High‐Efficiency Violet‐Light‐Emitting Materials Based on Phenanthro[9,10‐d]imidazole

Novel violet: The material M2 (see picture), which is based on phenanthro[9,10-d]imidazole and carbazole, has a narrow band in the electroluminescence emission spectrum that results in saturated violet-light emission. The CIE of a non-doped device can reach (0.166, 0.056) with an external efficiency of 3.02 %.