Material for a hole transport layer with p-dopant

1. A solution to form a hole transport layer, the solution comprising:

a solvent;

a hole transporter matrix material dissolved in the solvent; and

a metallic doping agent dissolved in the solvent, the doping agent having a metallic central atom that can form a charge transfer complex with the matrix material wherein

the doping agent is selected from the group consisting of molybdenum oxides, tungsten oxides, vanadium oxides and rhenium oxides.

2. The solution according to claim 1 , wherein the matrix material is formed from at least one non-polymeric hole transporter selected from the group consisting of N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-9,9-dimethyl-fluorene, N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)-9,9-diphenyl-fluorene, N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-9,9-diphenyl-fluorene, N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2-dimethylbenzidine, N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)-9,9-spirobifluorene, 2,2′,7,7′-tetrakis(N,N-diphenylamino)-9,9′-spirobifluorene, N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-benzidine, N,N′-bis(naphthalen-2-yl)-N,N′-bis(phenyl)-benzidine, N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)-benzidine, N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)-9,9-dimethyl-fluorene, N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-9,9-spirobifluorene, di-[4-(N,N-ditolyl-amino)-phenyl]cyclohexane, 2,2′,7,7′-tetra(N,N-di-tolyl)amino-spiro-bifluorene, 9,9-bis[4-(N,N-bis-biphenyl-4-yl-amino)phenyl]-9H-fluorene, 2,2′,7,7′-tetrakis[N-naphthalenyl(phenyl)-amino]-9,9-spirobifluorene, 2,7-bis[N,N-bis(9,9-spiro-bifluorene-2-yl)-amino]-9,9-spirobifluorene, 2,2′-bis[N,N-bis(biphenyl-4-yl)amino]-9,9-spirobifluorene, N,N′-bis(phenanthren-9-yl)-N,N′-bis(phenyl)-benzidine, N,N,N′,N′-tetra-naphthalen-2-yl-benzidine, 2,2′-bis(N,N-di-phenyl-amino)-9,9-spirobifluorene, 9,9-bis[4-(N,N-bis-naphthalen-2-yl-amino)phenyl]-9H-fluorene, 9,9-bis[4-(N,N′-bis-naphthalen-2-yl-N,N′-bis-phenyl-amino)-phenyl]-9H-fluorene, titanium oxide phthalocyanine, copper phthalocyanine, 2,3,5,6-tetrafluoro-7,7,8,8,-tetracyano-quinodimethane, 4,4′,4″-tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine, 4,4′,4″-tris(N-(2-naphthyl)-N-phenyl-amino)triphenylamine, 4,4′,4″-tris(N-(1-naphthyl)-N-phenyl-amino)triphenylamine, 4,4′,4″-tris(N,N-diphenyl-amino)triphenylamine, pyrazino[2,3-f][1,10]phenanthroline-2,3-dicarbonitrile, N,N,N′,N′-tetrakis(4-methoxyphenyl)benzidine, 2,7-bis[N,N-bis(4-methoxy-phenyl)amino]-9,9-spirobifluorene, 2,2′-bis[N,N-bis(4-methoxy-phenyl)amino]-9,9-spirobifluorene, N,N′-di(naphthalen-2-yl)-N,N′-diphenylbenzene-1,4-diamine, N,N′-di-phenyl-N,N′-di-[4-(N,N-di-tolyl-amino)phenyl]benzidine, N,N′-di-phenyl-N,N′-di-[4-(N,N-di-phenyl-amino)phenyl]benzidine, and N′-diphenyl-N,N′-bis[1-naphthyl-1,1′-biphenyl]-4,4′-diamine (NBP).

3. The solution according to claim 1 , wherein the matrix material is formed from at least one polymeric hole transporter selected from the group consisting of (poly-(3,4-ethylenedioxythiophene) (PEDOT), polyvinylcarbazole (PVK), poly(N,N′-bis,(4-butylphenyl)-N,N′-bis(phenyl)benzidine (PTPD), polyaniline (PANI), poly(3-hexylthiophene) (P3HT) and copolymers thereof.

4. The solution according to claim 1 , wherein the matrix material is formed from a combination of poly(N,N′-bis,(4-butylphenyl)-N,N′-bis(phenyl)benzidine (PTPD) and N′-diphenyl-N,N′-bis[1-naphthyl-1,1-biphenyl]-4,4′-diamine (NPB).

5. The solution according to claim 1 , wherein the doping agent is rhenium heptoxide (Re 2 O 7 ).

6. The solution according to claim 1 , wherein

the matrix material is formed from a combination of poly(N,N′-bis,(4-butylphenyl)-N,N′-bis(phenyl)benzidine (PTPD) and N′-diphenyl-N,N′-bis[1-naphthyl-1,1-biphenyl]-4,4′-diamine (NPB), and

the doping agent is rhenium heptoxide (Re 2 O 7 ).

7. The solution as claimed in claim 1 , wherein a mixture of solvents are used to form the solution.

8. The solution as claimed in claim 1 , wherein the solution contains the charge transfer complex of the metal central element with the matrix material.

