Organic semiconductor doping process
View Patent ↗The present invention relates to the doping of organic semiconductors and processes for producing layers of p-doped organic semiconductors. Disclosed is a process for p-doping organic semiconductors comprising treating the organic semiconductor with an oxidized salt of the organic semiconductor. A process for producing a layer of a p-doped organic semiconductor comprising producing a p-doped organic semiconductor by treating the organic semiconductor with an oxidized salt of the organic semiconductor; disposing a composition comprising a solvent and the p-doped organic semiconductor on a substrate; and removing the solvent is also described. Also disclosed is a process for producing a layer of a p-doped organic semiconductor comprising: disposing a composition comprising a solvent, the organic semiconductor and a protic ionic liquid on a substrate; and removing the solvent. A process for producing a semiconductor device comprising a process for doping an organic semiconductor according to the invention is also described. Finally, a high purity p-dopant composition is described.
1. A process for producing a p-doped organic semiconductor comprising treating an organic semiconductor with a composition comprising an oxidised salt of the organic semiconductor, which oxidised salt of the organic semiconductor is a salt of formula [OS][A], wherein OS is a cation of an organic semiconductor and A is ClO 4 − , NO 3 − or an anion of formula (i), (ii), (iii) or (iv)
wherein each X is the same or different and is an electron withdrawing group.
2. A process according to claim 1 which comprises treating the organic semiconductor with a composition comprising from 80 to 100 wt % of the oxidised salt of the organic semiconductor.
3. A process according to claim 1 wherein the organic semiconductor comprises:
an organic semiconductor comprising a triarylamine moiety, an organic semiconductor comprising a conjugated polymer, an organic semiconductor comprising a conjugated oligomer, or an organic semiconductor comprising a polycyclic aromatic hydrocarbon.
4. A process according to claim 1 wherein the organic semiconductor comprises a compound of formula (V), (I), (II), (III), (IV), (VI) or (VII):
wherein:
each A 1 is the same or different and is an unsubstituted or substituted aryl ring or an unsubstituted or substituted heteroaryl ring;
L is a conjugated linker;
n is 3 or 4; and
m is an integer of 2 or more.
5. A process according to claim 1 wherein the organic semiconductor comprises unsubstituted or substituted polythiophene or an unsubstituted or substituted oligothiophene.
6. A process according to claim 1 wherein the organic semiconductor comprises a compound of formula (V) or (Vb):
wherein each A 1 is the same or different and is an unsubstituted or substituted aryl ring or an unsubstituted or substituted heteroaryl ring;
wherein each R 1 is the same or different and is a group selected from hydrogen, C 1-8 alkyl, C 2-8 alkenyl, C 2-8 alkynyl, C 1-8 alkoxy, hydroxyl, mono-C 1-8 alkylamino, di-C 1-8 alkylamino, amino, halide, cyano, nitro, and thiol.
7. A process according to claim 1 wherein A is bis(trifluoromethanesulfonyl)imide, bis(pentafluoroethanesulfonyl)imide, bis(perfluoropropanesulfonyl)imide, trifluoroacetate, or trifluoromethanesulfonate.
8. A process according to claim 1 wherein the process further comprises producing the oxidised salt of the organic semiconductor by a process comprising:
(a) treating the organic semiconductor with an oxidant to produce an oxidation product;
(b) isolating the oxidation product;
(c) performing an anion exchange with A on the oxidation product to produce an oxidised salt of the organic semiconductor comprising A, wherein A is as defined in claim 1 and
(d) isolating the oxidised salt of the organic semiconductor.
9. A process according to claim 8 wherein the oxidant comprises
a compound selected from percyanocarbon compounds, quinone compounds, chloroquinone compounds, halogen compounds or interhalogen compounds;
a cation selected from triarylaminium radical cations, heterocyclic radical cations, triarylcarbenium cations, tropylium cations, complex cations of metals or nitrosonium cation; or
an anion selected from a hexacyanotrimethylenecyclopropane radical anion [C 3 {C(CN) 2 } 3 ] − , or a hexachloroplatinate anion [PtCl 6 ] 2− .
