Highly efficient non-doped deep-blue organic light-emitting diodes by employing a highly rigid skeleton

Two novel deep-blue emitters based on a highly rigid unit, IDC-PA and IDC-Py, were prepared by respectively introducing the 7,7-dimethyl-5-phenyl-5,7-dihydro indeno [2,1-b] carbazole (IDC) unit with anthracene and pyrene derivatives. The emitters exhibit high quantum efficiency, excellent thermal stability, narrow full width at half maximum and deep-blue emission. Moreover, the IDC-PA and IDC-Py-based devices demonstrated maximum EQEs of 4.41% and 6.08% and maintain 4.35% and 5.35% as applied in non-doped devices even at the brightness of 5000 cd m−2 with CIE coordinates of (0.15, 0.10) and (0.15, 0.08), respectively.