9. A method for producing a hole transport layer, comprising:

applying a solution onto a lower electrode layer, the solution containing a hole transporter matrix material and a doping agent compound, both dissolved in a solvent, the doping agent compound having a metallic central atom; and

after applying the solution, removing the solvent by thermolysis such that the metallic central atom forms a charge transfer complex with the matrix material to transport positive charges, wherein

the doping agent is selected from the group consisting of molybdenum oxides, tungsten oxides, vanadium oxides and rhenium oxides.

10. The method according to claim 9 , wherein the matrix material is formed from at least one non-polymeric hole transporter selected from the group consisting of N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-9,9-dimethyl-fluorene, N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)-9,9-diphenyl-fluorene, N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-9,9-diphenyl-fluorene, N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-2,2-dimethylbenzidine, N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)-9,9-spirobifluorene, 2,2′,7,7′-tetrakis(N,N-diphenylamino)-9,9′-spirobifluorene, N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-benzidine, N,N′-bis(naphthalen-2-yl)-N,N′-bis(phenyl)-benzidine, N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)-benzidine, N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)-9,9-dimethyl-fluorene, N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-9,9-spirobifluorene, di-[4-(N,N-ditolyl-amino)-phenyl]cyclohexane, 2,2′,7,7′-tetra(N,N-di-tolyl)amino-spiro-bifluorene, 9,9-bis[4-(N,N-bis-biphenyl-4-yl-amino)phenyl]-9H-fluorene, 2,2′,7,7′-tetrakis[N-naphthalenyl(phenyl)-amino]-9,9-spirobifluorene, 2,7-bis[N,N-bis(9,9-spiro-bifluorene-2-yl)-amino]-9,9-spirobifluorene, 2,2′-bis[N,N-bis(biphenyl-4-yl)amino]-9,9-spirobifluorene, N,N′-bis(phenanthren-9-yl)-N,N′-bis(phenyl)-benzidine, N,N,N′,N′-tetra-naphthalen-2-yl-benzidine, 2,2′-bis(N,N-di-phenyl-amino)-9,9-spirobifluorene, 9,9-bis[4-(N,N-bis-naphthalen-2-yl-amino)phenyl]-9H-fluorene, 9,9-bis[4-(N,N′-bis-naphthalen-2-yl-N,N′-bis-phenyl-amino)-phenyl]-9H-fluorene, titanium oxide phthalocyanine, copper phthalocyanine, 2,3,5,6-tetrafluoro-7,7,8,8,-tetracyano-quinodimethane, 4,4′,4″-tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine, 4,4′,4″-tris(N-(2-naphthyl)-N-phenyl-amino)triphenylamine, 4,4′,4″-tris(N-(1-naphthyl)-N-phenyl-amino)triphenylamine, 4,4′,4″-tris(N,N-diphenyl-amino)triphenylamine, pyrazino[2,3-f][1,10]phenanthroline-2,3-dicarbonitrile, N,N,N′,N′-tetrakis(4-methoxyphenyl)benzidine, 2,7-bis[N,N-bis(4-methoxy-phenyl)amino]-9,9-spirobifluorene, 2,2′-bis[N,N-bis(4-methoxy-phenyl)amino]-9,9-spirobifluorene, N,N′-di(naphthalen-2-yl)-N,N′-diphenylbenzene-1,4-diamine, N,N′-di-phenyl-N,N′-di-[4-(N,N-di-tolyl-amino)phenyl]benzidine, N,N′-di-phenyl-N,N′-di-[4-(N,N-di-phenyl-amino)phenyl]benzidine, and N′-diphenyl-N,N′-bis[1-naphthyl-1,1′-biphenyl]-4,4′-diamine (NBP).

11. The method according to claim 9 , wherein the matrix material is formed from at least one polymeric hole transporter selected from the group consisting of (poly-(3,4-ethylenedioxythiophene) (PEDOT), polyvinylcarbazole (PVK), poly(N,N′-bis,(4-butylphenyl)-N,N′-bis(phenyl)benzidine (PTPD), polyaniline (PANI), poly(3-hexylthiophene) (P3HT) and copolymers thereof.

12. The method according to claim 9 , wherein the matrix material is formed from a combination of poly(N,N′-bis,(4-butylphenyl)-N,N′-bis(phenyl)benzidine (PTPD) and N′-diphenyl-N,N′-bis[1-naphthyl-1,1′-biphenyl]-4,4′-diamine (NPB).

13. The method according to claim 9 , wherein the doping agent is rhenium heptoxide (Re 2 O 7 ).

14. The method according to claim 9 , wherein

the matrix material is formed from a combination of poly(N,N′-bis,(4-butylphenyl)-N,N′-bis(phenyl)benzidine (PTPD) and N′-diphenyl-N,N′-bis[1-naphthyl-1,1′-biphenyl]-4,4′-diamine (NPB), and

the doping agent is rhenium heptoxide (Re 2 O 7 ).