Perovskite Material Layer Processing

• US 20150318477A1
• Filed: 07/10/2015
• Published: 11/05/2015
• Est. Priority Date: 11/26/2013
• Status: Active Grant

• Current Assignee: Cubicpv Incorporated
• Original Assignee: Michael D. Irwin
• Inventors: Irwin, Michael D., Chute, Jerred A., Dhas, Vivek V.
• Granted Patent: US 9,425,396 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C07B 2200/13 Crystalline forms, e.g. polymorphs
• CPC Class Codes: C07F 7/24 Lead compounds
• CPC Class Codes: C23C 14/06 characterised by the coating material C23C14/0021 , C23C14/04 take precedence
• CPC Class Codes: C23C 16/50 using electric discharges generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34
• CPC Class Codes: H01G 9/2031 comprising titanium oxide, e.g. TiO2 H01G9/2036 takes precedence
• CPC Class Codes: H01G 9/2059 comprising an organic dye as the active light absorbing material, e.g. adsorbed on an electrode or dissolved in solution
• CPC Class Codes: H01L 2031/0344 Organic materials
• CPC Class Codes: H01L 31/032 including, apart from doping materials or other impurities, only compounds not provided for in groups H01L31/0272 - H01L31/0312
• CPC Class Codes: H10K 2102/00 Constructional details relating to the organic devices covered by this subclass
• CPC Class Codes: H10K 2102/103 comprising indium oxides, e.g. ITO
• CPC Class Codes: H10K 30/30 comprising bulk heterojunctions, e.g. interpenetrating networks of donor and acceptor material domains
• CPC Class Codes: H10K 30/82 Transparent electrodes, e.g. indium tin oxide [ITO] electrodes
• CPC Class Codes: H10K 71/12 using liquid deposition, e.g. spin coating
• CPC Class Codes: H10K 71/16 using physical vapour deposition [PVD], e.g. vacuum deposition or sputtering
• CPC Class Codes: H10K 71/40 Thermal treatment, e.g. annealing in the presence of a solvent vapour
• CPC Class Codes: H10K 85/30 Coordination compounds
• CPC Class Codes: H10K 85/50 Organic perovskites; Hybrid organic-inorganic perovskites [HOIP], e.g. CH3NH3PbI3
• CPC Class Codes: H10K 85/633 comprising polycyclic condensed aromatic hydrocarbons as substituents on the nitrogen atom
• CPC Class Codes: H10K 85/636 comprising heteroaromatic hydrocarbons as substituents on the nitrogen atom
• CPC Class Codes: Y02E 10/542 Dye sensitized solar cells
• CPC Class Codes: Y02E 10/549 : Organic PV cells

Abstract

A method for processing a perovskite photoactive layer. The method comprises depositing a lead salt precursor onto a substrate to form a lead salt thin film, depositing a second salt precursor onto the lead salt thin film, annealing the substrate to form a perovskite material.

Claims

1. A method for processing a perovskite photoactive layer comprising:

depositing a lead salt precursor onto a substrate to form a lead salt thin film;

depositing a second salt precursor onto the lead salt thin film; and

annealing the substrate to form a perovskite material.

2. The method of claim 1, wherein the lead salt precursor is deposited by spin-coating, slot-die printing, sputtering, PE-CVD, thermal evaporation, or spray coating.

3. The method of claim 1, wherein the second salt precursor is deposited by spin-coating, slot-die printing, sputtering, PE-CVD, thermal evaporation, or spray coating.

4. The method of claim 1, wherein the lead salt precursor comprises one or more lead salts selected from the group consisting of lead (II) iodide, lead (II) thiocyanate, lead (II) chloride, lead (II) bromide, and combinations thereof.

5. The method of claim 1, wherein the second salt comprises formamidinium iodide, formamidinium thiocyanate, or guanidinium thiocyanate.

6. The method of claim 1, wherein the lead salt precursor comprises a solution comprising one or more solvents selected from the group consisting of N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethylsulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof.

7. The method of claim 1, wherein the lead salt precursor contains one or more additives selected from the group consisting of an amino acid, 5-aminovaleric acid hydroiodide, 1,8-diiodooctane, 1,8-dithiooctane, formamidinium halide, acetic acid, trifluoroacetic acid, a methylammonium halide, water, and combinations thereof.

