A compound having the formula Ir(LA)n(LB)3-n is disclosed wherein LA is an aza-DBF ligand and LB is an alkyl-substituted phenylpyridine ligand, wherein the compound has a structure according to Formula I: wherein A1, A2, A3, A4, A5, A6, A7, and A8 comprise carbon or nitrogen; wherein at least one of A1, A2, A3, A4, A5, A6, A7, and A8 is nitrogen; wherein ring B is bonded to ring A through a C—C bond; wherein the iridium is bonded to ring A through a Ir—C bond; wherein X is O, S, or Se; wherein R1 and R2 each independently represent mono-, di-, tri-, tetra-substitution, or no substitution; wherein R′ and R″ each independently represent mono-, di-substitution, or no substitution; wherein any adjacent substitutions in R′, R″, R1, R2, R3, R4, R5, and R6 are optionally linked together to form a ring; wherein R1, R2, R′, and R″ are each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; wherein R3, R4, R5, and R6 are each independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof; wherein n is an integer from 1 to 3; and wherein total number of carbons in at least one of the pairs R3 and R4, and R5 and R6 is at least four.