Nanocomposite coatings for perovskite solar cells and methods of making the same

1. A method comprising:

in a first mixture comprising a metal alkoxide and water, reacting at least a portion of the metal alkoxide and at least a portion of the water to form a second mixture comprising a solid metal oxide phase;

applying the second mixture onto a surface of a device comprising an intervening layer adjacent to a photovoltaic perovskite layer such that the intervening layer is between the second mixture and the photovoltaic perovskite layer; and

treating the second mixture, such that the solid metal oxide phase is transformed to a first solid metal oxide layer such that the intervening layer is positioned between the first solid metal oxide layer and the photovoltaic perovskite layer, wherein:

the photovoltaic perovskite layer comprises an organic cation.

2. The method of claim 1 , wherein:

the metal alkoxide comprises Si(OR) 4 , and

the R group comprises at least one of an alkyl group or a polymeric group.

3. The method of claim 2 , wherein the polymeric group comprises at least one of a polystyrene group, a polyamide group, a poly(ethyleneimine) group, an epoxy group, a poly(ethylene oxide) group, a poly(oxypropylene) group, a poly(arylene ether phosphine oxide) group, a poly(arylene ether sulfone) group, a cellulose acetate group, a polyacrylic group, a polyacrylonitrile group, or a polybutadiene group.

4. The method of claim 2 , wherein the first solid metal oxide phase comprises a first network of interconnected silicon atoms comprising at least one of SiO 2 , SiO 1.5 OH, SiO(OH) 2 , SiO 0.5 (OH) 3 , SiO 1.5 R, SiOR 2 , SiO 0.5 R 3 , SiO 0.5 (OH)R 2 , SiO 0.5 (OH) 2 R, or SiO(OH)R and a first amount of unreacted Si(OR) 4 .

5. The method of claim 4 , wherein the first solid metal oxide layer comprises a second network of interconnected silicon atoms comprising at least one of SiO 2 , SiO 1.5 OH, SiO(OH) 2 , SiO 0.5 (OH) 3 , SiO 1.5 R, SiOR 2 , SiO 0.5 R 3 , SiO 0.5 (OH)R 2 , SiO 0.5 (OH) 2 R, or SiO(OH)R and a second amount of unreacted Si(OR) 4 that is less than the first amount.

6. The method of claim 1 , wherein the first mixture further comprises an alcohol.

7. The method of claim 5 , wherein:

the first mixture further comprises R′[Si(OR) 3 ] x where x is an integer value between 1 and 10 inclusively, and

the R′ group comprises an organic group.

8. The method of claim 7 , wherein the organic group comprises at least one of an alkane group, an alkene group, or an aromatic group.

9. The method of claim 7 , wherein the first network further comprises at least one of SiO 1.5 R′ 0.5 , SiOR′, SiO 0.5 R′ 1.5 , SiO(OH)R′ 0.5 , SiO 0.5 (OH)R′, or Si(OH)R′ 1.5 .

10. The method of claim 9 , wherein the second network further comprises at least one of SiO 1.5 R′ 0.5 , SiOR′, SiO 0.5 R′ 1.5 , SiO(OH)R′ 0.5 , SiO 0.5 (OH)R′, or Si(OH)R′ 1.5 .

11. The method of claim 1 , wherein the reacting is performed at a temperature between 25° C. and 95° C.

12. The method of claim 1 , wherein the applying is performed by at least one of dip coating, curtain coating, or spin coating.

13. The method of claim 1 , wherein the intervening layer comprises a second solid metal oxide layer.

14. The method of claim 13 , wherein the second solid metal oxide layer is substantially transparent to sunlight.

15. The method of claim 14 , wherein the second solid metal oxide layer comprises nickel oxide.

16. The method of claim 13 , wherein the second solid metal oxide layer has a thickness between 10 Å and 500 Å.

17. The method of claim 1 , wherein the perovskite comprises ABX 3 , where X comprises an anion, A comprises the organic cation, and B comprises a second cation.

18. The method of claim 13 , further comprising prior to the applying, depositing the second solid metal oxide layer onto the perovskite layer.

19. The method of claim 18 , wherein the depositing is performed by atomic layer deposition.

20. The method of claim 18 , further comprising prior to the depositing, forming the perovskite layer.

21. The method of claim 20 , wherein the forming is performed by at least one of a solution method or a vapor phase method.

22. The method of claim 1 , wherein the treating comprises at least one of heating the second mixture or exposing the second mixture to a gas.