Hole transport composition without luminance quenching

1. A hole transport composition comprising (a) an inert matrix polymer and (b) at least 10% by weight, based on the total weight of the composition, of a cyclometalated iridium complex; wherein the hole transport composition does not cause luminance quenching.

2. The hole transport composition of claim 1 , wherein the inert matrix polymer has a hole mobility less than 10 −6 cm 2 /(s·V).

3. The hole transport composition of claim 1 , wherein the inert matrix polymer has a band gap greater than 2.8 eV.

4. The hole transport composition of claim 1 , wherein the inert matrix polymer has a first triplet energy greater than 2.6 eV.

5. The hole transport composition of claim 1 , wherein the inert matrix polymer has a local dipole moment less than 5 debye.

6. The hole transport composition of claim 1 , wherein the inert matrix polymer is selected from the group consisting of polystyrenes, polycarbonates, polydienes, polyakylacrylates, polyolefins, polysiloxanes, fluoropolymers, polytetrafluoroethylenes, polyvinylidene fluorides, poly(ethylene glycol), poly(ethylene oxide), their co-polymers, substituted derivatives, and deuterated analogs thereof.

7. The hole transport composition of claim 1 , wherein the inert matrix polymer is selected from the group consisting of polystyrenes, substituted polystyrenes, and deuterated analogs thereof.

8. The hole transport composition of claim 1 , wherein the concentration of the cyclometalated iridium complex is 20-80% by weight, based on the total weight of the composition.

9. The hole transport composition of claim 1 , wherein the concentration of the cyclometalated iridium complex is 30-70% by weight, based on the total weight of the composition.

10. The hole transport composition of claim 1 , wherein the cyclometalated iridium complex has the formula Ir(L1)a(L2)b(L3)c;

where

L1 is the same or different at each occurrence and is a monoanionic bidentate cyclometalating ligand coordinated through carbon and nitrogen;

L2 is the same or different at each occurrence and is a monoanionic bidentate ligand which is not coordinated through a carbon;

L3 is the same or different at each occurrence and is a monodentate ligand;

a is 1-3;

b and c are independently 0-2; and

a, b, and c are selected such that the iridium is hexacoordinate and the complex is electrically neutral.

11. The hole transport composition of claim 1 , wherein the cyclometalated iridium complex is mixed with the inert matrix polymer.

12. The hole transport composition of claim 1 , wherein the cyclometalated iridium complex is bound to the inert matrix polymer by covalent bonds.

13. An electronic device comprising, in order, anode, hole transport layer, photoactive layer, cathode, wherein the hole transport layer comprises: (a) an inert matrix polymer and (b) at least 10% by weight, based on the total weight of the composition, of a cyclometalated iridium complex; and wherein the hole transport layer does not cause luminance quenching.

14. The electronic device of claim 13 , wherein the hole transport layer consists essentially of: (a) an inert matrix polymer and (b) at least 10% by weight, based on the total weight of the composition, of a cyclometalated iridium complex.

15. The hole transport composition of claim 1 , wherein the inert polymer matrix is deuterated.