Patent ID: 6902833

Claim:
A device, comprising: an anode; a cathode; an first organic layer disposed between the anode and the cathode, wherein the first organic layer is capable of phosphorescent emissive when a voltage is applied between the anode and the cathode; a second organic layer disposed between the first organic layer and the cathode, wherein the second organic layer is in direct contact with the first organic layer, and wherein the second organic layer comprises a material having the structure: wherein: M is a metal selected from the group consisting of Ti, Zr, Hf, Nb, Re, Sn and Ge; R1, R2, R3, R4, R5, R6, R7 and R8 each represent no substitution, mono-, di-, or tri-substitution, and wherein the substituents are independently selected from the group consisting of: alkyl and aryl groups.