8. The method of claim 1, wherein the second salt precursor comprises a solution comprising one or more solvents selected from the group consisting of N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethylsulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof.

9. The method of claim 1, wherein annealing occurs in an atmosphere selected from the group consisting of ambient air, a controlled humidity environment, pure argon, pure nitrogen pure oxygen, pure hydrogen, pure helium, pure neon, pure krypton, pure CO₂, and combinations thereof.

10. The method of claim 1, wherein annealing occurs at a temperature greater than or equal to 50°

C. and less than or equal to 300°

C.

11. The method of claim 9, wherein annealing in a controlled humidity environment occurs at an absolute humidity greater than or equal to 0 g H₂O/m³ air and less than or equal to 20 g H₂O/m³ air

12. The method of claim 9, wherein annealing in a controlled humidity environment occurs at an absolute humidity between about 4 and 7 g H₂O/m³ air.

13. The method of claim 1, wherein the substrate has a temperature between 0°

C. and 500°

C.

14. The method of claim 1, further comprising drying the lead salt precursor in a substantially water-free atmosphere to form a lead salt thin film.

15. The method of claim 14, further comprising annealing the lead salt thin film at a temperature between about 20°

C. and about 300°

C.

16. The method of claim 1, wherein annealing the substrate occurs at about 125°

C.

17. A method for processing a perovskite photoactive layer comprising:

depositing a PbI₂ precursor onto a substrate to form a PbI₂ thin film, wherein the PbI₂ precursor comprises a 90;

10 mole ratio of PbI₂ to PbCl₂ dissolved in anhydrous DMF;

depositing a formamidinium iodide precursor onto the PbI₂ thin film, wherein the formamidinium iodide precursor comprises a 25-60 mg/mL concentration of formamidinium iodide dissolved in anhydrous isopropyl alcohol; and

annealing the substrate in a controlled humidity environment at a temperature greater than or equal to 50°

C. and less than or equal to 300°

C. to form a formamidinium lead iodide (FAPbI₃) perovskite material.

18. The method of claim 17, wherein the controlled humidity environment comprises an environment having between about 4 and 7 g H₂O/m³ air.

19. The method of claim 17, wherein annealing the substrate occurs at about 125°

C.

20. The method of claim 17, wherein the PbI₂ precursor further comprises one or more additives selected from the group consisting of 5-aminovaleric acid hydroiodide, 1,8-diiodooctane, 1,8-dithiooctane, formamidinium halide, acetic acid, trifluoroacetic acid, a methylammonium halide, water, and combinations thereof.

21. The method of claim 17, further comprising drying the PbI₂ precursor in a substantially water-free atmosphere for about one hour.

22. The method of claim 17, further comprising annealing the PbI₂ thin film for about ten minutes at a temperature of about 50°

C.

23. The method of claim 17, wherein the formamidinium iodide precursor is deposited at a temperature between about 25°

C. and about 125°

C.

24. The method of claim 17, wherein the substrate has a temperature between 0°

C. and 500°

C.

25. A photovoltaic device comprising:

a perovskite material comprising formamidinium lead iodide (FAPbI₃) having a cubic crystal structure.

26. The photovoltaic device of claim 25 wherein:

the FAPbI₃ has a cubic primitive crystal structure.

27. The photovoltaic device of claim 25 wherein:

the FAPbI₃ has a Pm-3m space group.

28. The photovoltaic device of claim 25 wherein:

the FAPbI₃ has an X-ray diffraction pattern having peaks, in terms of 2θ

, at 14.06±

0.1 and 24.30±

0.1 degrees.

29. The photovoltaic device of claim 25 wherein:

the FAPbI₃ has an X-ray diffraction pattern having peaks, in terms of 2θ

, at 14.06±

0.1, 19.84±

0.1, 24.30±

0.1, 28.15±

0.1, 31.55±

0.1, 34.63±

0.1, 40.30±

0.1, 42.78±

0.1, 45.48±

0.1, 49.77±

0.1, 51.79±

0.1, 58.13±

0.1, 58.70±

0.1, 62.02±

0.1, 65.75±

0.1, 67.43±

0.1, and 72.81±

0.1 degrees.

30. The photovoltaic device of claim 25 wherein:

the FAPbI₃ has a lattice parameter, a, equal to about 6.35 Å

.