An organic light emitting device comprising a heterostructure for producing electro-luminescence. The heterostructure has a charge carrier layer that includes a compound having molecules having at least one electron transporting moiety that is a 2-methyl-8-quinolinolato ligand coordinated with a metal chosen from the group Al, Ga, and In, and at least one hole transporting moiety. For example, the compound may be bis(2-methyl-8-quinolinolato)[p-(N-phenyl-2-naphthylamino)phenolato]aluminum(III), bis(2-methyl-g-quinolinolato)p-carbazolphenolato)aluminum(III), or bis(2-methyl-8-quinolinolato)(m-carbazolphenolato)aluminum(III).