Efficient organic light-emitting diodes with narrow emission bandwidths based on iridium(iii) complexes with a pyrido[3′,2′:4,5]pyrrolo[3,2,1-jk]carbazole unit

Two iridium( iii ) complexes containing a bulk and rigid pyrido[3′,2′:4,5]pyrrolo[3,2,1- jk ]carbazole unit show a narrow FWHM bandwidth of about 30 nm in OLEDs with an EQE max of 24.5% and an efficiency roll-off of less than 5%.