Performance enhancement layer for OLED devices

1. An organic light-emitting device comprising:

a) a substrate;

b) a first electrode and a second electrode positioned relative to the substrate in which at least one of the electrodes is the transparent electrode;

c) an organic light-emitting element including at least a light-emitting layer disposed between the two electrodes; and

d) a performance enhancement layer disposed between the two electrodes; wherein the performance enhancement layer is high index of at least 0.1 larger than that of the transparent electrode, has a thickness of at least 20 nm wherein the through-thickness electrical resistance of the performance enhancement layer is higher than 10 −4 ohm-cm 2 and less than 100 ohm-cm 2 , and comprises a mixture of one or more metal oxides and one or more metal sulfides.

2. The device of claim 1 wherein the performance enhancement layer is located between the transparent electrode and the organic light emitting element.

3. The device of claim 1 wherein the organic light emitting element further includes a charge-injection layer disposed between the organic light-emitting element and the performance enhancement layer.

4. The device of claim 1 wherein the performance enhancement layer is low absorption.

5. The device of claim 1 wherein the metal oxides are selected from indium oxide, gallium oxide, zinc oxide, tin oxide, molybdenum oxide, vanadium oxide, antimony oxide, bismuth oxide, zinc oxide, tantalum oxide, tungsten oxide, niobium oxide, or nickel oxide and the metal sulfide is zinc sulfide.