10. A process according to claim 8 wherein the oxidant comprises
a compound selected from TCNE, TCNQ, F4TCNQ, DDQ, 1,2-benzoquinone, 1,4-benzoquinone, 1,4-napthoquinone, dichlorobenzoquinone, chloranil, fluorine, chlorine, bromine, or iodine; or
a cation selected from [NAr 3 ] + , thianthrene cation, phenoxathiin cation, phenothiazine cation, N-methylphenothiazine cation, N-phenylphenothiazine cation, [CAr 3 ] + , [Ru(phen) 3 ] 3+ , [Fe(bipy) 3 ] 3+ , [Fe(η-C 5 H 4 COMe) 2 ] + , [Fe(η-C 5 H 4 COMe)Cp] + , or [FeCp 2 ] + ;
wherein Ar is an unsubstituted or substituted aryl group.
11. A process according to claim 8 wherein the oxidant comprises a cation selected from [N(4-C 6 H 4 Br) 3 ] + , [N(2,4-C 6 H 3 Br 2 ) 3 ] + , [N(2,4,6-C 6 H 2 Br 3 ) 3 ] + , N(4- C 6 H 4 Cl) 3 ] + , [N(2,4-C 6 H 3 Cl 2 ) 3 ] + , [N(2,4,6-C 6 H 2 Cl 3 ) 3 ] + , [N(C 6 Cl 5 ) 3 ] + , [N(4C 6 H 4 - CN) 3 ] + , [N(4-C 6 H 4 CO 2 Me) 3 ] + , [N(4-C 6 H 4 Me) 3 ] + , [N(4-C 6 H 4 OMe) 3 ] + , or [N(4-C 6 H 4 NO 2 ) 3 ] + .
12. A process according to claim 8 wherein the oxidant comprises an anion selected from [SbCl 6 ] − , [BCl 4 ] − , [AlCl 4 ] − , [PF 6 ] − , [SbF 6 ] − , [BF 4 ] − , [AlF 4 ] − , [ClO 4 ] − , or [NO 3 ] − .
13. A process according to claim 8 wherein the oxidant comprises [N(4-C 6 H 4 Br) 3 ][SbCl 6 ] or [N(4-C 6 H 4 Br) 3 ][SbF 6 ].
14. A process according to claim 8 wherein the amount of the oxidant is from 1 to 2 equivalents relative to the amount of the organic semiconductor.
15. A process according to claim 8 wherein (c) comprises treating the oxidation product with a salt comprising A.
16. A process according to claim 8 wherein (c) comprises treating the oxidation product with a salt of formula [M][A], wherein M is a cation selected from metal cations, ammonium cations or a sulfonium cation.
17. A process according to claim 16 wherein M is selected from Li + , Na + , K + , Be 2+ , Mg 2+ , Ca 2+ , Ag + or Zn 2+ .
18. A process according to claim 8 wherein (c) comprises treating the oxidation product with a salt selected from LiTFSI, NaTFSI, KTFSI, AgTFSI, Zn(TFSI) 2 , LiBETI, NaBETI, KBETI, AgBETI, Zn(BETI) 2 .
19. A process according to claim 8 wherein (c) comprises treating the oxidation product with 10 to 30 equivalents of a salt comprising the anion A.
20. A process according to claim 1 wherein the organic semiconductor is treated with from 0.1 to 50 mol % of the oxidised salt of the organic semiconductor relative to the amount of the organic semiconductor.
21. The process of claim 1 , wherein wherein X is CF 3 or CF 2 CF 3 .
22. A process for producing a layer of p-doped organic semiconductor comprising:
(a) producing a p-doped organic semiconductor by a process comprising treating an organic semiconductor with a composition comprising an oxidised salt of the organic semiconductor, which oxidised salt of the organic semiconductor is a salt of formula [OS][A], wherein OS is a cation of an organic semiconductor and A is ClO 4 − , NO 3 − or an anion of formula (i), (ii), (iii) or (iv)
wherein each X is the same or different and is an electron withdrawing group;
(b) disposing on a substrate a composition comprising a solvent and the p-doped organic semiconductor; and
(c) removing the solvent.
23. A process according to claim 22 wherein the composition disposed on the substrate further comprises LiTFSI and/or tert-butyl pyridine.
24. A process according to claim 23 wherein the composition comprises from 1 to 40 mol % LiTFSI and from 50 to 150 mol % tert-butyl pyridine relative to the amount of the organic semiconductor.
