The OLEDs with mer-Ir(tfpi_Bn)3 and mer-Ir(tfpi_tmBn)3 both satisfy the National Television System Committee (NTSC) standard for the primary blue (CIEy of 0.08). Our devices show amongst the best performance of deep blue OLEDs (CIEy < 0.1) with Ir(C^C)3 complexes as emitters (c.f. Figure ). Finally, the optimization of the device architecture described here highlights the importance of host material, electron blocking layer, and doping profile of the EML on the performance of OLEDs. With the optimized device structure, deep blue emission with lEL of 429 nm and CIE coordinates of (0.16, 0.08) was observed, which is close to the BT.2020 standard. The EQEmax (EQE100) is 14.9% (11.7%), and 12.2% (11%) for the mer-Ir(tfpi_tmBn)3 and mer-Ir(tfpi_Bn)3 OLEDs. These results underscore the value of incorporating bulky N-Bn or N-tmBn groups to the ligands in deep-blue emitting iridium NHC complexes.