25. A process according to claim 22 wherein the solvent comprises acetonitrile and/or chlorobenzene.
26. A process according to claim 22 wherein the substrate comprises an electrode material or a semiconductor material or a mesoporous layer of a semiconductor material or a mesoporous layer of a dielectric material.
27. A layer of a p-doped organic semiconductor obtainable by a process according to claim 22 .
28. A semiconductor device which comprises a layer of a p-doped organic semiconductor, wherein the layer of a p-doped organic semiconductor is as defined in claim 27 .
29. The process of claim 22 , wherein wherein X is CF 3 or CF 2 CF 3 .
30. A process for producing a semiconductor device comprising
a step of producing a p-doped organic semiconductor by a process comprising treating an organic semiconductor with a composition comprising an oxidised salt of the organic semiconductor, which oxidised salt of the organic semiconductor is a salt of formula [OS][A], wherein OS is a cation of an organic semiconductor and A is ClO 4 − , NO 3 − or an anion of formula (i), (ii), (iii) or (iv)
wherein each X is the same or different and is an electron withdrawing group; or
a step of producing a layer of a p-doped organic semiconductor by a process comprising:
(a) producing a p-doped organic semiconductor by a process comprising treating an organic semiconductor with a composition comprising an oxidised salt of the organic semiconductor, which oxidised salt of the organic semiconductor is a salt of formula [OS][A], wherein OS is a cation of an organic semiconductor and A is ClO 4 − , NO 3 − or an anion of formula (i), (ii), (iii) or (iv)
wherein each X is the same or different and is an electron withdrawing group;
(b) disposing on a substrate a composition comprising a solvent and the p-doped organic semiconductor; and
(c) removing the solvent.
31. A process according to claim 30 wherein the process comprises:
(a) disposing on a first electrode material at least one layer of a semiconductor material to produce a resulting substrate comprising a first electrode material and at least one layer of a semiconductor material;
(b) sensitizing the resulting substrate to produce a sensitized substrate; and
(c) producing a layer of a p-doped organic semiconductor by a process according to claim 27 on the sensitized substrate, or
producing a p-doped organic semiconductor by a process according to claim 27 and forming a layer of the p-doped organic semiconductor thus produced on the sensitized substrate.
32. A process according to claim 31 wherein (a) comprises disposing on a first electrode material a compact layer of a semiconductor material and/or a mesoporous layer of a semiconductor material.
33. A process according claim 31 wherein the first electrode material comprises a transparent conducting oxide.
34. A process according to claim 31 wherein (b) comprises treating the resulting substrate comprising a first electrode material and at least one layer of a semiconductor material with a dye or a semiconducting perovskite.
35. A process according to claim 31 which further comprises:
(d) disposing a second electrode material on the layer of a p-doped organic semiconductor.
36. A process according to claim 30 wherein the device is any of an optoelectronic device, a photovoltaic device, a solar cell, a photo detector, a light-sensitive transistor, a capacitor, a super-capacitor, a phototransistor, a solid-state triode, a battery, a battery electrode, a light-emitting device, a light-emitting diode a dye-sensitized solar cell, a perovskite-sensitized solar cell, a quantum dot sensitized solar cell, an extremely thin absorber cell or a meso-super structured solar cell.
37. A semiconductor device obtainable by a process according to claim 30 .
38. The process of claim 30 , wherein wherein X is CF 3 or CF 2 CF 3 .
39. A composition which comprises from 50 to 100 wt % of an oxidised salt of an organic semiconductor according to formula (VIII)
wherein each A 1 is the same or different and is an unsubstituted or substituted aryl ring or an unsubstituted or substituted heteroaryl ring; and
X is a C 1-8 -haloalkyl group.
40. A composition according to claim 39 wherein the composition comprises from 80 to 100 wt % of the oxidised salt of the organic semiconductor.
41. A composition according to claim 39 wherein the oxidised salt of the organic semiconductor is [2,2-7,7-tetrakis(N,N-di-pmethoxyphenylamine)-9,9-spirobifluorene] + [TFSI] − or [2,2-7,7-tetrakis(N,N-di-pmethoxyphenylamine)-9,9-spirobifluorene] + [BETI] − .